Wampler - Velvet Fuzz  [traced]

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Ripdivot
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Post by Ripdivot »

Ripdivot wrote:
Ripdivot wrote:
Ripdivot wrote:Well I decided to breadboard this bad boy today. I don't have an LM386 in stock so I decided to play with the 2n5089 circuit to try and make it do the "big" and "tight" settings. Obviously I don't have the original tight circuit to compare to but I still managed acceptable results.

First off I found that if the circuit is in "big" mode (stock 2n5089 circuit) and you back the fuzz off a bit there isn't enough high end so I switched the 100pf bleed cap on the fuzz control to 220pf like on the original PlexiDrive gain control and it did the job.

For the "tight" setting I tried various i/p caps, o/p caps and emitter bypass caps. I found all that was necessary was to switch the 47uf emitter bypass cap to a .47uf and it tightened right up.

I'm looking forward to getting an LM386 to compare to. I might just leave it as is because it works well and is nice and simple the way I have it now. By the way I have never built the PlexiDrive prior to today and I think it sounds great by itself as well!
Just occured to me that if you switch the 4n7 low pass filter cap on the output of the 2n5089 circuit to 33n at the same time you switch the other cap I decribed when switching to tight the low pass frequency will be the same as the LM386 circuit (482Hz).
OK I can confirm that switching both caps works great, sounds very much like the demos. I will still get an LM386 to compare but I'm really liking this! :thumbsup
Here is a redraw of the schematic showing my changes. I've played through the circuit for many hours and it sounds great.
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WVFv10 mods.jpg

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crw414tele
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Post by crw414tele »

I've done some more experimenting with the boost only circuit and have now wired it with a bypass switch and can confirm there was no volume drop , as I has no bypass before I couldn't tell how loud it was compared to when it was off so when stacked with another pedal the volume drop perceived was the stacked circuit acting as a limiter, now the boost is quite loud on it's own.I also replaced the 1k output resistor with a 100kA pot as a master volume but that had 90% in the first 1/2 turn , so I've got a 1ook linear now and that works better, a reverse log might be better still but I don't have one at the moment.
This circuit stacks awesome , I am really liking it into my boiling point maybe even more than the plexi drive.I also tried it into an ecstasy and black 65 and they also work really well. I am definitely boxing this with the plexi but will make it independently switchable so I can use it with whatever pedal I choose.

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Post by jallenshaw »

Ok....my layout is also verified!

Review:
The pedal does what it's advertised to do.....fuzz into a cranked amp tone

The Tight side works great with my ES339 in all pickup positions, and also sounds good with the Tele and Strat, so humbuckers and single coils are good with that section.

The Fat (Big) side is a bit much (big and mooshy) for my taste with the humbuckers, although in the bridge position it sounds quite good.
Where that section really shines is with the single coils! Really fattens them up for that EJ type tone.

Running it thru my "Dumblized" Twin Reverb, the pedal sounds "OK" with the clean channel, but really sings when used with the OD channel.

So, while not a "leave it on all the time" pedal for me, it definitely will get lots of use, especially when the volume has to be kept low in certain venues.

JAS

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Post by Philster »

I ended up making small vero's of each boost circuit - they each sound good going into a Plexi drive but also into a Zendrive. Not so impressive into a TS. :lol:
It's funny because they are not particularly fuzzy on their own (and I was expecting them to be fuzzes!) but into the Plexi they give that "Fuzzface into a cranked amp" sound (i.e. all the nasty fuzz overtones smoothed out with more saturation that a fuzz into a clean amp). But each circuit does have a different character. I aim to make the switchable caps mod to the fat circuit next.
Cheers
Philly
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fat.gif (14.24 KiB) Viewed 3466 times
386.gif

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jallenshaw
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Post by jallenshaw »

Here's a couple mods that made the pedal perfect to my ears.

1) Even with the tone all the way up the pedal was too dark, so I replaced the 25k tone pot with a 50k. Now I have much better control over the brightness....perfection

2) The 2N5089 was simply too hot for me, so I subbed in (and re-biased by ear) my old standby favorite trannie....a 2SK170BL
WOW! Now the Fat/Big side is totally usable with all my guitars, and it has a sweet "vowel" type tone.

This pedal was well worth all the effort and waiting!

A very big THANKS to all who contributed with tracings and layouts!

here's a few final pictures......

JAS
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Fuss tight top.JPG
Fuss fat top.JPG
Fuss final gut.JPG

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Ripdivot
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Post by Ripdivot »

Ripdivot wrote:
Ripdivot wrote:
Ripdivot wrote:
Ripdivot wrote:Well I decided to breadboard this bad boy today. I don't have an LM386 in stock so I decided to play with the 2n5089 circuit to try and make it do the "big" and "tight" settings. Obviously I don't have the original tight circuit to compare to but I still managed acceptable results.

