Diezel VH4 Pedal  [schematic]

All about modern commercial stompbox circuits from Electro Harmonix over MXR, Boss and Ibanez into the nineties.
SoftPalate
Information
Posts: 6
Joined: 17 May 2019, 17:17
Has thanked: 4 times

Post by SoftPalate »

Hey guys,

I'm new to all of this stuff and I recently picked up one of these boards and populated it and am ready to install it. I'm using a 1590BB (which is, I believe, what it was designed for) and after I got all the holes drilled I discovered that, while the pots all fit nicely, there isn't any room "beneath" them for the jacks to fit. All of your build pics look so nice and neat and I can't even find a way to squeeze those jacks in the enclosure. Am I doing something wrong?

Thanks for any help... :roll:

caspercody
Resistor Ronker
Information
Posts: 336
Joined: 15 Jul 2009, 14:34
Has thanked: 29 times
Been thanked: 49 times

Post by caspercody »


SoftPalate
Information
Posts: 6
Joined: 17 May 2019, 17:17
Has thanked: 4 times

Post by SoftPalate »

OK, thanks. This documentation is for a different board (Valhalla), which I realize is the same kind of clone, but I was referring to the drill template I found for the Wiezel, because that's the board I was building. That one has the pots so near the top, that the jacks won't fit without sticking out below the floor of the enclosure.

I'll make an adjustment and try to drill a new enclosure.

syamilaliff
Information
Posts: 11
Joined: 19 May 2018, 13:26

Post by syamilaliff »

Putting it after a buffered did the trick. No more whistling noise.

Daverem
Information
Posts: 3
Joined: 09 Dec 2012, 19:12
Has thanked: 2 times
Been thanked: 1 time

Post by Daverem »

I built one without the charge pump to test other voltages. Is it worth raising the voltage to + -15V?

lead2203
Breadboard Brother
Information
Posts: 82
Joined: 02 May 2009, 02:09
Has thanked: 1 time
Been thanked: 10 times

Post by lead2203 »

Optical wrote:Sorry for all the posts :o

I checked the photo and the tone stack does appear to be wired Fender style. So the schematic is correct.
I wonder why they went that way instead of like the real amp... I think i'll try the other configuration anyway to see how it sounds
I don't know if someone has pointed this out yet but the tone stack in the real VH4 IS wired Fender style. Peter does it this way in most of his amps and the mods I've seen.

befey
Information
Posts: 1
Joined: 01 Jul 2019, 18:50

Post by befey »

I just finished building the pedal pcb Valhalla.

I used shielded wire on the input and output. Was getting some squealing on the highest gain settings before I put it in the enclosure.

Once it was boxed, it's super quiet even maxed.

Daverem
Information
Posts: 3
Joined: 09 Dec 2012, 19:12
Has thanked: 2 times
Been thanked: 1 time

Post by Daverem »

some experiments.....i tried with 18+-, no oscillation with to much headroom and the tone feel was not like the original, 15+- feel good,but oscillation at 3 o clock, i came back to 12v be cause is a better tone for me.

I jump the buffer stage, take off 100k and it had 0 oscillation finally, the gain looked similar to the original but with a lilttle of lost of bite tones, not to much as put a clon buffer in front
(really bad sound), the buffer in the original give there some of personality and bite, but can jump it.

Im not and expert but my theory is: the buffer with the first high gain in the same op amp maybe create the oscillation in contact with 4th stage of tone control treble section....maybe some day i gonna build one with a insolated buffer and first stage, but without the buffer stage sound really good to me...

Daverem
Information
Posts: 3
Joined: 09 Dec 2012, 19:12
Has thanked: 2 times
Been thanked: 1 time

Post by Daverem »

I finally build the same buffer in a insolated pcb and i canceled the original in the op amp... The oscillation is gone!!! And the tone is same as the original....maybe there was the problem, too much gain inside the same op amp... Now I gonna redesing the pcb, change all tl072 by opa2130 or jrc4580 for tube screamer flavor and return to the Icl7660 .... By the way, i took off the Insolated wires and still without oscillation, but with a little of ground noise, I gonna return at them for a better quiet tone...

freshmex18
Information
Posts: 2
Joined: 20 Feb 2020, 07:03

Post by freshmex18 »

I just built this and I am having troubles. The pedal does not work at all when it is switched on. All I get is a high pitched whine even though I used shielded wire for the input and the gain. When the pedal is off, the gain knob somehow affects the bypass signal. When the gain knob is turned all the way down, the bypass works; if I turn it up, the signal disappears and is replaced with a whine/beeping sound. I have checked every component and they are all in the right place and oriented correctly. I have resoldered every connection twice. Anyone have any ideas?

freshmex18
Information
Posts: 2
Joined: 20 Feb 2020, 07:03

Post by freshmex18 »

OK, I was wrong. One of the 2.2 electrolytic caps was off by one hole. Now that that's fixed and everything is verified in the correct place and resoldered, nothing works at all. No signal going through to the amp either when the pedal is on or off. I'm at a loss.

Does anyone have a pic of the offboard wiring? Wondering if I did something wrong there

dfx_pcbs
Information
Posts: 7
Joined: 16 Feb 2018, 18:12

Post by dfx_pcbs »

befey wrote:I just finished building the pedal pcb Valhalla.

I used shielded wire on the input and output. Was getting some squealing on the highest gain settings before I put it in the enclosure.

Once it was boxed, it's super quiet even maxed.
Just built the Valhalla, works but same as you some high pitch whine with full gain, maybe it will quieten once boxed up!

Post Reply