Marshall 2204 Bright Cap

[8bit Barry]

A year or so ago I got my tech to take out my bright cap on the 2204. I always use it with an Ironman attenuator.

The amp spends most of its time with the volume at 4/5 and the preamp sound 6/7.

Am I really missing out on having a bright cap? I keep reading it’s part of the Marshall sound and I am starting to think I should put it back.

Before the Ironman, the amp was so bright I used to run it with the presence and treble on zero, master volume was of course on 2 to avoid being deaf!

What was the original value of the bright cap?

What would you do?

 

[dtier]

Its a .001 micro farad ceramic originally. I like it in. Did you happen to watch Jason Tongs (Headfirst) video on the subject? He A-Bs it at around the same gain setting on a 2203.

 

[Jethro Rocker]

I just lifted one leg on mine. Easy to put back.
I normally run gain full up but the odd time I need it lower, it now still sounds the same. If you like it, leave it cut.

 

[JTM1963]

Check out this Pete Thorn video on YouTube:
ONE LITTLE PART, HUGE EFFECT ON TONE! BRIGHT CAPS in MARSHALLS

 

[LyseFar]

I removed it for a while from my Super Lead - now it’s back in. Like it best that way.
Also present in my 2204. Stock is the way to go I think. At least for my ears.

 

[79 2203]

I’ve always been a believer in stock bright caps and usually run the Preamp on my 2203’s around 5-7. Currently I run it at 7 on my stock 79 using LP Specials with either P90’s or Pearly Gates. Of course at home it’s gonna be abit bright but in a loud mix these amps sit perfectly.
Playing at home I’m going straight in, and even with either guitars bridge tone control on 5(Vol 10 or close to it) I have to keep the amps Pres off and Treb on 2.
But here’s the thing, I also keep the Bass on 2 primarily because I find my 79(and to a lesser extent the 80 and 82 2203’s I’ve had) to be abit scooped, so I’m running the Mid on 10 and have to keep the Bass low to let the mids through. In any case, I hate a lot of bottom end for the 60’s/70’s classic blues rock I play.

And speakers/cabs have a huge influence on your experience with a stock bright cap Marshall. With my 77 slant with the original 55hz 30 watt Blackbacks on top and 2012 V30’s on bottom, the tone is bright and edgy, but with a July 68 straight cab with original Pulsonic 25 watters the high end is much smoother and the mids fill out abit.

So as much as I’m enjoying my stock 70 Super Bass(no bright cap)with its warmer, less aggressive, cleaner tone, I have to keep the Bass off and Treb, Pres on 10 to get the tone I want out of a classic Marshall. And it doesn’t quiet clean up as well as the 2203 or stock 71 1987.

 

[dtier]

A lot of great observations here relating to speakers, gain and volume, as well as 50vs 100 watt models. If your open to modifications you can install a push/pull gain pot to switch the cap in or out.

 

[Emiel]

I'd look at speakers. It shouldn't be too bright with G12M25s or G12-65s...

 

[Chris-in-LA]

What was the original value of the bright cap?

It's usually 1000pf on 2204's and 2203's if I'm not mistaken. That's what's in mine and that's they have on the schematics.

 

[mickeydg5]

Some 2204 had 1000pF while others 5000pF. I my opinion too large especially the 5000pF/.005uF capacitor.
The tweed Bassman had 100pF as did the JTM45.
I would keep a low value capacitor before I removed it totally. It gives the tones.

 

[AndyD]

Its a .001 micro farad ceramic originally. I like it in. Did you happen to watch Jason Tongs (Headfirst) video on the subject? He A-Bs it at around the same gain setting on a 2203.

Any chance you could share a link, please?

 

[Point 2 Point]

W

I removed it for a while from my Super Lead - now it’s back in. Like it best that way.
Also present in my 2204. Stock is the way to go I think. At least for my ears.

What year is your Superlead?
Just curious.

 

[dtier]

Any chance you could share a link, please?

 

[AndyD]

Thank you!

 

[LyseFar]

W

What year is your Superlead?
Just curious.

JMP 1980
... as I recall it is a 4700pf bright cap

 

[AndyD]

As everyone have said….leave the bright cap in place. Better trying different preamp tubes. Mullards and RFTs really fatten the tone in these amps.

 

[Point 2 Point]

JMP 1980
... as I recall it is a 4700pf bright cap

In that video he is adding a 1000pf on the ‘76 2203.
Are the bright caps lower on the JMP MV amps vs NMV?
My ‘ 80 2204 is being looked at this week so I’m curious what stock would be.
Thanks

 

[dtier]

1000pf is the same value as .001mf. That the only value that I have seen on the 2203/4 but there may be other values used. The NMV have used several different values or none as well over the years.

 

[Point 2 Point]

Last week Jeff Snider worked on my ‘73 JMP 50w, that I got 6-8 months ago, that was excruciatingly thin and bright.
He moved the presence tap (?) from the 4 ohm to the 8 ohm and put an added resistor to the existing bright cap.
Before resistor.


He described it as non- musical before.
It worked well and still has the bite.
Sorry to derail.

 

[LyseFar]

In that video he is adding a 1000pf on the ‘76 2203.
Are the bright caps lower on the JMP MV amps vs NMV?
My ‘ 80 2204 is being looked at this week so I’m curious what stock would be.
Thanks

I think that the bright cap in my JMP 2204 is 1nF