Introducing my DIY amps.
Moderators: pompeiisneaks, Colossal
-
psychepool
- Posts: 286
- Joined: Fri Apr 18, 2014 8:29 am
5 others liked this
Introducing my DIY amps.
Hello everyone.
I have been making many amps as a hobby, and after throwing out the ones that I didn't like and trying out new circuits, I will introduce the amps that I have finally chosen and left behind.
In the beginning of DIYing amps, I made them however I was given the conditions, but at some point, I gained the ability to make them in the style I wanted, and all the amps I am introducing are the ones I made after that.
My build style is somewhat extreme. It is very small and dense. So as time passed and I got older while continuing this hobby, I felt that I no longer had the physical ability to build in this style.
So I thought that I should stop this hobby for a while, and so I thought that I would like to introduce the amps I have built to this place that helped me the most in continuing this hobby and express my gratitude.
The hobby of building guitar amplifiers is basically a hobby enjoyed by a small number of people, but it is even more so in the country where I live, so as a non-electrical major, I think I would never have been able to overcome the difficulties I encountered while building them without the help here.
I would like to express my deepest gratitude to you all.
The original circuits of the amplifiers are Bogner Ecstasy, SloRectoTwin, Diesel VH4, and Orange Rockerverb.
I named them Gold Lion, Cerberus, Kampfschwein, and Kodiac.
I will introduce them one by one in the thread below.
I couldn't find the appropriate board so I'm posting it here. If I posted it incorrectly, please let me know.
You do not have the required permissions to view the files attached to this post.
-
psychepool
- Posts: 286
- Joined: Fri Apr 18, 2014 8:29 am
4 others liked this
Re: Introducing my DIY amps.
==Dumble ODS==
Suddenly, I'm introducing the Dumble clone that wasn't mentioned above.
The reason I'm introducing the Dumble that wasn't mentioned above is because it's a monumental amp that was made with the same specifications and configuration by making this amp.
-Aluminum 1.5T chassis with a size of 310 x 160 x 60mm
-2 x 6L6GC power
-96 Core size PT
-Hammond 1760J OT
-4 x 12ax7
-Marshall 1987X TL072 FX Loop
That's why I'm introducing this amp before the other amps, even though I don't have it anymore.
The circuit is based on the #183 version.
There are still many things I don't know, but when I made this, it was about 12 years ago and I really didn't know anything, so I made it as close to the known circuit as possible.
One thing I added was a tube reverb. I found the following information on the web,
There was no mention of a verified circuit, but at the time, I had a fantasy about a built in spring reverb, so I tried it with an irresponsible thought that if it failed, I could just put an FX loop instead of a reverb.
I found out a long time after making it, but this was just a reference circuit, and there was no reason why it wouldn't work.
It was made like this.
It doesn't mean much, but I made a hole in the bottom of the cabinet and installed a reverb tank to make the cabinet a little smaller.
I made it when I was about 12 years younger, so I had a much healthier physique than I do now, and unlike now, and this hobby still felt new, and I also had a strong desire for a great build, so I think it was made with quite good quality.
However, even when I listened to the sound sample, I had a feeling that this amp would not be my taste, but since it was such a well-received amp and many people around me recommended it, I was pushed to build it, so when I listened to the sound after it was completed, it didn't have the sound I needed, and after using it for about 2 years, it ended up in someone else's possession.
What I was most worried about was the build stability, but in fact, I'm not a person who takes amps out of the house very often, so I couldn't verify how well the amp I made could withstand harsh environments.
However, I'm glad that I've heard from many people that someone is using it without any problems until recently.
Suddenly, I'm introducing the Dumble clone that wasn't mentioned above.
The reason I'm introducing the Dumble that wasn't mentioned above is because it's a monumental amp that was made with the same specifications and configuration by making this amp.
-Aluminum 1.5T chassis with a size of 310 x 160 x 60mm
-2 x 6L6GC power
-96 Core size PT
-Hammond 1760J OT
-4 x 12ax7
-Marshall 1987X TL072 FX Loop
That's why I'm introducing this amp before the other amps, even though I don't have it anymore.
The circuit is based on the #183 version.
There are still many things I don't know, but when I made this, it was about 12 years ago and I really didn't know anything, so I made it as close to the known circuit as possible.
One thing I added was a tube reverb. I found the following information on the web,
There was no mention of a verified circuit, but at the time, I had a fantasy about a built in spring reverb, so I tried it with an irresponsible thought that if it failed, I could just put an FX loop instead of a reverb.
I found out a long time after making it, but this was just a reference circuit, and there was no reason why it wouldn't work.
It was made like this.
It doesn't mean much, but I made a hole in the bottom of the cabinet and installed a reverb tank to make the cabinet a little smaller.
I made it when I was about 12 years younger, so I had a much healthier physique than I do now, and unlike now, and this hobby still felt new, and I also had a strong desire for a great build, so I think it was made with quite good quality.
However, even when I listened to the sound sample, I had a feeling that this amp would not be my taste, but since it was such a well-received amp and many people around me recommended it, I was pushed to build it, so when I listened to the sound after it was completed, it didn't have the sound I needed, and after using it for about 2 years, it ended up in someone else's possession.
What I was most worried about was the build stability, but in fact, I'm not a person who takes amps out of the house very often, so I couldn't verify how well the amp I made could withstand harsh environments.
However, I'm glad that I've heard from many people that someone is using it without any problems until recently.
You do not have the required permissions to view the files attached to this post.
-
sluckey
- Posts: 3398
- Joined: Sun Jul 22, 2007 7:48 pm
- Location: Mobile, AL
- Contact:
1 others liked this
Re: Introducing my DIY amps.
I like knobs! 
-
psychepool
- Posts: 286
- Joined: Fri Apr 18, 2014 8:29 am
3 others liked this
Re: Introducing my DIY amps.
==Gold Lion (Based on Bogner Ecstasy)==
From now on, I will introduce the amplifiers that I have.
First, Bogner Ecstasy.
I named it Gold Lion for simple reasons such as the British style circuit, the signature gold panel, etc. Naming is always difficult.
Based on Bogner Ecstasy.
Original amp has 3-channel with Green(Clean)/Blue(Crunch)/Red(Lead),
but in order to fit it in a small space, the functions had to be shortened.
Later, I ended up making 3-channel and 4-channel amplifiers...but at that time, I didn't think that would be possible.
