Jen Double Sound wah/fuzz - faulty construction?

Started by Halkbi, September 25, 2017, 06:15:32 AM

Previous topic - Next topic

Halkbi

Warning: first post ahead  ;)

Some time ago I aquired a vintage Jen Double Sound wah with a built-in fuzz circuit. This is the same pedal that John Wetton used in his King Crimson days and I mainly got it for the wah part (which according to my research is the same thing as the italian made Vox Crybaby). I just recentry got the sweep position right and I'm really satisfied with what the wah does. The fuzz circuit sounds cool too (which I believe is a fuzzface kind of thing), but things get weird when both the fuzz and the wah are engaged at the same time. I'm no expert in audio electronics, but to me it sounds sort of as if the clean signal is running in parallel with the fuzz signal, resulting in a noticable volume drop and a very odd and "broken" kind of sound that could suggest some phase issues. This is not how a wah and fuzz (pre or post wah) would typically sound.

Here's a shitty clip that I recorded with my phone for the sake of reference. I'm playing a four bar riff on a telecaster into an old Peavey tube amp twice per sound in the following order: clean, wah, fuzz, wah+fuzz and just wah.

https://soundcloud.com/halkbi/jen-double-sound/s-OEIqc

What do you guys think is the issue here? Like I said I'm perfectly happy with the wah on it's own, but it just bugs me that I can't use both effects on the same time and given that I don't have a fuzz right now it sure would save me some money to get it fully functioning.

Here's a schematic: http://www.franksmusic.homecall.co.uk/jen_doublesoundsuper/JDSSschem.png

Kipper4

Well In my humble opinion it sounds like I'd expect a fuzz face into a wah to sound.
I could be wrong I'm not much of a fuzz user.
It would make sense to put the fuzz before the wah. I cant see the schematic the page won't load.

There's quite a bit of ripple on the wah decay. I guess you set it like that to get the range of freqauncies you wanted from the wah.

I dunno sounds ok to me.
Ma throats as dry as an overcooked kipper.


Smoke me a Kipper. I'll be back for breakfast.

Grey Paper.
http://www.aronnelson.com/DIYFiles/up/

PRR

  • SUPPORTER

Halkbi

Quote from: Kipper4 on September 25, 2017, 12:35:19 PM
Well In my humble opinion it sounds like I'd expect a fuzz face into a wah to sound.
I could be wrong I'm not much of a fuzz user.
It would make sense to put the fuzz before the wah. I cant see the schematic the page won't load.

There's quite a bit of ripple on the wah decay. I guess you set it like that to get the range of freqauncies you wanted from the wah.

I dunno sounds ok to me.

In my personal experience fuzz pre-wah gets a lot more brutal than what I'm getting here. It's a rather harsh kind of sound. This is a good example of how it should sound: https://www.youtube.com/watch?v=BDyBQ6yIARI&feature=youtu.be&t=1m11s
Wah pre-fuzz tends to get a lot less pronounced; on extreme fuzz settings rocking your wah will barely change your sound at all which is why I prefer to put my wah after any fuzz.

To my ears it sounds almost as if only the top end is affected by the fuzz when the wah kicks in, with the bottom getting through as rather clean. It just ain't sweeping the fuzz like it should and given the fact that both effects sounds good on their own I suspect that the two effects are just oddly wired in or something. The drop in volume when both fuzz and wah are engaged at the same time is unlike anything I've ever experienced with other pedals. I've tried the wah with other fuzzes before and after it and it behaved like I would expect it to.

thermionix

I agree that it doesn't sound like any wah>fuzz or fuzz>wah that I've heard before.  No idea why.  I can't figure out what is happening with the switching setup depicted in the schematic.

That said, the wah sound is killer.  What inductor does it have?  Stack of dimes?  Somewhat unusual that two different transistors are used, if that schematic is correct.

Halkbi

Quote from: thermionix on September 26, 2017, 03:12:30 PM
I agree that it doesn't sound like any wah>fuzz or fuzz>wah that I've heard before.  No idea why.  I can't figure out what is happening with the switching setup depicted in the schematic.

That said, the wah sound is killer.  What inductor does it have?  Stack of dimes?  Somewhat unusual that two different transistors are used, if that schematic is correct.

I haven't done any reverse engineering of the pedal. It's been five years since I did anything like that so it would certainly take some time to get it all right. Would it help if I looked further into the fuzz on/off-switch and posted it here? I can't really see where else anything could be wrong.

The wah sounds great indeed. For all my life I had been using my dad's old 70's Vox Wah and I bought this because he wanted it back. Can't really blame him since it's by far the best sounding wah I've ever heard. It was very hard to identify model wise; the only clue it gave were the numbers 250.049 on the bottom lid. After some research i found that some of the Jen wahs (Jen made the Vox wahs of that era) also had the number 250 on the bottom lid. By chance I found one on a used music gear site and got it for a decent price. The sound and feel is very similar to an old Vox one, although it differs a bit Q and sweep wise. When it comes to the inductor I'm pretty sure it has a red fasel in it; however I'm not sure wether it's an old one or one of new Dunlop ones. The old Vox has a black one.

thermionix

Pictures of the guts are always nice, and maybe we can see how the switching is implemented (maybe not).

reddesert


dccable

The Fuzz and the Wah are wired in parallel on the Jen Doublesound.  That's the reason for the unique sound of that family of pedals.

tunezi

does anyone know if these units have a drop in level when the wah is engaged? i have one that i'm fixing up that was dead when I got it. I have it passing signal in both wah and fuzz mode, the overall level has a bit of a drop when i engage the wah, when the fuzz is engaged its a bit higher than the wah but still lower than the input.

timsbun

Quote from: dccable on November 26, 2017, 08:01:00 AM
The Fuzz and the Wah are wired in parallel on the Jen Doublesound.  That's the reason for the unique sound of that family of pedals.

No it is not parallel, it is series, the fuzz part first, then into the wah. I owned one of these, and am looking at the schematic right now...series.  Not a unique sound or family of pedals at all, as its basically just a fuzzface into a vox wah, thats it. Unless you got one someone repaired or modded wrong or a clone that was built wrong. The stock pedal is series, not parallel, look at the schematic by the effects master Dirk Hendrik, just a basic series fx pedal.