Jose Master Volume

Kapo_Polenton

Kapo_Polenton

Well-known member
Let's talk about it without getting into an EVH debate... I tried the specs for the one i saw on the metroforum on my 1987x a while back and found it did very little. Made it sound a tad thicker but not much gainier. What does it do to an 800 circuit? Worth tinkering with or does it sound like buzz saw gain much like lowering the cathode resistor from 10k to something lower can sound in an 800? I can't go any lower than 8.2k for my ears... even at that it is a little too buzzy)
 
I've only ever tried it in a non-MV marshall type amp and didn't think it was worth having. Supposedly it works a bit better in 800 type circuits, but I don't know.

Are you using any transistors or do you have it wired up without them?
 
I think that's what the layout said. Are you using any in particular? One of the posts says to use 1n4747a diodes. Pretty sure the schematic that layout was made from had transistors though...

jose-1.jpg
 
Technically speaking, placing the MV before the tone stack ala jose, cameron, a bunch of other modders, screws up the impedance to the tone stack and makes the tone controls far less effective. Whether you like the sound of it is entirely subjective. If you like the diode clipping place the clipping in the same spot and move the MV AFTER the tone stack where it should be.
 
Ok I just tried it in my 2204 clone... interesting. I don't hear any added gain and I quite like it in terms of being able to crank the master volume of the amp and then dialing back the "jose".. was kind of hoping it might add a little crunchy sizzle but to my ears there is very little.

So that said... makes me wonder how much diff it would really make for someone who we know who used Jose modified amps?? Maybe that is why it "might" have been removed. Anyway no importance, I guess the Jose doesn't add much gain then correct? I think i'll keep it for now, I'm liking it.
 
Actually, using clipping diodes makes the amp "lose" gain. The signal is attenuated to the voltage of whatever diodes, or the diode part of the transistors used. Thus, there is not as much signal to drive the PI, which in turn, doesn't drive the power amp as hard.
 
Also doing some reading, I should have back to back zeners not a diode and a zener. I think I've also got the wrong type of zener as the one referenced in the layout does not appear to be right. That would prob make a diff too.
 
I must have something wrong then.. in addition to using a diode and a zener, I think all i am doing is controlling the volume of my amp. The layout in the thread i posted cannot be right. Does anyone have a link to the correct wiring of the Jose in a schematic? I'm interested in seeing why this is a 500$ mod!
 
The layout is correct. What zener did you use? The level of clipping and how much it clamps the output of the cathode follower there depends on the voltage rating. Lower voltages means more clipping, and less signal. It should be pretty noticeable... I don't know exactly why it's called the Jose master though. The clipping diodes really have nothing to do with the master. Here's an okay article on diode clippers.

http://www.muzique.com/lab/zenmos.htm
 
russoloco":1a1f903q said:
Well the placement of the master volume does have a lot to do with it. The jose places the mv before the tone stack.
Click to expand...

Well, yea, but so do other amps. It's like people calling a simple voltage follower the "Klon buffer". It's not a very good descriptor, or unique to its namesake. Just something that's always bugged me about the gear world as a EE.
 
mmolteratx":9k5jg8d3 said:
The layout is correct. What zener did you use? The level of clipping and how much it clamps the output of the cathode follower there depends on the voltage rating. Lower voltages means more clipping, and less signal. It should be pretty noticeable... I don't know exactly why it's called the Jose master though. The clipping diodes really have nothing to do with the master. Here's an okay article on diode clippers.

http://www.muzique.com/lab/zenmos.htm
Click to expand...
I believe it was named that because Jose may have put the zeners/transistors as part of the master as a push/pull pot.
 
I def need Billy Blades to show me how best to route my wires and goop it up for safety...

I'll check which zener and the voltage that I used when i get in today.. I had this old master kicking around removed from when i tried it in a plexi so i don't recall what i ordered. Pretty sure it was the correct ones though.
 
Kapo_Polenton":44yh0hdv said:
Worth tinkering with or does it sound like buzz saw gain much like lowering the cathode resistor from 10k to something lower can sound in an 800? I can't go any lower than 8.2k for my ears... even at that it is a little too buzzy)
Click to expand...
If you want to increase the gain in an 800s, then you need to play around with more values than just the cathode of V1B: you can go down even to 1k here, but then you need to play with the pot's (gain) value (less, solder a resistor in parallel to the pot's input and ground) and the voltage dividers - as well as the values of the coupling caps (less nFs) - and use grid stoppers in front of the CF . . . just look at some schems of higher gain amps with three stages - I'd start with the crunch of an X88R or similar.

One can get enormous amounts out of three gainstages without buzz (Diezel VH4 - ch3) . . . the post-CF MV won't be a big help btw . . .
 
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