Wampler Paisley Drive - Gut Shot  [traced]

General documentation, gut shot, schematic links, ongoing circuit tracing, deep thoughts ... all about boutique stompboxes.

Re: Wampler Paisley Drive - Gut Shot

Postby kbibs » 25 Apr 2011, 01:34

Just wondering if anyone knows what the mystery cap (?) is? ... it appears that one end is tied to the input after a 10 or 100 ohm resistor and I'm guessing the other end is tied to ground forming a low pass filter. I'm surprised it's a film cap cause usually the values are 100 to 220 pf. Any ideas?
kbibs
 
Posts: 30
Joined: 31 Jul 2008, 18:07
Has thanked: 3 times
Have thanks: 1 time

Re: Wampler Paisley Drive - Gut Shot

Postby kbibs » 25 Apr 2011, 12:56

Nevermind! ... I didn't realize Wima made polypropelene film caps in the pf range. So its probably a 100pf cap as I expected it to be.
kbibs
 
Posts: 30
Joined: 31 Jul 2008, 18:07
Has thanked: 3 times
Have thanks: 1 time

Re: Wampler Paisley Drive - Gut Shot

Postby MoonWatcher » 25 Apr 2011, 20:15

kbibs wrote:Nevermind! ... I didn't realize Wima made polypropelene film caps in the pf range. So its probably a 100pf cap as I expected it to be.


No - the little TS 51pF "bleeder cap" is the standard ceramic disk.

Brian mentioned that it's getting harder to find the Panasonic caps. As such, everyone seems to be on the hunt for other manufacturers of the metalized film caps. You will probably see pedals from all sorts of builders that will have a mix of different cap brands until they settle on a supplier that has everything they need in the right quantities. I bought a boatload of AVX caps before they were discontinued, and am only starting to run out of them now (if I built a zillion pedals like Wampler, they'd have been gone a long time ago). So new builds of mine are mixed with AVX's/Panasonics/Wima/Vishay Roderstein/etc./etc. That "rogue cap" is probably just a 1uF cap on the output of a buffer or the op amp.
MoonWatcher
Diode Debunker
 
Posts: 718
Joined: 28 Jul 2008, 13:27
Has thanked: 42 times
Have thanks: 63 times

Re: Wampler Paisley Drive - Gut Shot

Postby kbibs » 26 Apr 2011, 01:54

Thanks for your response MoonWatcher! The mystery cap I was talking about is the red one (Wima) with the ? on it in the gut shot. If I followed the traces correctly the input goes through a series 100ohm resistor then the 1M resistor goes to ground and then the red cap in question goes to ground I believe in parallel to the 1M resistor. From there it goes into the normal TS 0.022 input cap. That red film cap in parallel to the 1M resistor is what I was surprised about. I expected a ceramic or silver mica cap in the 100pf range to be there. Then I looked up Wima polypropelyne film caps and sure enough they make them down to 33pf and the physical dimensions look about right. So I think Brian just added a little more filtering (I think in the 16khz range) to the input with this cap.

I have the circuit on a breadboard now and it is a very nice sounding OD, very versatile too. Kudos to Brian! Now I'm not sure whether to do the whole thing on perfboard or order a TS board from GGG or BYOC and just do the tone switching components on perf. I'll have to make sure I plug in the JFETs to the board correctly too.
kbibs
 
Posts: 30
Joined: 31 Jul 2008, 18:07
Has thanked: 3 times
Have thanks: 1 time

Re: Wampler Paisley Drive - Gut Shot

Postby Victor Nery » 12 Apr 2012, 13:44

Greetings,

Does anyone have a final schematic?

Thanks
Victor Nery
 
Posts: 45
Joined: 18 Nov 2011, 04:29
Has thanked: 29 times
Have thanks: 2 times

Re: Wampler Paisley Drive - Gut Shot  [traced]

Postby hbo » 05 May 2012, 00:38

I'm doing a re-housing on this one for a friend so I thought I'd trace the circuit to the best of my ability while at it, seeing that we haven't got a complete schematic for this one yet.
You do not have the required permissions to view the files attached to this post.

For this message the author hbo has received thanks: 13
agung (05 May 2012, 03:42), chi_boy (23 Nov 2012, 02:36), Groovenut (05 May 2012, 02:02), IvIark (05 May 2012, 01:08), J0K3RX (20 Apr 2014, 02:16), jrod (27 Dec 2012, 15:30), jstbrowsin (05 May 2012, 04:35), lukatosh (05 May 2012, 03:34), Manfred (08 May 2012, 21:04), oh7hhi (13 Jul 2012, 14:04) and 3 more users
hbo
Breadboard Brother
 
Posts: 101
Joined: 10 Apr 2009, 17:46
Location: Oslo, Norway
Has thanked: 31 times
Have thanks: 207 times

Re: Wampler Paisley Drive - Gut Shot

Postby lukatosh » 05 May 2012, 03:35

D3 its a polarity protection diode... 1N400x should work fine!

what else is missing?
lukatosh
Solder Soldier
 
Posts: 192
Joined: 04 Dec 2010, 03:55
Has thanked: 33 times
Have thanks: 180 times

Re: Wampler Paisley Drive - Gut Shot

Postby HHR18 » 08 May 2012, 10:42

I think nothing else is missing, a vero layout would be greatly appreciated!
User avatar
HHR18
 
Posts: 49
Joined: 14 Jan 2012, 01:59
Has thanked: 18 times
Have thanks: 3 times

Re: Wampler Paisley Drive - Gut Shot

Postby MullisMan » 24 May 2012, 18:45

What is the use for the two biasing networks?
I want to build it all.
MullisMan
Breadboard Brother
 
Posts: 128
Joined: 23 Feb 2010, 06:22
Location: NC
Has thanked: 13 times
Have thanks: 53 times

Re: Wampler Paisley Drive - Gut Shot

Postby chi_boy » 27 Dec 2012, 03:52

hbo wrote:I'm doing a re-housing on this one for a friend so I thought I'd trace the circuit to the best of my ability while at it, seeing that we haven't got a complete schematic for this one yet.