First off I found that if the circuit is in "big" mode (stock 2n5089 circuit) and you back the fuzz off a bit there isn't enough high end so I switched the 100pf bleed cap on the fuzz control to 220pf like on the original PlexiDrive gain control and it did the job.

For the "tight" setting I tried various i/p caps, o/p caps and emitter bypass caps. I found all that was necessary was to switch the 47uf emitter bypass cap to a .47uf and it tightened right up.

I'm looking forward to getting an LM386 to compare to. I might just leave it as is because it works well and is nice and simple the way I have it now. By the way I have never built the PlexiDrive prior to today and I think it sounds great by itself as well!
Just ocured to me that if you switch the 4n7 low pass filter cap on the output of the 2n5089 circuit to 33n at the same time you switch the other cap I described when switching to tight the low pass frequency will be the same as the LM386 circuit (482Hz).
OK I can confirm that switching both caps works great, sounds very much like the demos. I will still get an LM386 to compare but I'm really liking this! :thumbsup
I wired up the LM386 tonight. I have to say I like it better than the switchable caps mod I came up with for the 5089 boost. I agree with jallenshaw that the 50K tone pot helps open it up a bit if you need that little bit of extra high end. I left the treble bleed cap on the gain control at 220pf instead of 100pf. This allows for a little more high end when you turn the gain down. I'll try a lower gain transistor tomorrow in place of the 5089 and report back.

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Post by crw414tele »

I'm actually preferring the tight side myself at the moment , I tried a bc550c today but didn't like it , gone back to the mpsa18 which sounds huge. I just run the fat side with the level down a bit past the stock setting and it is still big but not too woolly. This pedal really works for single coils, but the tight side into my black 65 get an awesome smooth fuzz rhythm tone with my humbucker tele

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Post by Ripdivot »

One thing I've noticed is that my circuit cleans up when I roll the guitar vol pot down but not as good as in demos I've heard. Certainly doesn't have the clean-up that my fuzz face has. I find I have to roll the my guitar volume almost all the way down to get clean-up if the gain is cranked on the VF.

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Post by Nocentelli »

Ripdivot wrote:I find I have to roll the my guitar volume almost all the way down to get clean-up if the gain is cranked on the VF.
Humbuckers or single coils? The clean-up seems much better with single coils (often the case with fuzz circuits, even the venerated fuzzface).
modman wrote: Let's hope it's not a hit, because soldering up the same pedal everyday, is a sad life. It's that same ole devilish double bind again...

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Post by Ripdivot »

Nocentelli wrote:
Ripdivot wrote:I find I have to roll the my guitar volume almost all the way down to get clean-up if the gain is cranked on the VF.
Humbuckers or single coils? The clean-up seems much better with single coils (often the case with fuzz circuits, even the venerated fuzzface).
I've been testing it with singles in a strat.

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Post by andregarcia57 »

Ripdivot wrote:
Ripdivot wrote:
Ripdivot wrote:
Ripdivot wrote:Well I decided to breadboard this bad boy today. I don't have an LM386 in stock so I decided to play with the 2n5089 circuit to try and make it do the "big" and "tight" settings. Obviously I don't have the original tight circuit to compare to but I still managed acceptable results.

First off I found that if the circuit is in "big" mode (stock 2n5089 circuit) and you back the fuzz off a bit there isn't enough high end so I switched the 100pf bleed cap on the fuzz control to 220pf like on the original PlexiDrive gain control and it did the job.

For the "tight" setting I tried various i/p caps, o/p caps and emitter bypass caps. I found all that was necessary was to switch the 47uf emitter bypass cap to a .47uf and it tightened right up.

I'm looking forward to getting an LM386 to compare to. I might just leave it as is because it works well and is nice and simple the way I have it now. By the way I have never built the PlexiDrive prior to today and I think it sounds great by itself as well!
Just occured to me that if you switch the 4n7 low pass filter cap on the output of the 2n5089 circuit to 33n at the same time you switch the other cap I decribed when switching to tight the low pass frequency will be the same as the LM386 circuit (482Hz).
OK I can confirm that switching both caps works great, sounds very much like the demos. I will still get an LM386 to compare but I'm really liking this! :thumbsup
Here is a redraw of the schematic showing my changes. I've played through the circuit for many hours and it sounds great.

it is necessary to regulate the 4.5V transistors Q2 (R18), Q3 (21) and Q4 (R25)?

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Post by Ripdivot »

andregarcia57 wrote:
Ripdivot wrote:
Ripdivot wrote:
Ripdivot wrote:
Ripdivot wrote:Well I decided to breadboard this bad boy today. I don't have an LM386 in stock so I decided to play with the 2n5089 circuit to try and make it do the "big" and "tight" settings. Obviously I don't have the original tight circuit to compare to but I still managed acceptable results.

First off I found that if the circuit is in "big" mode (stock 2n5089 circuit) and you back the fuzz off a bit there isn't enough high end so I switched the 100pf bleed cap on the fuzz control to 220pf like on the original PlexiDrive gain control and it did the job.