So I decided to configure the footswitchable channel with only 2 channels, Clean/Dirty, and configure Plexi/Blue/Red as 'modes' rather than 'channels' within the dirty channel.
The reason I chose this circuit was because it was closer to the original Marshall circuit than other Marshall hot rods.
I thought that if it was closer to the original circuit, it would be possible to modify it to access a wider variety of Marshall sounds.
So, after completing it, I made several additional modifications, and the final circuit is like this.
In order to reduce the number of tubes, the FX loop uses the solid state loop from the Marshall 1987X reissue instead of the tube loop.
And the clean channel is not a completely independent structure, but is made to share the 1st stage with the dirty channel.
There are many mods applied to the dirty channel.
First, the structure mode has been changed from the existing 2 stages to 4 stages.
-JCM800 / Bogner Low / Vintage hot mod / Bogner HI-
Actually, the original intention was to add only the JCM800 mode to the existing Lo/Hi mode, but I needed a mini 4Pole switch, and since I only had a 4P4T mini 4Pole switch, I made it a 4 modes.
The part marked in blue is the structure switching configuration.
The JCM800 mode is not a perfect configuration and is only a configuration that feel the taste of, but it was a very satisfying option.
The Ecstasy sound feels very cleanly polished overall, but the JCM800 mode has a messy, drunken sound that I like.
The 'Vintage hot mod' that I added unintentionally has a cathode value of 4.7K/100n and also has the treble peak cap of the JCM800 mod.
It is a very sharp sound with ear-piercing treble. It feels like old 70's British rock, but the sound is somewhat unbalanced, so I thought about adjusting it a little, but since all the modes I wanted were applied anyway, and since it was an additional mode, I thought it would be nice to have a very extreme sound, so I left it as is.
The gain pot bright switch called Pre EQ was changed from the existing 470pF/None/4.7n to 100pF/1n/4.7n.
The reason I put in 100pF is because I wanted to implement the voicing of JTM45 in Plexi mode, and I am satisfied because it produces a much more elastic sound than None mode.
If put it in 100pF in Plexi mode, break it up slightly, and then put a bluesbreaker pedal, I can get a fantastic sound.
The reason I put in 1n instead of 470pF was to produce the JCM800 sound, but I am not very satisfied with the frequency. It feels like only the bands I don't like are popping out, but it definitely has a classic Marshall-like nuance better than 470pF or 4.7n, so I don't regret choosing it.
The red channel mode called Marvel mode was applied as the known value.
When I first applied it, the sound became very hot and I was satisfied,
but as I continued to use it, I was uncomfortable with the fact that the noise increased a lot, so I thought about just removing it.
However, as I used it more, I thought it was useful as a role to supplement the distortion that was lacking in low structure or pre-EQ settings, so I ended up applying it.
I applied a mode that switches the coupling caps of the 1st and 2nd stages. The original circuit is 4.7n/2.2n respectively, but it can be used in 4.7n/22n mode and 22n/22n mode through switching.
The original purpose was to provide sufficient growling in JCM800 mode and flexi mode, but after using it, I ended up always using 22n/22n in all modes. I really like it.
In other circuits, the coupling cap of 22n would have felt quite messy,
but thanks to Marshall's unique low-cut circuit configuration, the high-gain low sound in 22n mode does not feel loose and fluffy, but rather feels very fierce, which is nice.
There is a mode written as Comp A/B.
A is diode clipping (aka. Jose Mod) and B is the same as the Voice switch in the Friedman BE-100.
The diode combination is 20V Zener and MPSA06.
The original Jose Mod has the master volume in front of the EQ, and the capacitor and resistor are located in series between the cathode follower and the master volume, but I think the default is the state without the clipper, so I made it with the same structure as the Friedman BE-100 so that the circuit is not affected when turned off.
The voice switch is a combination of 1n-none-2.2n. 1n sounds okay, but 2.2n seems to cut the tone a bit much. I plan to consider other options through testing for 2.2n in the future.
I added functions to the power amplifier section with reference to the Friedman BE-50 Deluxe circuit.
It's almost copied as a reference.
NFB, Depth, Presence.
I really like the role of the NFB knob.
If reduce the knob, you get a very modern and neat sound, and the influence of depth and presence increases. On the other hand, when turn up the knob, the depth and presence become dull, but it becomes a vintage sound that cuts through quite wildly.
I really like this knob because it completely changes the overall character of the amp.
For the FX loop, I used the TL072 loop of Marshall 1987X, which is common with other amps I've made.
The power supply is also simple and the transparency is high, so I'm very satisfied.
The footswitches are a clean/dirty switch and a boost switch.
In fact, from a circuit perspective, the boost is not a boost, but an unboost concept.
So I usually keep it turned on and don't use it much.
Since there are many functions, the explanation is also quite long.
The overall internal build photos are like this.
I was worried whether this size of circuit could be made in this chassis, but I attached it step by step and it was made without any major problems.
I was worried that it would break down or malfunction if it was this small, but it has been about 8 years since I made it and used it, but it has not broken down yet.
I used it continuously for more than two to three hours, but the amp did not feel particularly unstable. Of course, it has a lot of heat due to the small chassis size.
Of the amps introduced, this one was made the longest, but I modified it the most and like it the most.
For me, the reference tone for guitar amps is definitely Marshall.
From now on, I will introduce the amplifiers that I have.
First, Bogner Ecstasy.
I named it Gold Lion for simple reasons such as the British style circuit, the signature gold panel, etc. Naming is always difficult.
Based on Bogner Ecstasy.
Original amp has 3-channel with Green(Clean)/Blue(Crunch)/Red(Lead),
but in order to fit it in a small space, the functions had to be shortened.
Later, I ended up making 3-channel and 4-channel amplifiers...but at that time, I didn't think that would be possible.
So I decided to configure the footswitchable channel with only 2 channels, Clean/Dirty, and configure Plexi/Blue/Red as 'modes' rather than 'channels' within the dirty channel.
The reason I chose this circuit was because it was closer to the original Marshall circuit than other Marshall hot rods.
I thought that if it was closer to the original circuit, it would be possible to modify it to access a wider variety of Marshall sounds.
So, after completing it, I made several additional modifications, and the final circuit is like this.
In order to reduce the number of tubes, the FX loop uses the solid state loop from the Marshall 1987X reissue instead of the tube loop.
And the clean channel is not a completely independent structure, but is made to share the 1st stage with the dirty channel.
There are many mods applied to the dirty channel.