In regards to the biasing networks, is there a reason for using 3 220uF caps as opposed to 1 220uf and 2 100uF? Customarily one sees a large cap on the main line and a smaller (half the main line value) cap on the bias network.

I know there is nothing "wrong" with it, but I'm just curious if there is a technical motivation.

Cheers,
George
chi_boy
 
Posts: 32
Joined: 07 Jun 2010, 03:54
Has thanked: 26 times
Have thanks: 13 times

Re: Wampler Paisley Drive - Gut Shot

Postby marco.r68 » 13 Feb 2013, 15:33

It's a Tube screamer! Shit!
marco.r68
 
Posts: 1
Joined: 17 Jan 2013, 15:42
Has thanked: 0 time
Have thanks: 0 time

Re: Wampler Paisley Drive - Gut Shot

Postby ppluis0 » 13 Feb 2013, 16:26

Hey guys:

It´s there an advantage to have a pair of voltage dividers (R22, R23, C13 and R24, R25, C14), instead a single one ?

Sorry to redo the same question about this matter. I think that is sufficient with one divider, but who knows...

Cheers,
Jose
User avatar
ppluis0
Cap Cooler
 
Posts: 535
Joined: 14 Jul 2010, 19:33
Location: Argentina
Has thanked: 35 times
Have thanks: 72 times

Re: Wampler Paisley Drive - Gut Shot

Postby IvIark » 13 Feb 2013, 16:46

Yes I only used one divider in my layout, it works fine and is quiet so I don't know what advantage two separate networks would give you.
"If anyone is a 'genius' for putting jacks in such a pedal in the only spot where they could physically fit, then I assume I too am a genius for correctly inserting my legs into my pants this morning." - candletears7 - TGP

For this message the author IvIark has received thanks:
ppluis0 (14 Feb 2013, 01:05)
User avatar
IvIark
Tube Twister
 
Posts: 2297
Joined: 02 Jan 2008, 00:59
Location: Manchester UK
Has thanked: 667 times
Have thanks: 678 times

Re: Wampler Paisley Drive - Gut Shot

Postby MoonWatcher » 13 Feb 2013, 17:10

IvIark wrote:Yes I only used one divider in my layout, it works fine and it quiet so I don't know what advantage two separate networks would give you.


Only thing I could imagine would be if this pcb were re-used for some higher gain design? A Tubescreamer just doesn't seem to have the gain to be noisy.

I've noticed a little bit of a higher noise floor if doing the 2X gain thing with the 2k2/100nF trick with an actual Tubescreamer, so maybe it's to offset that - this one uses 2k2/220nF.

It almost looks like this is carried over from something like the Pinnacle, since you see a separate bias network for each mu amp/minibooster-derived stage.

There also seems to be a higher than usual incidence of complaints from users of mu amp module-based amp simulators like the Dirty Little Secret, especially if they are using a 18VDC source. If you're going for a specialized pedal, something like hum could be a real problem in the eyes of the user - don't need a potential rep for that. So the biasing/filtering might be overkill, or just a decent little insurance policy. Easy enough to include when the pcb is being laid out, right? Just make it sort of consistent for the entire line, whether all of them benefit from it or not.

But for our purposes, yeah - not necessary to have more than one network. At least for an OD like this.

For this message the author MoonWatcher has received thanks:
ppluis0 (14 Feb 2013, 01:05)
MoonWatcher
Diode Debunker
 
Posts: 718
Joined: 28 Jul 2008, 13:27
Has thanked: 42 times
Have thanks: 63 times

Re: Wampler Paisley Drive - Gut Shot

Postby ppluis0 » 14 Feb 2013, 01:05

Thank you guys for your comment.

220uF to decouple the divider network seems overkill and enough (at least enough to me) to assure a clean reference point in this kind of OD units.

Perhaps use several Vcc/2 networks make more sense to isolate noisy stages like VCO`s, clock sections in delays, and so on from the analog section in more complex units. I think.

Cheers,
Jose
User avatar
ppluis0
Cap Cooler
 
Posts: 535
Joined: 14 Jul 2010, 19:33
Location: Argentina
Has thanked: 35 times
Have thanks: 72 times

Re: Wampler Paisley Drive - Gut Shot

Postby tiagojoy » 01 Feb 2014, 03:36

Hi!

I made a layout for this pedal has not been tested!

Any error let me know!


:horsey: :horsey: :horsey: :horsey:
You do not have the required permissions to view the files attached to this post.

For this message the author tiagojoy has received thanks: 3
bluesaxe (01 Feb 2014, 11:15), cdeschenes (01 Feb 2014, 08:35), Manfred (01 Feb 2014, 15:52)
tiagojoy
 
Posts: 17
Joined: 21 May 2010, 01:21
Has thanked: 0 time
Have thanks: 11 times

Re: Wampler Paisley Drive - Gut Shot

Postby jhergonz » 03 Sep 2018, 06:18

I'm curious about the mid contour switch, is it really DPDT(on-on-on) switch? or DPDT(on-off-on)? I think it is impossible to disconnect both C7 and C6 to ground at the same time if it is on-on-on, instead, both will be connected.
jhergonz
 
Posts: 22
Joined: 29 Mar 2018, 07:28
Location: Philippines
Has thanked: 40 times
Have thanks: 0 time

Previous

Return to Boutique Stompboxes dissected...

Who is online

Users browsing this forum: george giblet and 7 guests