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I noticed the volume pots on the 5E3 have very limited range and have been told this is inherent to the original design. I would like to install the 6G3 Brownface Deluxe volume/tone mod described under Tone Tweaking on pg.46 in the build manual. Does anyone know how I would do this?

This is noted as: "Use the same Volume and Tone circuit as the 6G3 Brownface Deluxe. The reason for installing this mod is that the standard Deluxe ramps up fast and breaks up very soon with not much useable range in the volume pots. The tone/volume mod fixes that and at the same time smoothes out the response and volume curve. Plus it reduces the dark muddy tones as you play louder. After this mod is installed both channels are a little brighter and cleaner. The normal channel is more useable and the bright channel is special with better highs and note definition, while the amp doesn't crank out until the volume pots are around 4.5-7 instead of 1.5 to 3."

I expect you will loose the interactivity of the two volume controls. Try that Interactive control first and see if you can get what you want.



as opposed to the 5E3 circuit.

5E3 Volume Schematic

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

[list=]Connect a 220K resistor to the wiper of each volume pot.
Connect the other ends ofthe 220K resistor together
Connect that end to pin 2 of V2.[/list]

Let us know how it works for you.

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Very interested in knowing how this works out.

Actually plan to have Percy Adler try this out tonight. He's very critical so expect good feedback tonight.

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Anything yet to report on this mod, Stephen? Thanks.

I tried out this mod last night and didn't like it. It reduced the abruptness of the volume pot increase, true, but at least on my amp it also killed a lot of the high end - made it way too midrangey.

For clarity and high end sparkle, I still prefer playing into the bright channel (either one or two), setting that volume around 3, and setting the normal volume to max, maybe slightly less. Those interactive volume pots do have a strong influence on each other (see the manual).

Same setup, but decreasing the normal volume pot to around 5 adds a substantial amount of midrange and accompanying overdrive. But for a sweet dirty tone I prefer to keep the amp as clean as possible and use a good pedal in front. Just my taste...

Try bypassing each resistor with a small capacitor (50pF-500pF). This will bring back the high end while keeping the channels "independent" of each other.

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Ah, yes, I forgot that simple rule of physics! Thanks.

We never got to the mod but we made huge strides for Percy's tone.

His amp now has:
VRM
PI 470K grid stopper resistor mod
.022 uf coupling caps on both channels at V1
NO PI 25uf bypass cap.

This hasnt changed the volume controls but made a huge differenct to tone. Headroom to 6 or so, very spanky amp now. Read on.

"Thanks very much for your attention to the Tweed last night. The amp is transformed. The coupling capacitor changes really worked ... and as we noticed, particularly on the bright channel.
I have lot's of headroom, so no issues there.

The tone is so adjustable, on one hand it appears simple but there are so many different nuances with each control. Fanbloodytastic.

more...
I played this amp for probably 5 hours yesterday discovering many little tonal places. I used a full bodied fully hollow archtop (Eastman 805CE), my thin bodied fully hollow archtop (Eastman T146), my Gibson Tennessean, my Tele, and my Jazzmaster.
It does it all."
Percy

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

How did you physically build this? Just curious

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

How did you physically build this? Just curious

I followed your suggestion:
[list=]Connect a 220K resistor to the wiper of each volume pot.
Connect the other ends ofthe 220K resistor together
Connect that end to pin 2 of V2.[/list]

Physically did it with the resistors at the vol. pot wipers, other ends soldered together to a short wire which ran to pin 2 of V2 (the 12AX7). Did I misunderstand your directions? I didn't try the bypass caps kurtlives suggested.

Stephen, it would be very helpful if you could give a little more description of the mods to Percy's amp, in a step by step for those of us w/o the technical expertise; or a reference to the previous threads explaining the various changes. Increasing headroom on the Tweed would be of interest to a bunch of us, I'm thinking.

Regards!
Jim

OK, I think I have this figured out. Stephen or Kurtlives or someone else please correct me if I have it wrong.