First, the structure mode has been changed from the existing 2 stages to 4 stages.
-JCM800 / Bogner Low / Vintage hot mod / Bogner HI-
Actually, the original intention was to add only the JCM800 mode to the existing Lo/Hi mode, but I needed a mini 4Pole switch, and since I only had a 4P4T mini 4Pole switch, I made it a 4 modes.
The part marked in blue is the structure switching configuration.
The JCM800 mode is not a perfect configuration and is only a configuration that feel the taste of, but it was a very satisfying option.
The Ecstasy sound feels very cleanly polished overall, but the JCM800 mode has a messy, drunken sound that I like.
The 'Vintage hot mod' that I added unintentionally has a cathode value of 4.7K/100n and also has the treble peak cap of the JCM800 mod.
It is a very sharp sound with ear-piercing treble. It feels like old 70's British rock, but the sound is somewhat unbalanced, so I thought about adjusting it a little, but since all the modes I wanted were applied anyway, and since it was an additional mode, I thought it would be nice to have a very extreme sound, so I left it as is.
The gain pot bright switch called Pre EQ was changed from the existing 470pF/None/4.7n to 100pF/1n/4.7n.
The reason I put in 100pF is because I wanted to implement the voicing of JTM45 in Plexi mode, and I am satisfied because it produces a much more elastic sound than None mode.
If put it in 100pF in Plexi mode, break it up slightly, and then put a bluesbreaker pedal, I can get a fantastic sound.
The reason I put in 1n instead of 470pF was to produce the JCM800 sound, but I am not very satisfied with the frequency. It feels like only the bands I don't like are popping out, but it definitely has a classic Marshall-like nuance better than 470pF or 4.7n, so I don't regret choosing it.
The red channel mode called Marvel mode was applied as the known value.
When I first applied it, the sound became very hot and I was satisfied,
but as I continued to use it, I was uncomfortable with the fact that the noise increased a lot, so I thought about just removing it.
However, as I used it more, I thought it was useful as a role to supplement the distortion that was lacking in low structure or pre-EQ settings, so I ended up applying it.
I applied a mode that switches the coupling caps of the 1st and 2nd stages. The original circuit is 4.7n/2.2n respectively, but it can be used in 4.7n/22n mode and 22n/22n mode through switching.
The original purpose was to provide sufficient growling in JCM800 mode and flexi mode, but after using it, I ended up always using 22n/22n in all modes. I really like it.
In other circuits, the coupling cap of 22n would have felt quite messy,
but thanks to Marshall's unique low-cut circuit configuration, the high-gain low sound in 22n mode does not feel loose and fluffy, but rather feels very fierce, which is nice.
There is a mode written as Comp A/B.
A is diode clipping (aka. Jose Mod) and B is the same as the Voice switch in the Friedman BE-100.
The diode combination is 20V Zener and MPSA06.
The original Jose Mod has the master volume in front of the EQ, and the capacitor and resistor are located in series between the cathode follower and the master volume, but I think the default is the state without the clipper, so I made it with the same structure as the Friedman BE-100 so that the circuit is not affected when turned off.
The voice switch is a combination of 1n-none-2.2n. 1n sounds okay, but 2.2n seems to cut the tone a bit much. I plan to consider other options through testing for 2.2n in the future.
I added functions to the power amplifier section with reference to the Friedman BE-50 Deluxe circuit.
It's almost copied as a reference.
NFB, Depth, Presence.
I really like the role of the NFB knob.
If reduce the knob, you get a very modern and neat sound, and the influence of depth and presence increases. On the other hand, when turn up the knob, the depth and presence become dull, but it becomes a vintage sound that cuts through quite wildly.
I really like this knob because it completely changes the overall character of the amp.
For the FX loop, I used the TL072 loop of Marshall 1987X, which is common with other amps I've made.
The power supply is also simple and the transparency is high, so I'm very satisfied.
The footswitches are a clean/dirty switch and a boost switch.
In fact, from a circuit perspective, the boost is not a boost, but an unboost concept.
So I usually keep it turned on and don't use it much.
Since there are many functions, the explanation is also quite long.
The overall internal build photos are like this.
I was worried whether this size of circuit could be made in this chassis, but I attached it step by step and it was made without any major problems.
I was worried that it would break down or malfunction if it was this small, but it has been about 8 years since I made it and used it, but it has not broken down yet.
I used it continuously for more than two to three hours, but the amp did not feel particularly unstable. Of course, it has a lot of heat due to the small chassis size.
Of the amps introduced, this one was made the longest, but I modified it the most and like it the most.
For me, the reference tone for guitar amps is definitely Marshall.
You do not have the required permissions to view the files attached to this post.
-
psychepool
- Posts: 286
- Joined: Fri Apr 18, 2014 8:29 am
2 others liked this
Re: Introducing my DIY amps.
==Cerberus(SloRectoTwin)==
This is the amp I built after Ecstasy.
Ecstasy had enough gain range, but Marshall's tone character was definitely not suitable for Modern Chug, so I chose it because I thought it would be nice to have an amp based on Mesa Boogie Rectifier.
Naming is always difficult. This time, I named it Cerberus simply because it was a 3-channel amp. Later, I made a 4-channel amp, but up until then, a 3-channel amp was a big challenge for me.
It was originally a preamp circuit, but since I do not plan to use a preamp, I approached it with the idea of building a full-amp from the beginning.
While building this amp, I found out that Mesa Recto is a copy of Soldano SLO. Of course, there are many original elements, but the signal part of the channel itself was almost the same.
And the circuit diagram of SloRectoTwin circulating on the web is closer to SLO circuit than Recto circuit, so some modifications were needed.
The circuit I found on the web is as follows.
The final fixed circuit diagram after make is like this.
It is a 3-channel circuit, but it feels simpler than Bogner.
There were two problems when I made it according to the circuit diagram I found on the web.
-The lead channel is not Recto sound.
-The sound of the crunch channel is too weak and unattractive.
The reason why Recto sound did not come out of the lead channel is simple.
It is because it is a Soldano circuit, not a Recto circuit.
There are some minor differences between Recto and Soldano, but the decisive difference is the presence (tone cut) circuit located between the tone stack and the master volume. This cuts the high end beautifully and creates a uniquely wonderful low-mid sound, but this is omitted in the SloRectoTwin circuits.
Apply as follows.
And the vintage/modern switch, which can be said to be the core function of the Recto, is also omitted.
