Peavey Valve King Schematic question.

[anchovie]

The texture control looks interesting, from a quick look at the schematic that "texture" control looks to me as if its changing the balance of the phase splitter. could it be changing the symmetry of the signal ?

The way they market it is that fully anti-clockwise is the sound of a Class A amp and fully clockwise is Class AB, with the option to blend the two.

[Johan]

The texture control looks interesting, from a quick look at the schematic that "texture" control looks to me as if its changing the balance of the phase splitter. could it be changing the symmetry of the signal ?

The way they market it is that fully anti-clockwise is the sound of a Class A amp and fully clockwise is Class AB, with the option to blend the two.

they way it looks from where i stand ( with a few glases of wine ) it's a clipping symetri controll for the powertubes..most likely not very noticeble until the poweramp actually clips..probably not until the master approaches 2-3 o'clock.

[Ice-9]

Thats what i was saying Johan

[Johan]

Thats what i was saying Johan

yeah, I know. I just added that I dont think it would be noticeble until the poweramp clips. wich would for most people be very rare occations...50watt is loud...

[DougH]

My Windsor had a texture control.  It acts as a volume control for one side of the push-pull pair. As the resistance is increased, it starts sounding more "pseudo single-ended" I suppose. Very subtle but loosens the bass response and overall attack. Didn't do much for me. I removed it when I modded the amp and don't miss it. One of those things that seems like a cool idea but in practice isn't- YMMV...

For the OP, all I can say is I feel for you. Peavey has some real devilry in their relay logic. I discovered a generic factory flaw with the relay switching circuit in my Windsor, which was actually documented in the schematic too. The circuit that was supposed to bypass the fx loop was incorrect. PCB traces and the relay pin assignments were wrong. The fx loop switch basically switched the fx output to the input causing ultrasonic oscillation. I mentioned it at the Peavey forum and found out later they were doing free repairs on these at their service centers. By that time I had already voided the warranty on mine and it wasn't a big deal anyway. (I could fix it if I felt like going to the trouble but I don't use that feature anyway.) I mentioned it again a few months later and the post was clandestinely removed with no notice from a moderator or anything. No big deal but I guess the lesson for me is don't go the PV forum and tell them their "sh!t don't work"...

[Ice-9]

It's a shame that post on recall/repair was removed , i have always thought that the Peavey company founded by Hartley Peavey to be very customer friendly, I even have "The Tube Amp Book" by Hartley Peavey which was a book full of tube amp schematics, this was well before any internet was born and contains a smashing amount of original company schematics and explanations.

Ahh sorry my bad it was by Aspen Pitman of Groove Tubes not Peavey.

[DougH]

I have a lot of respect for Peavey and I think their engineering is pretty good. All companies have these sort of issues with products from time to time. Forums can be kind of strange in that they can have funny rules about what's okay and what's not, which may not be obvious. Whatever, it's not an issue for me. I just thought it was interesting how this guy is having a relay problem with his VK after what I found with the Windsor.

[served]

Some new information.

So if all the switches are disengaged I get 2.6V reading between +14 and AGND1 Measured between R212 and AGND1.
But if measuring the voltage between HTR and AGND1 I get 32V reading. This is odd. R212 is 400 ohm 5W resistor. I de and re soldered it to make sure its working. My multimeter sayd its 400 ohms. Should it lead us to somewhere?

Above mentioned Parts are on the Power Supply page.

[Johan]

Some new information.

So if all the switches are disengaged I get 2.6V reading between +14 and AGND1 Measured between R212 and AGND1.
But if measuring the voltage between HTR and AGND1 I get 32V reading. This is odd. R212 is 400 ohm 5W resistor. I de and re soldered it to make sure its working. My multimeter sayd its 400 ohms. Should it lead us to somewhere?

Above mentioned Parts are on the Power Supply page.

Hmmm... the only reference to HTR I can find on the schematics other than in the powersupply is "HTR1" below "output transformer". with that as a guide, it looks as HTR should be ~18volt to AGND2. the schematic says R212 should be 100 Ohm and not your 400 Ohm. but if we use your numbers and Ohms law.   the "supposed" 18volt minus 2.5 then divided by 400 Ohm I get~4mA ..if we had a 100 ohm resistor as stated in the schematic 0.04/100 would have given 4volts across R212 18-4=14volt...aha, numbers add up...I think someone at the Peavey plant stuffed the wrong resistor in your R212 slot...what doesnt add up is your measured 32volt at HTR to ground..on the other hand, if HTR is 18volts to AGND2 and AGND2 and AGND1 is separated by a 47 ohm resistor and different currents run through the different circuits, so I'm not supriced...I think you've found it..I think your R212 is wrong. the schematic says 100 Ohm. you measured 400..someone at the plant made a mistake....
J

[served]

Well no sadly, its just the wrong schematic

The correct one is downloadable here http://forums.peavey.com/download/file.php?id=5330&sid=4a0527e475633a1bcf5e7cf629daa418

And it says it should be 400 ohm. So this is not the problem.
So I am sorry, the schematic in the first post is wrong. I posted it because I had it and its pretty much the same just with other component values and little more.

I'll measure the voltage on C211 then I can see what is the correct voltage on HTR. Its actually weird. Why the voltage is so low, there must be something very wrong that drains it.

[served]

Could some one guess, why +14V is not 14V and is only 2.6V?
If I switch on Gain switch the voltage goes to desired level 15.1V. Something is shorting that voltage, but what could it be?

Now that shows that there is nothing wrong with - side of the relay power. Something is shorting something somewhere.

I measured resistance between Q103 and GND0 And got 22 ohms I am thinking that maybe the voltage is driving away through diodes to Q103. May be its just late and i am tired.

Another thing that I noticed. If I started the amp without the Main board connected to the chassis. It didnot make any sound. Is it supposed to be like this?