Tightening up a 50w

[d20]

Alternatively, use the Jose master without the diodes - works great with plexis and keeps the amp sounding fat even at low volume and gain.

Where can I find out more about this Jose master without diodes? Is there a layout or schem? Does it add a tad of gain anywhere?

Haven't tried it myself but here it be.

I'll have to add this to my 1959.

Thanks!

[Kapo_Polenton]

Thanks cootboy!

[Coot Boy]

Thanks cootboy!

[Kapo_Polenton]

One bit of info we are missing is.. what type of zener diode is that? It must have a value of some type? (not the same as regular diode I am assuming)

[4styx]

Well I'm back finally.The screen resistor was cooked on V4.
Had to go from a 47K to a 33K bias resistor to get enough milliamps.
Everything sounds nice and tight now.Thanks for all the replys.
Kapo your amp sounds pretty good BTW.Does the .0022 on V1a add treble?
My amp is a little on the bright side already.

[Kapo_Polenton]

Does the .0022 on V1a add treble?

Not really treble but it focuses or tightens the tone in my opinion. I like that in my 3 amps the best. Slight difference to my ears.

[PCollen]

Well I'm back finally.The screen resistor was cooked on V4.
Had to go from a 47K to a 33K bias resistor to get enough milliamps.
Everything sounds nice and tight now.Thanks for all the replys.
Kapo your amp sounds pretty good BTW.Does the .0022 on V1a add treble?
My amp is a little on the bright side already.

The .0022 plate coupling cap does not add highs, but it does subtract (block) lows . The capacitive reactance, Xc, is inversly proportional to capacitance and frequency: Xc = 1 / (2 x pi x C x Freq) = .159/ C x F . So at any given frequency, as you make C smaller, you INCREASE Xc which is the capacitors equivalent to resistance.

[Kapo_Polenton]

Yep, What he said.. . I always roll with the .0022 in that position. I guess I just like a tight sound. Cuts through the mix.

[PCollen]

In my amp, I used the .022 caps for all coupling caps.I thought the .0022 on the bright channel took out too much lows too early in the signal chain. All the low end roll-offs are cumulative throughout the pre-amp, starting with the 2.7K/0.68 network on the V2b cathode, so I did what I could with each stages Rk/Ck, and then passed it along to the next stage through .022's.

[Kapo_Polenton]

Well, I tried the Jose master volume mod in this thread and to be honest, the tone is a tad fuller but not that much more gain. I'm wondering if I missed something or if there are other changes to be made elsewhere in the preamp because I don't hear that much of a diff from stock.

[johnnyjellybean]

Bringing this thread back up. Do the zener diodes work on a regular pre-PIMV? I tried it and the change seemed so subtle that it was hard to tell if there was any change at all. I finally left them in because it did seem to change something in the top end although maybe I was just succumbing to a placebo effect!

[rockgod212]

hope this thread aint dead. got a couple of questions. ive seen a few schems put the cap before the 10k resistor coming from CF, should the 10k come off the CF into the cap then into the pot? im a bit confused by this. also all i have are 1n4742- 12 volt zeners, will they work? do connect the 2 zeners the same way as in the diagram? can you use a symetric clipping with the jose style master? how do i get max. using a jose master, as i have it wired right now doesnt seem very loud, hence the questions?

[/quote]
I'll have to add this to my 1959.

Thanks![/quote]

[Reeltarded]

Yes, they work fine. The resistor comes before the cap, then the cap, then the pot. The diodes oppose each other across the outside lugs. Just like the layout there.

With the volume wide open there will still be some reduction in this circuit.

[rockgod212]

ok thanx for the help with this, rewired it and it sounds good,sounds great with cascade mode. what diodes would you recommend, right now im using a 12v zener and a 1n4007?

Yes, they work fine. The resistor comes before the cap, then the cap, then the pot. The diodes oppose each other across the outside lugs. Just like the layout there.

With the volume wide open there will still be some reduction in this circuit.

[Reeltarded]

I LOVE 2 opposing 1N914. You can get them at Radio Shack. That os what Randall ised to make the RG-100/120 sound like George Lynch and it travels pretty well to the Marshall. It will dump volume, but you will notice when your master is at 8 it's just as loud. (and kicking the walls down)

I use a 10k pot on the end of the diode string to ground so I can dial it in or out. Works great!