This is the function of shorting the NFB in the power amplifier, and since SloRectoTwin is a preamp circuit, it is naturally omitted.
The modern mode is well suited to high-gain sounds for metal, and the vintage mode has a thick and rich feel, so it is quite bluesy and pop.
If the presence circuit is added, it becomes the Recto sound, but conversely, if this is removed, it becomes the SLO sound.
I removed the presence circuit, connected the NFB, and set the global presence of the power amplifier to a fixed value so that the SLO lead channel can also be used.
This is roughly the configuration.
The problem with the crunch channel is that the overall gain is too weak, resulting in a weak sound.
In fact, to implement the Soldano Crunch Channel, it would be standard to bypass all 2nd and 3rd stages like SLO and add a separate stage for the crunch channel, but there was no space to install an additional tube in the chassis. Instead, this circuit is configured to bypass the 2nd stage.
As a result, the 2-stage cathode resistance value is too high at 39K, so to compensate for this, additional resistance and caps are added in parallel to the existing cathode resistance at the same time as the channel switching.
I added about 15K/1uF, and it feels appropriate. It gives me the thick and creamy sound of the SLO that I knew.
And since there is a vintage/modern switch in the lead channel, I will also make a vintage modern switch in the crunch channel.
Each channel has a high-value coupling cap of 47n in common, and a 2.2n cap is additionally attached in series in front of the crunch channel to tighten the low-frequency range, and the gain that is reduced as the low-frequency range is cut is compensated by adding a cathode bypass cap.
It is not a very dramatic difference, but I feel that it is a very useful mod.
However, since the cathode resistance value is switched when switching channels like this, there' loud pop noise is when switching between crunch/lead.
It would be good to remove it, but since I connect an attenuator when using it at home, it is not particularly inconvenient, so I leave it alone for now.
The clean channel is a Blackface circuit. That is why I like the clean channel the most among the amplifiers I have made. There was nothing special to do. I added a 100pF/220pF bright switch, but I use it in off mode most of the time.
As expected, the FX loop is the opamp FX Loop of the 1987X.
The channel switching is done by switching between three channels via two footswitches.
One footswitch switches between clean/dirty, and the other switches between crunch/lead.
I don't know if it means much, but since Mesa Recto uses orange drop and carbon film, I made it that way too.
This is the amp I built after Ecstasy.
Ecstasy had enough gain range, but Marshall's tone character was definitely not suitable for Modern Chug, so I chose it because I thought it would be nice to have an amp based on Mesa Boogie Rectifier.
Naming is always difficult. This time, I named it Cerberus simply because it was a 3-channel amp. Later, I made a 4-channel amp, but up until then, a 3-channel amp was a big challenge for me.
It was originally a preamp circuit, but since I do not plan to use a preamp, I approached it with the idea of building a full-amp from the beginning.
While building this amp, I found out that Mesa Recto is a copy of Soldano SLO. Of course, there are many original elements, but the signal part of the channel itself was almost the same.
And the circuit diagram of SloRectoTwin circulating on the web is closer to SLO circuit than Recto circuit, so some modifications were needed.
The circuit I found on the web is as follows.
The final fixed circuit diagram after make is like this.
It is a 3-channel circuit, but it feels simpler than Bogner.
There were two problems when I made it according to the circuit diagram I found on the web.
-The lead channel is not Recto sound.
-The sound of the crunch channel is too weak and unattractive.
The reason why Recto sound did not come out of the lead channel is simple.
It is because it is a Soldano circuit, not a Recto circuit.
There are some minor differences between Recto and Soldano, but the decisive difference is the presence (tone cut) circuit located between the tone stack and the master volume. This cuts the high end beautifully and creates a uniquely wonderful low-mid sound, but this is omitted in the SloRectoTwin circuits.
Apply as follows.
And the vintage/modern switch, which can be said to be the core function of the Recto, is also omitted.
This is the function of shorting the NFB in the power amplifier, and since SloRectoTwin is a preamp circuit, it is naturally omitted.
The modern mode is well suited to high-gain sounds for metal, and the vintage mode has a thick and rich feel, so it is quite bluesy and pop.
If the presence circuit is added, it becomes the Recto sound, but conversely, if this is removed, it becomes the SLO sound.
I removed the presence circuit, connected the NFB, and set the global presence of the power amplifier to a fixed value so that the SLO lead channel can also be used.
This is roughly the configuration.
The problem with the crunch channel is that the overall gain is too weak, resulting in a weak sound.
In fact, to implement the Soldano Crunch Channel, it would be standard to bypass all 2nd and 3rd stages like SLO and add a separate stage for the crunch channel, but there was no space to install an additional tube in the chassis. Instead, this circuit is configured to bypass the 2nd stage.
As a result, the 2-stage cathode resistance value is too high at 39K, so to compensate for this, additional resistance and caps are added in parallel to the existing cathode resistance at the same time as the channel switching.
I added about 15K/1uF, and it feels appropriate. It gives me the thick and creamy sound of the SLO that I knew.
And since there is a vintage/modern switch in the lead channel, I will also make a vintage modern switch in the crunch channel.
Each channel has a high-value coupling cap of 47n in common, and a 2.2n cap is additionally attached in series in front of the crunch channel to tighten the low-frequency range, and the gain that is reduced as the low-frequency range is cut is compensated by adding a cathode bypass cap.
It is not a very dramatic difference, but I feel that it is a very useful mod.
However, since the cathode resistance value is switched when switching channels like this, there' loud pop noise is when switching between crunch/lead.
It would be good to remove it, but since I connect an attenuator when using it at home, it is not particularly inconvenient, so I leave it alone for now.
The clean channel is a Blackface circuit. That is why I like the clean channel the most among the amplifiers I have made. There was nothing special to do. I added a 100pF/220pF bright switch, but I use it in off mode most of the time.
As expected, the FX loop is the opamp FX Loop of the 1987X.
The channel switching is done by switching between three channels via two footswitches.
One footswitch switches between clean/dirty, and the other switches between crunch/lead.
I don't know if it means much, but since Mesa Recto uses orange drop and carbon film, I made it that way too.
You do not have the required permissions to view the files attached to this post.
-
psychepool
- Posts: 286
- Joined: Fri Apr 18, 2014 8:29 am
2 others liked this
Re: Introducing my DIY amps.
==Kampfschwein(Deizel VH4)==
I finally got to build a 4-channel amplifier.