For the "tight" setting I tried various i/p caps, o/p caps and emitter bypass caps. I found all that was necessary was to switch the 47uf emitter bypass cap to a .47uf and it tightened right up.

I'm looking forward to getting an LM386 to compare to. I might just leave it as is because it works well and is nice and simple the way I have it now. By the way I have never built the PlexiDrive prior to today and I think it sounds great by itself as well!
Just occured to me that if you switch the 4n7 low pass filter cap on the output of the 2n5089 circuit to 33n at the same time you switch the other cap I decribed when switching to tight the low pass frequency will be the same as the LM386 circuit (482Hz).
OK I can confirm that switching both caps works great, sounds very much like the demos. I will still get an LM386 to compare but I'm really liking this! :thumbsup
Here is a redraw of the schematic showing my changes. I've played through the circuit for many hours and it sounds great.

it is necessary to regulate the 4.5V transistors Q2 (R18), Q3 (21) and Q4 (R25)?
Yes the fets should be as close to 4.5 volts as possible to get a proper sounding clone. Mine are between 4.4v and 4.8v.

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Post by andregarcia57 »

Ripdivot wrote:
andregarcia57 wrote:
Ripdivot wrote:
Ripdivot wrote:
Ripdivot wrote:
Ripdivot wrote:Well I decided to breadboard this bad boy today. I don't have an LM386 in stock so I decided to play with the 2n5089 circuit to try and make it do the "big" and "tight" settings. Obviously I don't have the original tight circuit to compare to but I still managed acceptable results.

First off I found that if the circuit is in "big" mode (stock 2n5089 circuit) and you back the fuzz off a bit there isn't enough high end so I switched the 100pf bleed cap on the fuzz control to 220pf like on the original PlexiDrive gain control and it did the job.

For the "tight" setting I tried various i/p caps, o/p caps and emitter bypass caps. I found all that was necessary was to switch the 47uf emitter bypass cap to a .47uf and it tightened right up.

I'm looking forward to getting an LM386 to compare to. I might just leave it as is because it works well and is nice and simple the way I have it now. By the way I have never built the PlexiDrive prior to today and I think it sounds great by itself as well!
Just occured to me that if you switch the 4n7 low pass filter cap on the output of the 2n5089 circuit to 33n at the same time you switch the other cap I decribed when switching to tight the low pass frequency will be the same as the LM386 circuit (482Hz).
OK I can confirm that switching both caps works great, sounds very much like the demos. I will still get an LM386 to compare but I'm really liking this! :thumbsup
Here is a redraw of the schematic showing my changes. I've played through the circuit for many hours and it sounds great.

it is necessary to regulate the 4.5V transistors Q2 (R18), Q3 (21) and Q4 (R25)?
Yes the fets should be as close to 4.5 volts as possible to get a proper sounding clone. Mine are between 4.4v and 4.8v.


did you fit or found a trio of J201 without touching the resistors?
where has bought the J201?
thanks

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Post by Ripdivot »

I sorted through about 50 that I had on hand and found only about 4 that were in the correct range. I tried several that were out of range and adjusted the drain resistors to get the voltage to about 4.5v and they all sounded just fine. Not sure where I bought the j201's, I've had them for years. I think I got them from Mouser but not 100% sure.

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Post by andregarcia57 »

Ripdivot wrote:I sorted through about 50 that I had on hand and found only about 4 that were in the correct range. I tried several that were out of range and adjusted the drain resistors to get the voltage to about 4.5v and they all sounded just fine. Not sure where I bought the j201's, I've had them for years. I think I got them from Mouser but not 100% sure.

I have also found MMBFJ201, would give to be used in the project?

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Post by Nocentelli »

I don't see why not, it may well be just a different package (smd?). I'm going to try it with some 2N5457s when I have some time.
modman wrote: Let's hope it's not a hit, because soldering up the same pedal everyday, is a sad life. It's that same ole devilish double bind again...

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Post by mganzer »

For shure I will try other amp simulator... Something like srpp. For shure less trouble for good tone...

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Post by indyguitarist »

quick note. At a glance, tone control is wrong. Also, sort through all jfets, 5089's, and 386's to make sure you are using low noise parts, you'll find tolerance can be a bit varied and it's crucial in a circuit such as this unless you don't want consistency.

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Post by jallenshaw »

Brian, thanks for the tip on the tone control.

However, even if not correct (to the original) it works great in my unit. I absolutely LOVE this circuit...now my favorite, replacing the Fetto as #1

Also, the drive pots (replacing the fixed voltage dividers feeding the plexi-drive) are essential to me to get a wide range of great tones out of this thing.

Thanks for such a terrific design!

JAS

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Post by Ripdivot »

indyguitarist wrote:quick note. At a glance, tone control is wrong.
I've looked over the photos a few times and the trace looks correct to me but it's possible the cap value is wrong?

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