JB and JCM800

[hanumanlangur]

I was just messing around with the Duncan Amps Tone Stack Calculator, and an idea dawned on me. Looking at the Marshall tone stack frequency response, it's clear that the lowest frequencies are highly attenuated, and the highest frequencies are rounded off as well.

I think that this frequency response may be responsible for much of the way that the JCM800 seems to work so well with the JB. If we were to fix the JB's EQ, for example, most of us would probably cut out quite a bit of the low frequencies that make the low-end loose, and probably also attenuate some of the highest frequencies, to avoid harsh brightness.

So... I'm thinking that it may be possible to get the main benefits of this by using a variation of Artie's de-mud mod, combined with a tone control with a high cut-off frequency (0.022uf or smaller cap), turned back a bit. If so, that would be the truest "fixed" JB.

 

[hanumanlangur]

Re: JB and JCM800

On a side note, has anyone tried Artie's de-mud mod with the JB in the bridge position?

 

[Benjy_26]

Re: JB and JCM800

Never tried it in the bridge, but it works wonders in the neck slot with a bass heavy 'bucker like a 59n. I can see how that mod would work with a JB, kind of like hitting the bass cut button on a mixing board.