I have never owned a Diezel VH4, and I have never actually seen one. So I thought it was a fantasy dragon or unicorn, but I became very interested in it after Tool's long-awaited new album came out a few years ago.
While searching the web to find some information, I was able to obtain a fairly detailed circuit diagram from a forum where discussions on high-gain amplifiers were active, and although it wasn't an amplifier I really wanted to build, I couldn't resist my curiosity and decided to build it.
The original amplifier used two tubes in the FX loop and even a MIDI switcher circuit, so it was quite complex, fancy, and expensive, but I changed the FX loop to a solid state and changed the switcher to a simple circuit that only allows channel switching, so the burden was greatly reduced.
Although it is a 4-channel amplifier, but if take these things out, it becomes a simple amplifier that is not particularly more complicated than the amplifiers I've previously built.
There is nothing to modify in this amp from the existing circuit.
The circuit itself is highly complete, but more than anything, since there are 4 channels, there is no need to make any special efforts to create additional tone characters.
I built it straight without any hesitation.
In fact, other circuits have traces of modifying old legendary circuits, but this amp doesn't feel like it was modified based on a specific amp, so it was even harder to get the motivation to modify it additionally.
The overall sound is very similar for channels 3 and 4, but the other channels show quite different characters.
Channel 2 has a fairly Marshall-like sound, and when the bright cap is on, I can feel a very pleasant sparkle sound.
Channel 3 requires boost to make useful tight high gain, but channel 4 produces a very tight sound and long sustain even without boost.
However, channel 4 feels too full and there is a lot of compression, so channel 3 feels a bit more wild and dynamic.
The regrettable point is that the headroom of the clean channel is somewhat lacking. I think it is a problem that arises when making a 100W amplifier into 35~40W.
It is not that I can't use a clean sound, but I have to always set the master volume to the maximum and use the gain knob as a volume.
And the overall channel feels overly organized, which is an advantage, but it also feels a bit tiring.
This is the circuit I made.
The resistors and capacitors are connected to the cathode follower out to make a filter, and I guess this part creates the unique overly refined feeling.
This is the inside,
As also it doesn't mean much, but since the original amp used Wima MKP10 cap and carbon film resistors, I just copied it without much thought.
I've never made the same circuit using various caps, so I can't say anything about the sound of Wima MKP10, but at least in terms of build, the small size of the Wima cap helped me a lot with my extreme build.
Other amps I've made only needed two footswitches, so I made them in a 1590A case, but this amp needs four footswitches anyway, so I made them in a slightly larger case. Actually, I wanted to make it a little smaller than this, but there was no suitable size among the Hammond die-cast cases.
The reason I was initially interested in this amp was because of the sound of Tool,
so I wanted to name the amp something surreal and majestic or like a natural disaster, but when I finished it and listened to the sound, it felt like a very aggressive pig, so since it is also a German brand circuit, I named it Kampfschwein.
Since the original amp had an impressive white Tolex design, I also worked with white Tolex.
It was definitely more burdensome to work with than black Tolex, but fortunately, it doesn't seem to have any parts that were finished too unsightly.
I finally got to build a 4-channel amplifier.
I have never owned a Diezel VH4, and I have never actually seen one. So I thought it was a fantasy dragon or unicorn, but I became very interested in it after Tool's long-awaited new album came out a few years ago.
While searching the web to find some information, I was able to obtain a fairly detailed circuit diagram from a forum where discussions on high-gain amplifiers were active, and although it wasn't an amplifier I really wanted to build, I couldn't resist my curiosity and decided to build it.
The original amplifier used two tubes in the FX loop and even a MIDI switcher circuit, so it was quite complex, fancy, and expensive, but I changed the FX loop to a solid state and changed the switcher to a simple circuit that only allows channel switching, so the burden was greatly reduced.
Although it is a 4-channel amplifier, but if take these things out, it becomes a simple amplifier that is not particularly more complicated than the amplifiers I've previously built.
There is nothing to modify in this amp from the existing circuit.
The circuit itself is highly complete, but more than anything, since there are 4 channels, there is no need to make any special efforts to create additional tone characters.
I built it straight without any hesitation.
In fact, other circuits have traces of modifying old legendary circuits, but this amp doesn't feel like it was modified based on a specific amp, so it was even harder to get the motivation to modify it additionally.
The overall sound is very similar for channels 3 and 4, but the other channels show quite different characters.
Channel 2 has a fairly Marshall-like sound, and when the bright cap is on, I can feel a very pleasant sparkle sound.
Channel 3 requires boost to make useful tight high gain, but channel 4 produces a very tight sound and long sustain even without boost.
However, channel 4 feels too full and there is a lot of compression, so channel 3 feels a bit more wild and dynamic.
The regrettable point is that the headroom of the clean channel is somewhat lacking. I think it is a problem that arises when making a 100W amplifier into 35~40W.
It is not that I can't use a clean sound, but I have to always set the master volume to the maximum and use the gain knob as a volume.
And the overall channel feels overly organized, which is an advantage, but it also feels a bit tiring.
This is the circuit I made.
The resistors and capacitors are connected to the cathode follower out to make a filter, and I guess this part creates the unique overly refined feeling.
This is the inside,
As also it doesn't mean much, but since the original amp used Wima MKP10 cap and carbon film resistors, I just copied it without much thought.
I've never made the same circuit using various caps, so I can't say anything about the sound of Wima MKP10, but at least in terms of build, the small size of the Wima cap helped me a lot with my extreme build.
Other amps I've made only needed two footswitches, so I made them in a 1590A case, but this amp needs four footswitches anyway, so I made them in a slightly larger case. Actually, I wanted to make it a little smaller than this, but there was no suitable size among the Hammond die-cast cases.
The reason I was initially interested in this amp was because of the sound of Tool,
so I wanted to name the amp something surreal and majestic or like a natural disaster, but when I finished it and listened to the sound, it felt like a very aggressive pig, so since it is also a German brand circuit, I named it Kampfschwein.
Since the original amp had an impressive white Tolex design, I also worked with white Tolex.
It was definitely more burdensome to work with than black Tolex, but fortunately, it doesn't seem to have any parts that were finished too unsightly.
You do not have the required permissions to view the files attached to this post.
-
psychepool
- Posts: 286
- Joined: Fri Apr 18, 2014 8:29 am
2 others liked this
Re: Introducing my DIY amps.
==Kodiac(Orange Rockerverb)==
This is my last amp that I made recently.
