Advice/tips on a good 5E3 build

[hermannbjorgvin]

I'm looking at doing a couple of 5E3 builds this summer, one 6V6 and another 6L6 Neil Young modified Deluxe.

I'm looking for some tips on making it sing and lowering the noise floor as much as possible

Few questions I have
* Should the 12AX7 pre amp tube be balanced?
* For the Neil Young mods I'm upgrading the output transformer, what should I do on the power section to handle the 6L6's?
* What's your favorite use for the ground switch now?

Other questions: What are the known unknowns or unknown unknowns I am missing?

I have a 5F1 build I have been experimenting on and it's clear that almost any change will change the character of a Tweed amp, do you prefer having certain component values measure lower or higher than the original spec?

Thanks in advance to all the builders

[ChopSauce]

What's a good 5E3?

For some of my mates it's something as true to the original as possible, loaded with vintage components, molded caps, NOS tubes and no speaker made after 1960...

For some others it should have a big OT, etc.

If you live in Europe, Tube Town sells fairly good kits, but at least I'd redo some eyelet boards (from fiberglass not fiber board) myself, for the outcome to look more like the original.

[echuta13]

This is just my $.02 on mods that I've done (and like). Its all subjective and could be argued that it is no longer a 5e3, but is here as food for thought.

I personally like a beefier O/T myself. You could probably find one that does double duty for 6V6 & 6L6. Make sure your power transformer is up to the task as well. Maybe check Allen Amps?

I use 1 watt metal film resistors in my builds to help minimize the noise (especially on grid stoppers, grid leaks, and plates).

The bright channel gets a smaller coupling cap. I like a switch option here for .022 or .0047. The .022 helps cut the flabby/woolly bass (especially with humbuckers) , the .0047 gives a leaner/lead sound. Add a 33K-100K grid stopper on the second gain stage (helpful if you have a 12AX7 in the pre).

You could split the cathodes on the first triode and voice/bias to your taste. Add a grid stopper to the phase inverter (470K-1M) to minimize blocking distortion. Bump up the first B+1 (and maybe B+2) power cap/s to 32uf to improve filtering (and maybe firm up the sound). Add screen resistors to the output tubes for some insurance/compression. Bump up the grid stopper resistor values on the output tubes (1.5k doesn't really do much, 10K would be better). Rebias the output section for proper dissipation. 10w+ cathode resistor and 50V+ rated cathode cap recommended for output section.

You could also elevate the heaters to potentially cut some filament hum as well. I run the 6.3v center tap to the output tubes cathode for DC. I also do not use the stock layout of the 5e3, but that is more for my own OCD and preferences.

I also feel that the Deluxe cabinet is on the small side. The amp could benefit from a cab that was a bit bigger. Adding a couple inches to its depth would definitely help.

[ChopSauce]

If you split the cathodes of V1, several people appeared to like having a 680nF bypass cap on the normal channel.

To answer your questions, there does not seem to be much need for a balanced V1 yet it shouldn't hurt either, and on my build I have been substituting the ground switch with a VVR pot. It was "no problemo" because I started with a chassis blank. I'm not sure it would fit without shouldered washers or other adapters on a normal 5E3 chassis.

By the way: have you seen the Tweedle Dee Deluxe https://ampgarage.com/forum/viewtopic.php?f=5&t=25599 files?

[hermannbjorgvin]

I run the 6.3v center tap to the output tubes cathode for DC. I also do not use the stock layout of the 5e3, but that is more for my own OCD and preferences.

On my 5F1 I ran the center tap from the pilot light and grounded the pilot light to the chassis and soldered the resistors to the light socket, came out pretty clean.

I agree with lifting the filament wires, the run under the board doesn't make a lot of sense for a one off build.

I think I'm gonna go with one stock NOS build but incorporate the coupling cap mod on the bright channel with some metal film resistors then.

The Neil Young one is more tricky I think since it requires a brownface OT, mercury magnetics makes a replica from measurements of the same model Neil's 5E3 has

[hermannbjorgvin]

If you split the cathodes of V1, several people appeared to like having a 680nF bypass cap on the normal channel.

To answer your questions, there does not seem to be much need for a balanced V1 yet it shouldn't hurt either, and on my build I have been substituting the ground switch with a VVR pot. It was "no problemo" because I started with a chassis blank. I'm not sure it would fit without shouldered washers or other adapters on a normal 5E3 chassis.

By the way: have you seen the Tweedle Dee Deluxe https://ampgarage.com/forum/viewtopic.php?f=5&t=25599 files?

