2203 mod help

[core]

Notice the wires going to the "turrets" at the right end of my board, both my 78's have the turrets, wonder why yours doesn't?

Also your screen grid resistors are discolored from over heating, i'd have them replaced & filter caps if they're original.

Can't answer specifically but Wilder once told me that the turrets could either be there on not or have different connections all depending on specific electrical needs due to whatever they deemed. Most likely country specifics

 

[krokit]

Can't answer specifically but Wilder once told me that the turrets could either be there on not or have different connections all depending on specific electrical needs due to whatever they deemed. Most likely country specifics

Mmm.. interesting. As you mention, could be country specific then?

Thanks bud. I notice you use a Flying V with 'the beast'...aint it a wicked combination.

 

[krokit]

Update:

I checked the bias and re-set it to 36ma as it was set pretty cold, the plate voltage was 480. As soon as I hit a chord it sounded SOOOO.. much better! So out of curiosity I put the 68k resistor back onto the wiper and hit a chord... fuckin wicked! Fat and sooth.. Now I can turn up the presence (from zero) with out harshness!

Now I wanna try some new preamp tubes and am thinking about tung sol?? Ive been searching through the preamp tube threads and now Im suffering from information overload! So many options! Maybe just 1 tung sol in v1?

Ive got jj el34s by the way.

Many thanks for all the help guys

 

[Bieling3]

I tried an RCA, Mullard RI and TAD in the v1 when I had a 800, all were great. Anything else, EHX, JJ, etc, increased the background noise/hiss noticeably.

 

[krokit]

I tried an RCA, Mullard RI and TAD in the v1 when I had a 800, all were great. Anything else, EHX, JJ, etc, increased the background noise/hiss noticeably.

Cheers Bieling3. I'm wondering if its worth just replacing v1 or all 3? Ive noticed a lot of people using 3 different preamp tubes which sounds interesting! Did you ever try this?

Thanks again.

 

[Bieling3]

I settled on the TAD in V1 and the RCA in V2... I think I had a plain old jj in v3 (phase inverter is supposedly not to important tone wise, just has to be stout).

 

[krokit]

I settled on the TAD in V1 and the RCA in V2... I think I had a plain old jj in v3 (phase inverter is supposedly not to important tone wise, just has to be stout).

Cheers bud. I might just try that combination.

 

[zaboocat]

looks like you used 1/4 watt resistors when you should of used 1/2 watt resistors, so it cannot handle the load. I have 2203 ri did the same mod works perfectly at all volumes I also up grade to Sozo capacitors. I have a marshall 1959 HW that I converted into a 2203 and up graded to nos mullards that incredible too! It appear to be a 1959 but it is 2203 in disguise. I would never mod a vintage marshall it goes against the laws of nature.

 

[damienbeale]

Don't think he's still here four years later...

Modern 1/2w resistors are half the size of the originals on the board. But by the sound of it, the original problem was oscillation anyway. This thread was chock full of crap and misinformation, even from the major, which was a little surprising...