Actually, this is what I originally planned to make when I made the VH4.
As I said above therad, the VH4 was made somewhat impulsively, and after my curiosity was satisfied, I finally made what I originally wanted.
I can find a fairly detailed circuit for the Rockerverb on the web, but since I'm doing DIY anyway, I thought it would be a waste to make it as is, so I made it with 3 channels.
It was inspired by Dual Dark.
Although the known circuit diagram for Dual Dark is not available, but anyone interested in Orange amps will notice that it consists of Rockerverb channel and TH30 channel.
Even if that's not thue, it feels reasonable to make it that way.
So I decided to make it with 3 channels: Clean channel/Rockerverb channel/TH30 channel.
The problem is that the size of the amp I'm making is quite small. I tried to minimize the number of tubes.
As a result, I configured the circuit as follows.
The two dirty channels were configured to share the 1st/4nd stage.
In fact, since the only difference between the two dirty channels is the tone stack, it would be possible to configure the channel by switching only the gain pot and tone stack, but since the gain pot is directly connected to the grid, switching like this would generate significant popping noise, and I would also like to apply additional modifiers to each channel, but that would be impossible if I made it by sharing all the stages, so I chose this configuration.
I made a clean channel with one 12AX7 saved from the dirty channel.
Anyway, the number of 12AX7s is now 5, so it is one more than the amplifiers I have made so far, so it was difficult to make it with the layout of the existing amplifiers, so I made it with the power tube placed at the back of the chassis and the preamp tube placed at the front of the chassis.
This configuration made it difficult to build it with a turret board like before.
If put in a turret board, there would be no space to place other outboards such as relays or FX loops.
That's why I built it with hardwiring.
The biggest complaint I had when building it with a turret board was that I had to complete the entire board to check its operation.
This was because the debugging range was wide, so I always had to go through a difficult debugging process.
But if I built it with hardwiring, I could build it partially, so I could build it one by one from the back stage and have a narrow debugging range.
Of course, it's not easy to connect the parts in a three-dimensional and dense manner, so turret boards and hardwiring each have their own pros and cons.
One thing that's clear is that all the amplifiers I've built are amplifiers that can be set to high gain, and neither turret boards nor hardwiring are suitable for building high-gain amplifiers.
I built the clean channel with no mods. It was a sound with a nuance similar to Vox Top Boost with a reduced EQ range.
I didn't like it that much, so I thought about changing it to a Fender Blackface circuit, but I left it for now because I thought it had its own unique character.
I did a simple modification on each dirty channel.
I added one toggle for the low-frequency setting and one for the high-frequency setting to the Rockerverb channel.
I named them Growl and Bite respectively.
Bite mode is a Bright switch.
Orange has a unique solid mid-range tone that is attractive, but I thought it would be nice to add a little more sparkle.
So I added a Bright cap to pins 2 and 3 of the second gain pot.
I added a three-stage mode of none-100pF-470pF through the on-on-on switch.
100pF is satisfying because it adds a nice sparkle at low gain settings. It adds life to clean/crunch settings.
470pF creates a typical Marshall recipe 470K/470pF filter at the 12 o'clock gain pot setting.
It's so Marshall-like that it feels like modified an Orange tone on a Marshall amp, not an Marshall tone on an Orange amp.
It feels like the tone variation has widened considerably with a simple mod.
Growl mode is a coupling cap switch.
If you compare the circuits of Jim Root Terror and Rocker Cover, the coupling cap after the 2nd stage is 2.2n for Rocker Cover and 4.7n for Jim Root Terror.
So I applied the 1st through parallel connection of 2.2n caps, and additionally applied the 2nd by parallel connection of 1n to the 1st stage 1n coupling cap.
In fact, what I wanted in this mode was a loose and messy sound like doom metal, but it wasn't easy to produce that kind of tone. This mod gives very subtle change. I feel like I need to fix some other parts together and I had an idea that I wanted to try, but it was too much trouble, so I just finished it.
I added Dark Terror mode to the TH30 channel. (named "Claw")
There is only one difference between the TH30 preamp and the Dark Terror preamp, which is that there is a 4.7K high-pass resistor on the treble side of the tone stack.
When this is connected, the ultra-high range comes alive and a considerably Thrashy Metal feeling comes alive.
It is not the type of sound that I really like, but I thought it would be useful, so I added it through the switch.
The Rockerverb is famous for its unique high-gain tone, but I mainly use the raw and thick feeling with a lot of mid in the medium/low gain.
I feels It is much closer to the British sound than the Marshall-based circuit, like Ecstasy.
This is my last amp that I made recently.
Actually, this is what I originally planned to make when I made the VH4.
As I said above therad, the VH4 was made somewhat impulsively, and after my curiosity was satisfied, I finally made what I originally wanted.
I can find a fairly detailed circuit for the Rockerverb on the web, but since I'm doing DIY anyway, I thought it would be a waste to make it as is, so I made it with 3 channels.
It was inspired by Dual Dark.
Although the known circuit diagram for Dual Dark is not available, but anyone interested in Orange amps will notice that it consists of Rockerverb channel and TH30 channel.
Even if that's not thue, it feels reasonable to make it that way.
So I decided to make it with 3 channels: Clean channel/Rockerverb channel/TH30 channel.
The problem is that the size of the amp I'm making is quite small. I tried to minimize the number of tubes.
As a result, I configured the circuit as follows.
The two dirty channels were configured to share the 1st/4nd stage.
In fact, since the only difference between the two dirty channels is the tone stack, it would be possible to configure the channel by switching only the gain pot and tone stack, but since the gain pot is directly connected to the grid, switching like this would generate significant popping noise, and I would also like to apply additional modifiers to each channel, but that would be impossible if I made it by sharing all the stages, so I chose this configuration.
I made a clean channel with one 12AX7 saved from the dirty channel.
Anyway, the number of 12AX7s is now 5, so it is one more than the amplifiers I have made so far, so it was difficult to make it with the layout of the existing amplifiers, so I made it with the power tube placed at the back of the chassis and the preamp tube placed at the front of the chassis.
This configuration made it difficult to build it with a turret board like before.
If put in a turret board, there would be no space to place other outboards such as relays or FX loops.
That's why I built it with hardwiring.
The biggest complaint I had when building it with a turret board was that I had to complete the entire board to check its operation.
This was because the debugging range was wide, so I always had to go through a difficult debugging process.
But if I built it with hardwiring, I could build it partially, so I could build it one by one from the back stage and have a narrow debugging range.