Thanks for the tips, I've seen the Dumble tweeds but for these builds I think the stock tweed sound (at least for one of the builds) is the way to go, one is going to a real old school guy and the other is my attempt to recreate part of that Neil Young sound.

Speaking of the Neil Young bit, I've seen differing opinions on what you need to pull that off, supposedly they just changed out the OT but they must have done some other changes to the power stage to handle that

[ChopSauce]

Well, I'm not sure at all about the origin of the Neil Young sound but I couldn't resist the appeal of that wild grawl, so I'd be please with you to share the relevant informations here.

I'd start with finding the right speaker and the model of the pickups he uses on his guitar, though. From hearing the demos of the Deluxe and the Proluxe (6L6 sort of Deluxe) I feel like the difference between both lies more in the amplitude/dynamics than in the tone.

Now, speaking about 6L6 within a tweed Deluxe, provided you have enough current, I could read that you can do anything in between using them in a degraded mod like these have been 6V6s or exploiting at their maximum, provided you change almost anything around.

For what's worth...

... & yes: I also am looking for a clever grounding schema, preferably using isolated jacks (Switchcraft plus shouldered washers)

[hermannbjorgvin]

Well, I'm not sure at all about the origin of the Neil Young sound but I couldn't resist the appeal of that wild grawl, so I'd be please with you to share the relevant informations here.

I'd start with finding the right speaker and the model of the pickups he uses on his guitar, though. From hearing the demos of the Deluxe and the Proluxe (6L6 sort of Deluxe) I feel like the difference between both lies more in the amplitude/dynamics than in the tone.

Now, speaking about 6L6 within a tweed Deluxe, provided you have enough current, I could read that you can do anything in between using them in a degraded mod like these have been 6V6s or exploiting at their maximum, provided you change almost anything around.

For what's worth...

... & yes: I also am looking for a clever grounding schema, preferably using isolated jacks (Switchcraft plus shouldered washers)

I wonder how you'd pull off a complicated grounding schema in such a small chassis, shouldered washers would be a plus.

On the Neil Young side what I've been able to gather is that the 6L6's are almost a drop in, needs a 10W250k cathode resistor and a 50v25uf cathode bypass cap but the OT kept burning out so they replaced it with a brownface deluxe OT. From some calculations on https://thesubjectmatter.com/calcptcurrent.html it seems to work (provided a 3A 6.3v).

For the speaker I managed to snag a 1964 Jensen C12n in perfect condition from a Hammond. It distorts at really low volume and in a very unique way, so it's definitely a key component.

I also managed to find a cheap pair of NOS RCA 6L6GC black plates, fairly well balanced, close enough for me.

[JD0x0]

IMO, to really make them sing, you want to get rid of the blocking distortion. IMO the amps sound and perform better like that, and they will also take pedals better. The downside is, if you like that Farty Neil Young sound, you kind of need that blocking distortion.

4:26 is a great example. That farty/fizzy quality on the attack is largely due to blocking distortion of the stock circuit, which passes FAR too much low end that isnt even being utilized due to the speaker/cabinet used.
https://www.youtube.com/watch?v=TiX8Rz5C3LY

[hermannbjorgvin]

IMO, to really make them sing, you want to get rid of the blocking distortion. IMO the amps sound and perform better like that, and they will also take pedals better. The downside is, if you like that Farty Neil Young sound, you kind of need that blocking distortion.

4:26 is a great example. That farty/fizzy quality on the attack is largely due to blocking distortion of the stock circuit, which passes FAR too much low end that isnt even being utilized due to the speaker/cabinet used.
https://www.youtube.com/watch?v=TiX8Rz5C3LY

So we're talking PI grid stopper or master volume to smooth out the overdrive tones? Sounds like a good idea, I think I'll have to give it a go with alligator clips and see how it sounds

[JD0x0]

IMO, to really make them sing, you want to get rid of the blocking distortion. IMO the amps sound and perform better like that, and they will also take pedals better. The downside is, if you like that Farty Neil Young sound, you kind of need that blocking distortion.

4:26 is a great example. That farty/fizzy quality on the attack is largely due to blocking distortion of the stock circuit, which passes FAR too much low end that isnt even being utilized due to the speaker/cabinet used.
https://www.youtube.com/watch?v=TiX8Rz5C3LY

So we're talking PI grid stopper or master volume to smooth out the overdrive tones? Sounds like a good idea, I think I'll have to give it a go with alligator clips and see how it sounds

Smaller coupling caps, smaller bypass caps, grid stoppers for power tubes and PI input.

