Ultraphonix adventure

[fred.violleau]

Found the issue, bias was too cold.
Need to swap resistors but in the meantime alligator clip is more than enough to play the beast and bias it to 40mA with 422V plate voltage

I change the value of the mid pot for a 100k, I love the tweedier clean tones, feels like the amp is right there in your face. Very punchy cleans. Dirt is good, but I would have enjoyed more mids. I will try a few different speakers and report back.

I have played my usual TC reverb and delay in the FX loop, located
after the relay that allows me to switch from clean to mean, exactly like Dumble would do. Reverb in the loop is adding overdrive and limits a wee bit the original output... Will check voltages against other builds at this point, maybe too hot for the device...

I think I will also try to swap 6L6s for el34. I think the trafos should be able to handle it.

Here is little clip of clean and mean channel:

https://youtu.be/Rx43TRFx8nQ?si=bb_Bhqh8Ib2M9HCi

Again thanks for all the information shared on this forum, could not be possible fore to have fun building these otherwise!

Fred

[Guy77]

Looks and sounds Fantastic Fred. Congrats!

Guy

Cheers

[ijedouglas]

Sounds fantastic! Funny, I actually found the clip, was listening to it first and then came here to see if you had posted about it

[fred.violleau]

Hey Ian, Guy, thanks for the kind words!

Fred.

[bepone]

best of 2 worlds!

[Reeltarded]

Hey Ian, Guy, thanks for the kind words!

Fred.

You have built two of my favorite amps now! This one sounds as amazing as the Tweedle!

Great job!!

[dorrisant]

Sounds great Fred! Awesome job

[rayrayman]

Sounds great, and the switchable channels is a really nice touch.

Thanks for sharing some pics

[beasleybodyshop]

Sounds fantastic! Bravo Fred.

[Reeltarded]

Sounds fantastic! Bravo Fred.

Build it!

[fred.violleau]

Double post

[fred.violleau]

Again thanks for all the help and kind words. This quest for tone is enabled by guys like you, sharing without limit what you have documented, experienced. I am very grateful to this community!

Agreed, the Tweedle Dee is also the amp I have played most. Second is ODS between 183 and 102 that has a fantastic mid range on the OD side. I used to play a lot with the classic overdrive, but last time I fired it up, did not bond with it.

This one has a lot of punch on the cleans (due to the 100k mid pot) that I really dig. I guess I really enjoy the tweed style amps as the Tweedle Dee has that kind of "in your face" cleans. I wish I could get that mid bump on the OD. It sound very good, but there is a "but" and I can't yet articulate it precisely.

I have to finalize the NFB value, do the footswitch, find a fix for the signal level entering the loop FX (maybe a voltage divider?) and redo the tolex on the cabinet. Will try to post more sound sample this weekend. From the clean and dirt channels this weekend.

Again, thank YOU, as I really dig this one too. Can't stop playing it!

Fred.

[Reeltarded]

Lovely! I have an idea for you.. this might require a small resistor to partial the bypass.

.0022u over OD mixer. I am unsure how it will play with the clean side, but you can trim it to match perfectly and adjust the cap value for peak range.

I think this is exactly what I found on my 'inspired by' mule build. Adding a bit of bypass there makes it as forward and even angrier than some of my amps with more stages. Beastly, even.

Instead of a divider, think about grid leak in the way third stage of TW Express/Liverpool at your loop input side? I need to look at your amp again..

Again thanks for all the help and kind words. This quest for tone is enabled by guys like you, sharing without limit what you have documented, experienced. I am very grateful to this community!

Agreed, the Tweedle Dee is also the amp I have played most. Second is ODS between 183 and 102 that has a fantastic mid range on the OD side. I used to play a lot with the classic overdrive, but last time I fired it up, did not bond with it.

This one has a lot of punch on the cleans (due to the 100k mid pot) that I really dig. I guess I really enjoy the tweed style amps as the Tweedle Dee has that kind of "in your face" cleans. I wish I could get that mid bump on the OD. It sound very good, but there is a "but" and I can't yet articulate it precisely.

I have to finalize the NFB value, do the footswitch, find a fix for the signal level entering the loop FX (maybe a voltage divider?) and redo the tolex on the cabinet. Will try to post more sound sample this weekend. From the clean and dirt channels this weekend.

Again, thank YOU, as I really dig this one too. Can't stop playing it!

Fred.

[fred.violleau]

Found a way to tame the output in adding a d-lator in between.
Works pretty well !

I have tried a different EQ on the dirt side and 3'o clock for treble and mid while bass is almost off seems to do the trick. I get the anger without the flab of the bottom end. It remains defined and not too compressed.

I don't have mixer resistors: I put a relay instead and I change the mixer resistor value with the relay. I thought it could act as a sort of boost.

So my first relay outputs clean/dirt signal and grounds the other, feeding the FX loop, then into the second relay where I get to choose between 2 combinations of resistance : 220k and 220k up to 470k, or 0k and up to 220k. (220k resistor and 250k pot).

But I did not setup the mixer resistor as a voltage divider, so it does not have the boost effect I was expecting. Need to revisit this.

Your proposition is to bypassed the mixer with a .002uf cap to bring more mids? Gotta try and see what effect it has on both channels.i could also bypass the volume knobs on the dirt channel only, so there would have no effect on the clean side.

Fred.

[Reeltarded]

I see..

I would do the switching opposite and this would fix everything in 3 parts with 10 minutes of heating metal. I would switch at the..

You know, I just realized differences in how people think about circuits. Why you did what you did just unfolded like space-time. The reason people suggest that an amp be totally rebuilt when looking at beautiful gut shots of a guy with a simple grounding issue.. the scrunched up face when someone starts negging the normal side of a totally stock VIB Fender amp when the OP is having an issue with the trem.

I got nothing to say! Except a window into my way BUT DONE YOUR WAY!!

You could put some resistance on the OD side of switching and bypass there.. EASY to pick corner frequency and go with a resistor that won't really affect anything based on what is on either side. (of switch)