Of course, it's not easy to connect the parts in a three-dimensional and dense manner, so turret boards and hardwiring each have their own pros and cons.
One thing that's clear is that all the amplifiers I've built are amplifiers that can be set to high gain, and neither turret boards nor hardwiring are suitable for building high-gain amplifiers.
I built the clean channel with no mods. It was a sound with a nuance similar to Vox Top Boost with a reduced EQ range.
I didn't like it that much, so I thought about changing it to a Fender Blackface circuit, but I left it for now because I thought it had its own unique character.
I did a simple modification on each dirty channel.
I added one toggle for the low-frequency setting and one for the high-frequency setting to the Rockerverb channel.
I named them Growl and Bite respectively.
Bite mode is a Bright switch.
Orange has a unique solid mid-range tone that is attractive, but I thought it would be nice to add a little more sparkle.
So I added a Bright cap to pins 2 and 3 of the second gain pot.
I added a three-stage mode of none-100pF-470pF through the on-on-on switch.
100pF is satisfying because it adds a nice sparkle at low gain settings. It adds life to clean/crunch settings.
470pF creates a typical Marshall recipe 470K/470pF filter at the 12 o'clock gain pot setting.
It's so Marshall-like that it feels like modified an Orange tone on a Marshall amp, not an Marshall tone on an Orange amp.
It feels like the tone variation has widened considerably with a simple mod.
Growl mode is a coupling cap switch.
If you compare the circuits of Jim Root Terror and Rocker Cover, the coupling cap after the 2nd stage is 2.2n for Rocker Cover and 4.7n for Jim Root Terror.
So I applied the 1st through parallel connection of 2.2n caps, and additionally applied the 2nd by parallel connection of 1n to the 1st stage 1n coupling cap.
In fact, what I wanted in this mode was a loose and messy sound like doom metal, but it wasn't easy to produce that kind of tone. This mod gives very subtle change. I feel like I need to fix some other parts together and I had an idea that I wanted to try, but it was too much trouble, so I just finished it.
I added Dark Terror mode to the TH30 channel. (named "Claw")
There is only one difference between the TH30 preamp and the Dark Terror preamp, which is that there is a 4.7K high-pass resistor on the treble side of the tone stack.
When this is connected, the ultra-high range comes alive and a considerably Thrashy Metal feeling comes alive.
It is not the type of sound that I really like, but I thought it would be useful, so I added it through the switch.
The Rockerverb is famous for its unique high-gain tone, but I mainly use the raw and thick feeling with a lot of mid in the medium/low gain.
I feels It is much closer to the British sound than the Marshall-based circuit, like Ecstasy.
You do not have the required permissions to view the files attached to this post.
-
psychepool
- Posts: 286
- Joined: Fri Apr 18, 2014 8:29 am
2 others liked this
Re: Introducing my DIY amps.
==Deluxe Reverb==
Finally, I'll introduce one more additional amp.
It looks a little different from the others, but it's an amp that I still use well.
This amp is a one-channel Deluxe Reverb.
It's an amp that combines the Deluxe Reverb and the Rectoverb clean channel.
The circuit is like below.
It has a reverb and presence knob with the combination of the two circuits mentioned above.
Originally, the Rectoverb's Pushed mod was applied, but it wasn't very attractive, so it was removed.
In order to use the Pushed mod better, PPIMV was applied, but now it's no longer necessary, but there's no reason to remove it, so PPIMV is still alive.
The reason it looks different from other amps is because this amp was made before the Dumble that I introduced at the beginning was made.
Because it's a deluxe reverb circuit, Hammond 1760H OT and 6V6 pair tubes were used.
At that time, I didn't know much about the amp class, so I thought 6V6 pair would be enough volume, but that was when cranked up, and I didn't know that a 15~20W tube amp lacks clean headroom.
There's no need to design the chassis or cabinet size exactly to the component sizes, but since I made it that way, there's no space to bulk up to 40-50W even if I wanted to.
It doesn't make it lighter just because it's compact, and there's no advantage at all, so I think making it like this is just my disease.
Even if I wanted to make a new one after selling it, it's legally difficult to sell a DIY amp in the country I live in.
I have to pass the safety certification conducted by the country to sell it, and if I sell it without safety certification, I' ll be punished.
I wonder how the sales of DIY amps are legally regulated in your country.
I sold all the DIY amps I made before this amp.
This is because the existence of DIY amps was not even known in the country I live in, so there were no crackdowns.
Anyway, this amp is one that I have to keep forever that reason, so I have to use it well.
In fact, it is a very good amp for home use.
The low output of 6V6 actually requires less help from the attenuator, so there is less tone distortion,
and it is easy to break up, so it is also better to use with effect pedals.
The built-in spring reverb provides a reverb with a different depth than ordinary reverb pedals, although I could not use a long tank due to the cabinet size.
The magnetic noise of PT occurs due to the cabinet size, but it is not particularly audible unless the reverb knob is set to 12 o'clock.
This is the chassis shape.
It has a very strange shape because the process of making it is actually a bit complicated.
Originally, I bought a 5E3 made on a Laney Cub10 chassis, but the cabinet was too poorly made, so I made a new cabinet. After using it continuously, I realized that the tweed sound was not my taste, so I changed it to a blackface circuit.
I made a non-reverb channel due to the problem of the number of tubes.
I really liked the non-reverb channel. I thought it was a textbook for clean tone.
I liked it so much that I became very curious about the reverb channel. However, it was impossible to make a tube layout for making a reverb channel with the current chassis.
So I tried to make a chassis that fits the cabinet that I had made, and it ended up like this.
This is the state when I first purchased it (5E3)
The cabinet was newly made
Out of curiosity, I temporarily made a blackface circuit with the chassis,
I judged that it would be difficult to build and operate normally in this state, so I ordered a new chassis that fits the existing cabinet, put on a new black tolex, and made a new control plate to complete it. This is the current state.
When I first purchased this amp, I didn't have the know-how to order a cabinet and chassis, but while I had it, I sequentially found a shop where I could order the cabinet and chassis in the desired form at a reasonable price, so this process was created.
Even after making this amp, it took a considerable amount of time to gain the ability to plan and make it in the desired form as it is now.
It was a long journey, and it was very enjoyable during that time.
I have a job that does design, and when I work on a project, even if I suggest an idea, there are many cases where the result is different from what I intended due to various reasons such as lack of understanding between each other or practical constraints. However, this hobby provided me with considerable catharsis because it is an act of taking the idea I planned to the final result.