Mod for Percy's amp (from Stephen):

PI 470K grid stopper resistor mod
.022 uf coupling caps on both channels at V1
NO PI 25uf bypass cap.

This hasn't changed the volume controls but made a huge difference to tone. Headroom to 6 or so, very spanky amp now.

The grid stopper runs from the 1M resistor (R12) on the board to pin 7 of V2 (the 12AX7), soldered right to the pin 7.
Coupling caps understood (C1 and C2).
Remove the 25uF cap - this is C7, which goes to pin 3 of V2.

Am I right?

Thanks!

See layout for PI 470K grid resistor. But yes your right. download/file.php?id=354&mode=view

Correct about 22nF coupling caps.

PI is indeed C7

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I want to give a brief report on the tone mod Stephen used for Percy's Tweed. Here is the mod:

Add 470k grid stopper resistor for the PI tube (V2, the 12AX7) - goes in series from the 1M resistor on the board (R12) to pin 7 of V2. Replace the 0.1 uF coupling caps (C1 and C2) with .022 uF. Remove the 25 uF cathode bypass cap (C7), which connects at pin 3 of V2.

I am very happy with this mod! It has made my Tweed much more versatile. The interactive volume pots now have much more useable range. The cleanest setting, using the brite 1 input and dialing vol. 2 all the way to 12, is cleaner now with much more headroom. Still very clean backing vol. 2 down to 10 or 11, which adds some rich midrange. Vol. 1 can now be used all the way to 12, with reasonably clean sounds to 5 or 6. Maxed out yields a very fat and sweet distortion, as much as I would ever want.

I do find that, with this mod, the amp sounds best keeping the VRM up at least half way (if not higher) and lowering vol. 1 to reduce volume. The normal input is also more useful with this mod - no longer muddy but still mellower than the brite channel.

I had planned to experiment with low value caps for C7, but I like the sound so much with no cap for C7 at all, that I see no need to do that. If you want better cleans from your Tweed, I highly recommend these changes. Thanks, Stephen, for posting them! By the way, my amp has NOS RCA tubes (including the rectifier, which drops B+ considerably) and a Tone Tubby alnico 12" speaker.

Sounds pretty cool! You should post a pic of your amp.

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Your report sounds very familiar. When I got to eliminating the PI bypass cap, Percy told me to stop - it was perfect. We alsio noticed the much improved Normal channel. All in all, fter subsequent testing with band and solo, Percy reports that it is now "Perfect for my needs."

I would sell every Tweed and Tweed kit this way if I could convince people to depart from the Classic version.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Hi Guys.
I'm reading this with interest, as I want to set mine up in the way people with experience deem the best.
I'm going to be using this amp with a Strat, so I'm not worried about humbuckers. I am using a Tone Tubby Alnico and a VRM.
I think I understand the recommended setup is
1. Add 470k smoothing resistor on pin 7 of V2
2. Replace .1 uf caps C1 and C2 with .022uf
3. Remove 25 uf cap C7

Is that correct?

My question is this:
You are all referring to P1 and C1 and C2 and R12 etc.
My circuit diagram is not labelled in this way. Is there a diagram that I have missed?
I do not know which ones are C2 and C2. I THINK they are the two on the right side of the circuit board but I'd like to be sure. I have figured out which is C7 based on the description of where it is connected in a previous post, but I do not know WHY it is called C7.

Can I buy the components at Radio Shack or should I get them from Stephn to make sure they are correct?

Thanks,
Scott

I hope this makes the mods very clear. I doubt RS has them but you can try. We used Orange Drop caps and carbon comp resistor in keeping with the Tweed design.

Try it the original way for a while. Then make the mods(s) if you want to try it, but I do recommend you try it first.

TWEED MODS

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Ok thanks Stephen. I was just going to go ahead and make the amp with the mods based on your post saying " I would like to ship all amps this way".
Why should I build it stock first if you recommend it modified?