Favorite Caps In Vintage Marshall Circuit?

[LLL]

(not the filter caps; the tag board caps)

So I've just about wrapped up my parts shopping list for my Marshall modding adventure after mucho research.

This time I'm going with Sozos than my usual Mallory 150s.

For bypass, with the exception of the split cathode bright side Ck (a Sozo .68uF), there's ceramic disc.
(ceramic also for brite cap)

I'm also trying a well-kept "secret" of Marshall in that in the very late 60's, only for a couple years, did Marshall
put a .68.uF bypass cap over V2a resistor. This boosts gain.

I've had Mallory 150s in there all this time, but supposedly the Sozos have the "magic smoke".

We shall see.

I have some Solens ("fast caps") from France but I was always skeptical of putting hi-falutin' "corquesniffer"
caps in my "GFY" mutt Marshall. :lol:

So for me up to this point, Mallory 150s + ceramic caps.

 

[LLL]

Re: Favorite Caps In Vintage Marshall Circuit?

Anyone? Bueller?

What's your fave caps in a Marshall circuit?

 

[Darg1911]

Re: Favorite Caps In Vintage Marshall Circuit?

Mallory. Cause that's all I've used in a "Marshall".

 

[LLL]

Re: Favorite Caps In Vintage Marshall Circuit?

I'd like to hear from anyone who is an Orange Drop fan in Marshall... :naughty:

 

[jeremy]

Re: Favorite Caps In Vintage Marshall Circuit?

i like orange drops in bf fenders since they have a little more forward mids or at least theres something different going on there. i prefer mallorys in tweeds and marshalls. ive only used sozos in amp repairs, not ground up builds. but if it comes down to it, ill use whatever i can put my hands on if it means not waiting for something to ship

 

[Joey Voltage]

Re: Favorite Caps In Vintage Marshall Circuit?

Anything that fits. I'm not too concerned about what is used and neither was Marshall. They used what ever they could find and was plentiful. Often it was mustards, but I have seen all sorts of things used. One '68 plexi I had in shop had mostly huge blue/white poly film/foil types. they were the stock caps. Also the Treble, Mid, and bass pots were all audio taper as well. Marshall did this early on from time to time. That's a more hidden, or over looked secret than the second .68uf cathode bypass, which is pretty well documented.

All that said, there is very little difference between caps of similar construction and type, especially in the very narrow frequency range a guitar amp operates in. Any difference could be easily seen using a spectrum analyzer, and nobody with wild claims of tonal implication has coughed up the proof yet, so I would take any claims regarding the tone of caps worth a grain of salt especially modern poly caps. There are many more things in the guitar amp that will have a direct influence on the sound than resistors or cap type, especially what you can get your hands on now a days.

 

[Darg1911]

Re: Favorite Caps In Vintage Marshall Circuit?

I thought Marshall started using that .68uf bypass cap on V2 when they went to split V1 cathodes. Leads and Super Leads in the late 60's to very early 70's? But I'm not a Marshall historian in the least. Plus, like Joey writes, they were notorious for being consistently inconsistent.

 

[Joey Voltage]

Re: Favorite Caps In Vintage Marshall Circuit?

I thought Marshall started using that .68uf bypass cap on V2 when they went to split V1 cathodes. Leads and Super Leads in the late 60's to very early 70's? But I'm not a Marshall historian in the least. Plus, like Joey writes, they were notorious for being consistently inconsistent.

They started doing it sometime in late ‘68, and it did last until the 70’s. There were a bunch of other quirky things in some of these amps through that time period. I’ve seen a lot of them. They have also used the 2.7k//.68uf combo on both v1,and v2, as well as 820R on both as well. -fb surrounding the power amp has been been different through the years, the audio taper tone controls I have mentioned, the Ht voltage. So there are a ton of quirks with Marshall during that time, they were notorious for it

 

[LLL]

Re: Favorite Caps In Vintage Marshall Circuit?

I thought Marshall started using that .68uf bypass cap on V2 when they went to split V1 cathodes. Leads and Super Leads in the late 60's to very early 70's?

Not 100% precise, but '68 at the very least and only a year or two (looks like up to around '72).

Funny thing is, the "official" split cathode normal & bright channel Rk/Ck in 1968 has been 820+330uf / 820+.68uf... and 820+330uf / 2.7k+.68uf.

 

[Joey Voltage]

Re: Favorite Caps In Vintage Marshall Circuit?

1987'2 had their own set of variations as well, especially in the 70's

 

[Darg1911]

Re: Favorite Caps In Vintage Marshall Circuit?

I use the 2.7k/.68uf and 820/330uf
Also the .68uf bypass cap on V2

edited due to dyslexia ...

 

[LLL]

Re: Favorite Caps In Vintage Marshall Circuit?

I use the 820/.68uf and 2.7k/330uf
Also the .68uf bypass cap on V2

(I think you meant 820/330uf and 2.7k/.68uf)

For my amp surgery, I'm going with 820+330uf (normal) & 820+.68uf (bright).

 

[Darg1911]

Re: Favorite Caps In Vintage Marshall Circuit?

Yeah, I flipped my values. Just edited my post. Thanks.