Taming a slightly bright 2203

[junk notes]

I recommend a 68 basketweave resistor rated at 1.21 gigawatts for max flux capacitance best dampening the flow of unwanted electrolytic brightness ;-)

(IIRC Jim Marshall's favorites were the bright ones)

 

[AlvisX]

"Slightly"

That's an understatement . Couple years ago, I did a live video recording in England ,using the studio's 800 2203 . It was early in the morning and I just wasn't thinkin.....it wasn't MY 2203 . I had to use the neck pickup as there was no dialing it out

Anyhoo, my prescription , remove the second 470pf peaker cap ....the one on the board , don't put anything in there
Remove the bright cap from over the gain pot , replace it with that 470pf you took off the board .
Remove the 470pf peak cap over the resistor that runs from the input jack to the pot
Get your gator lip leads out and put 'em on each side of that resistor . Try various capacitors to your taste. Usually I end up using 270pf
Im pretty sure I used 390pf on this one

 

[eastwood6]

Yes but IMO opinion and experiences, they are not that musical and add a lot of compression. This is good if that is what you are after.

Oh, I agree. Don’t like JJs in V1 or V2 at all in any of my amps. But they do tame the brightness of amps that tend to be that way. Sometimes fixing one problem causes another LOL.

 

[Mrmaxelcat]

So my second 2203 arrived yesterday. It's in very good shape but has a new power transformer.

It's running EL34s and was recapped fairly recently. It has blue F&Ts in it.

It's a bit brighter than my previous 2203, actually a fair bit brighter. I'd like to tame that brightness, make it more balanced sounding.

First I'm going to take a look at that bright cap. I suspect it's still there.

Got any recommendations beyond that point? I'd rather ask those who are experienced than just try to wing it. Yes, I could. I'd rather listen to the voices of experience first.

The simple answer is keep the preamp volume on 8+, treble 1.5, bass 8, mods 6, presence 4 ish. When the preamp is up high the effect of the bright cap is greatly reduced. Before doing all this modding it’s best in my opinion to get the best out of what you’ve got.

 

[Mrmaxelcat]

Yeah, me too. Also keep the mids down, they are very bright. I don’t know why guys want to cut the treble cap, just turn the treble, mids and presence to 0. Brown sound for days especially with the gain on 10.

If you turn the mids to 0 you will sound good in your bedroom but with a band you will just disappear and hear jack.

 

[Matthews Guitars]

It's still a fair bit brighter than the previous 2203 at the same settings. I'll make a few recommended component changes, starting with the bright cap and testing one change at a time. I may increase the gain of it a little bit as well. V1A and V1B plate resistors at 150K would probably be a good boost.

 

[Chris-in-LA]

If you turn the mids to 0 you will sound good in your bedroom but with a band you will just disappear and hear jack.

Absolutely right. Brown sound is over-rated. Those amps are bright for a reason, they need to be able to cut through. But, for the living room, that’s a different matter.

 

[Rusty Strings]

Or without any modification to the amp, I can recommend Celestion AType speaker. And they are not expensive either.

 

[Trapland]

So my second 2203 arrived yesterday. It's in very good shape but has a new power transformer.

It's running EL34s and was recapped fairly recently. It has blue F&Ts in it.

It's a bit brighter than my previous 2203, actually a fair bit brighter. I'd like to tame that brightness, make it more balanced sounding.

First I'm going to take a look at that bright cap. I suspect it's still there.

Got any recommendations beyond that point? I'd rather ask those who are experienced than just try to wing it. Yes, I could. I'd rather listen to the voices of experience first.

Valves. If it’s full of current Chinese 12ax7s, those are really hot and bright. Personally I like them.

You can quick test for a bright cap by playing at 6 then at 9-10. If it is significantly brighter at 6, then there’s a bright cap.

There are so so many more places to tweak, but the average non-tech person can start here and often make huge changes. I’m mostly replying for those people, I know you know these things. I assume your thread is for them.

Edit to add: Hopefully you aren’t playing that amp through V30s. I feel V30s are way too bright for pre- late 80s era amps. The amps were not tuned for those. Easiest to change speakers, but if one MUST use V30s, then revoicing the amp may be needed.

 

[Matthews Guitars]

I don't have any V30s. My 4x12s have G12T75s in some cabinets, and Greenbacks in others. This amp likes the Greenbacks a lot more. No surprise, they're my all-around favorite Celestion.

 

[MarshallDog]

I don't have any V30s. My 4x12s have G12T75s in some cabinets, and Greenbacks in others. This amp likes the Greenbacks a lot more. No surprise, they're my all-around favorite Celestion.

I have two G12T75s in stock and I find they are much brighter than geenies or creamies!

 

[Matthews Guitars]

The 75s have a scooped tonal profile to them. Greenbacks push the midrange. They're almost opposites.

 

[MarshallDog]

The 75s have a scooped tonal profile to them. Greenbacks push the midrange. They're almost opposites.

Thats a good way to describe them!

 

[Gutch220]

Maybe look at speakers. This is an easy, non-permanent way to change your sound without mods. Check out some Celestion Redbacks, they aren't as bright as other Celestions, and are on the darker end. Plus they'll easily be able to handle your 2203's 100w+

 

[Matthews Guitars]

Took out the bright cap across the preamp volume control. Far as I'm concerned, that fixed it.

Its tonal center is right where I want it to be now. VERY pleased. Big fat beefy tone with all the treble and harmonics I want, not much more than that.

Incidentally, this 2203 does have the white dipped poly capacitors with blue printing, that some people think are tonally excellent.

I can't argue against that notion. This amp does sound great now that the bright cap issue has been handled.

 

[Trapland]

Glad a simple change was enough. That happens often.

 

[MarshallDog]

Took out the bright cap across the preamp volume control. Far as I'm concerned, that fixed it.

Its tonal center is right where I want it to be now. VERY pleased. Big fat beefy tone with all the treble and harmonics I want, not much more than that.

Incidentally, this 2203 does have the white dipped poly capacitors with blue printing, that some people think are tonally excellent.

I can't argue against that notion. This amp does sound great now that the bright cap issue has been handled.

Dude, I just knew you would like it. Sometimes that is all it takes! If you ever get board with it try a 100 - 110 pF cap...its a nip slip spot on cap IMO!

 

[Matthews Guitars]

I'm going to boost the gain a little for a bit more crunch and sustain. Just going to change out the V1A and V1B plate resistors from 100K to 150K or thereabouts. That should give it a fair gain boost while still allowing it to clean up nice.

I'm THINKING about replacing the 10K cold clipper cathode resistor with a 25K variable pot in series with the 10K. That should allow me to adjust both cold and hot side clipping very easily for a tasty tonal palette.

 

[MarshallDog]

I'm going to boost the gain a little for a bit more crunch and sustain. Just going to change out the V1A and V1B plate resistors from 100K to 150K or thereabouts. That should give it a fair gain boost while still allowing it to clean up nice.

I'm THINKING about replacing the 10K cold clipper cathode resistor with a 25K variable pot in series with the 10K. That should allow me to adjust both cold and hot side clipping very easily for a tasty tonal palette.

Keep it stock and hit it with a pedal!

 

[Matthews Guitars]

Resistors are cheap, pedals cost money. And I don't care for pedals very much. I am very definitely the kind of person who believes that the overdrive should be both fantastic and native to the amplifier itself, and not some external box.

I subscribe to Ted Nugent's Theory of Tone: A great amp, a great guitar, a straight cord, and no noise toys in between to mess up the signal.