There's quite a few Fender circuits where you can cut bass without audibly cutting bass. A guitar amp doesnt need or benefit from a -3dB bass roll off at ~4hz.

For example, 100nF PI couplers give around 5hz -3dB cutoff point with 220k grid resistors. If you reduce those couplers to 22nF you move the -3dB roll off up to about 25hz. This is still right at the limit of human hearing, and no where near anything your typical guitar cabinet and speaker are able to reproduce. So you've virtually not changed the frequency response of the amp audibly whatsoever.
A big difference you'd notice is the bias excursion, though. When the power tubes are clipping, with the 100nF caps there's about a 28.8 millisecond recovery time for the bias. With 22nF couplers that's reduced to about 6ms and grid clamping is reduced.

https://www.ampbooks.com/mobile/amplifi ... excursion/

This can be similarly done in each stage with the coupling and cathode bypass caps. It will help reduce blocking and you can utilize smaller grid stopper resistors. The typical 1Meg value suggestion for the PI input will roll off highs audibly, which may be undesirable, for example. Reducing the grid leak resistor and coupling cap there can reduce blocking, so such a large grid stopper value may not be needed.

[rooster]

That 'farty sound'. It might surprise you to learn that Wes Montgomery's favorite recording amp was a tweed Deluxe with an Jensen P12N. This is according to Wolf Marshall.

The other info I have on the subject comes from a conversation I had with Patrick at Mercury Magnetics. Yes, they did put an MM OT in that amp, but I was told that they ALSO replaced the original PT to a direct bolt in 'more substantial' version delivering slightly higher plate voltage. In fact, he said they tried a couple different PT versions before deciding on the one that is in that amp now. He made it sound like MM was quite into the project, as if they actually had the amp in house at one point. It seems like a great opportunity for an endorsement by Neil for a tranny set but I've never heard of such a set. Still, you might be surprised if you called MM, told them of your dream amp here, and asked them if they 'had any ideas or recommendations?'. But have your wallet ready, MM doesn't give their trannys away.

[dcribbs1412]

You might take a look at the Dumble Tweed Deluxe or Tweedle Dee.
In the Dumble file section.
One of the better Tweed Deluxe circuits I have heard. IMO

D

[hermannbjorgvin]

That 'farty sound'. It might surprise you to learn that Wes Montgomery's favorite recording amp was a tweed Deluxe with an Jensen P12N. This is according to Wolf Marshall.

The other info I have on the subject comes from a conversation I had with Patrick at Mercury Magnetics. Yes, they did put an MM OT in that amp, but I was told that they ALSO replaced the original PT to a direct bolt in 'more substantial' version delivering slightly higher plate voltage. In fact, he said they tried a couple different PT versions before deciding on the one that is in that amp now. He made it sound like MM was quite into the project, as if they actually had the amp in house at one point. It seems like a great opportunity for an endorsement by Neil for a tranny set but I've never heard of such a set. Still, you might be surprised if you called MM, told them of your dream amp here, and asked them if they 'had any ideas or recommendations?'. But have your wallet ready, MM doesn't give their trannys away.

That's amazing info, thanks so much! I'm surprised they beefed it up considering how it's supposed to be his favorite Deluxe.

Definitely a dream project for me so I'll contact them about seeing about maybe getting a set of these. I've read they replicated his OT from an original brownface and they do sell replacements for brownface deluxe's.

[rooster]

Good luck on the quest there. BTW, I played music with this very interesting cat years back, he plays harmonica, and not just blues harp. He's a bit of a character but talented. Anyway, he was a big fan of Neil Young. He actually worked as as grounds keeper/guard at Neil's home in CA, Broken Arrow Ranch for a brief time years ago he said. He told me that Neil had a couple of 'large metal storage garages' on the property at the time. He was never allowed to see or go inside any of the buildings but he said he was talking to a guy there who was familiar with things and one day, in passing conversation, the guy said that Neil had a lot of those tweed amplifiers in this one building. My friend asked him, did Neil have like 10 (?), and the guy said he 'had over a hundred of them in there, they were stacked up in there'. Haha, I found this kind of crazy news but I will never know if what he told me was true. He was always straight with me and we worked together for 6 months so I believed him. His wife had to transfer back to CA to make some serious money as he wasn't working a job while he was here. He called a few times since but we've lost touch.

Anyway, I think about that storage garage from time to time. Neil certainly has the money to buy a few amps and he may need a backup or two.