Finally, I'll introduce one more additional amp.
It looks a little different from the others, but it's an amp that I still use well.
This amp is a one-channel Deluxe Reverb.
It's an amp that combines the Deluxe Reverb and the Rectoverb clean channel.
The circuit is like below.
It has a reverb and presence knob with the combination of the two circuits mentioned above.
Originally, the Rectoverb's Pushed mod was applied, but it wasn't very attractive, so it was removed.
In order to use the Pushed mod better, PPIMV was applied, but now it's no longer necessary, but there's no reason to remove it, so PPIMV is still alive.
The reason it looks different from other amps is because this amp was made before the Dumble that I introduced at the beginning was made.
Because it's a deluxe reverb circuit, Hammond 1760H OT and 6V6 pair tubes were used.
At that time, I didn't know much about the amp class, so I thought 6V6 pair would be enough volume, but that was when cranked up, and I didn't know that a 15~20W tube amp lacks clean headroom.
There's no need to design the chassis or cabinet size exactly to the component sizes, but since I made it that way, there's no space to bulk up to 40-50W even if I wanted to.
It doesn't make it lighter just because it's compact, and there's no advantage at all, so I think making it like this is just my disease.
Even if I wanted to make a new one after selling it, it's legally difficult to sell a DIY amp in the country I live in.
I have to pass the safety certification conducted by the country to sell it, and if I sell it without safety certification, I' ll be punished.
I wonder how the sales of DIY amps are legally regulated in your country.
I sold all the DIY amps I made before this amp.
This is because the existence of DIY amps was not even known in the country I live in, so there were no crackdowns.
Anyway, this amp is one that I have to keep forever that reason, so I have to use it well.
In fact, it is a very good amp for home use.
The low output of 6V6 actually requires less help from the attenuator, so there is less tone distortion,
and it is easy to break up, so it is also better to use with effect pedals.
The built-in spring reverb provides a reverb with a different depth than ordinary reverb pedals, although I could not use a long tank due to the cabinet size.
The magnetic noise of PT occurs due to the cabinet size, but it is not particularly audible unless the reverb knob is set to 12 o'clock.
This is the chassis shape.
It has a very strange shape because the process of making it is actually a bit complicated.
Originally, I bought a 5E3 made on a Laney Cub10 chassis, but the cabinet was too poorly made, so I made a new cabinet. After using it continuously, I realized that the tweed sound was not my taste, so I changed it to a blackface circuit.
I made a non-reverb channel due to the problem of the number of tubes.
I really liked the non-reverb channel. I thought it was a textbook for clean tone.
I liked it so much that I became very curious about the reverb channel. However, it was impossible to make a tube layout for making a reverb channel with the current chassis.
So I tried to make a chassis that fits the cabinet that I had made, and it ended up like this.
This is the state when I first purchased it (5E3)
The cabinet was newly made
Out of curiosity, I temporarily made a blackface circuit with the chassis,
I judged that it would be difficult to build and operate normally in this state, so I ordered a new chassis that fits the existing cabinet, put on a new black tolex, and made a new control plate to complete it. This is the current state.
When I first purchased this amp, I didn't have the know-how to order a cabinet and chassis, but while I had it, I sequentially found a shop where I could order the cabinet and chassis in the desired form at a reasonable price, so this process was created.
Even after making this amp, it took a considerable amount of time to gain the ability to plan and make it in the desired form as it is now.
It was a long journey, and it was very enjoyable during that time.
I have a job that does design, and when I work on a project, even if I suggest an idea, there are many cases where the result is different from what I intended due to various reasons such as lack of understanding between each other or practical constraints. However, this hobby provided me with considerable catharsis because it is an act of taking the idea I planned to the final result.
You do not have the required permissions to view the files attached to this post.
-
psychepool
- Posts: 286
- Joined: Fri Apr 18, 2014 8:29 am
2 others liked this
Re: Introducing my DIY amps.
==Sound Samples==
Finally, I'll end this thread by sharing sound samples of each amp, even though my playing skills are not that good.
Listening to the sound samples, I think I should have spent more time playing instead of spending time building the amps.
Although my playing skills are lacking, I hope you just think of it as an amplifier that make this kind of sound.
Recorded with Ownhammer V30 412 on Capture X.
Thank you for reading the long post,
and thank you again to the members who made this hobby possible!
Gold Lion(Bogner Ecstasy)
Cerberus(SloRectoTwin)
Kampfschwein(Diezel VH4)
Kodiac(Orange Rockerverb)
Finally, I'll end this thread by sharing sound samples of each amp, even though my playing skills are not that good.
Listening to the sound samples, I think I should have spent more time playing instead of spending time building the amps.
Although my playing skills are lacking, I hope you just think of it as an amplifier that make this kind of sound.
Recorded with Ownhammer V30 412 on Capture X.
Thank you for reading the long post,
and thank you again to the members who made this hobby possible!
Gold Lion(Bogner Ecstasy)
Cerberus(SloRectoTwin)
Kampfschwein(Diezel VH4)
Kodiac(Orange Rockerverb)
-
psychepool
- Posts: 286
- Joined: Fri Apr 18, 2014 8:29 am
1 others liked this
Re: Introducing my DIY amps.
*I always write through a translator. I check for errors once or twice after using the translator, but since the text is long, there may be some strange expressions. Please understand.
-
psychepool
- Posts: 286
- Joined: Fri Apr 18, 2014 8:29 am
Re: Introducing my DIY amps.
Amazing work, mate.
I build and repair tube amps. http://amps.monkeymatic.com
-
dorrisant
- Posts: 2768
- Joined: Tue Sep 21, 2010 1:27 pm
- Location: Somewhere between a river and a cornfield
- Contact:
1 others liked this
Re: Introducing my DIY amps.
Very nice collection! And you know that I dig the compact builds like this. Kudos!!
"Education is what you're left with after you have forgotten what you have learned" - Enzo
-
psychepool
- Posts: 286
- Joined: Fri Apr 18, 2014 8:29 am
1 others liked this
Re: Introducing my DIY amps.
Thank you so much for always helping me out!
Compact builds are something that we may regret while building, but once complete them, we will feel a great satisfaction!
Re: Introducing my DIY amps.
I’m seriously blown away from the talent and effort that is shown on this thread. Thank you, psychepool… 
Greg