Mellowtone - Wolf Computer  [traced]

General documentation, gut shot, schematic links, ongoing circuit tracing, deep thoughts ... all about boutique stompboxes.
User avatar
earthtonesaudio
Transistor Tuner
Information
Posts: 1244
Joined: 28 Jan 2008, 04:00
Completed builds: Metal Simplex, Fuzz Factory, two Fab Echos-modded, Noisy Cricket, Earth & Space Wah, TS-7-modded, passive xover/splitter box, opamp fuzz
Location: Bloomington, Indiana
Has thanked: 11 times
Been thanked: 75 times

Post by earthtonesaudio »

I would suggest adding a limiting resistor (~1000 ohms) in series with the Bias pot; currently if both the Bias and the Sag controls are set to minimum resistance, then Q2 is in danger.
rocklander wrote:hairsplitting and semantics aren't exactly the same thing though.. we may need two contests for that.

User avatar
IvIark
Tube Twister
Information
Posts: 2235
Joined: 01 Jan 2008, 23:59
Location: Manchester UK
Has thanked: 562 times
Been thanked: 586 times
Contact:

Post by IvIark »

I've updated the vero so the Sag and Fuzz controls are reversed, and I also reversed the bias pot which must also be backwards if the Sag pot was.
If you CTRL + F5 to refresh and update your cache the new one should be there.
"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

User avatar
mustang
Breadboard Brother
Information
Posts: 57
Joined: 15 Feb 2010, 01:00
Location: England
Has thanked: 2 times
Been thanked: 2 times

Post by mustang »

I've just started building one of these on my blog..

http://melxfx.blogspot.com/2010/12/diy- ... t-one.html

Thanks to IvIark, CJ and everyone else who helped with the layout/figuring out stuff. :hug:

User avatar
IvIark
Tube Twister
Information
Posts: 2235
Joined: 01 Jan 2008, 23:59
Location: Manchester UK
Has thanked: 562 times
Been thanked: 586 times
Contact:

Post by IvIark »

Nice one Si. God I hope it works now you've done a new thread for it! :shock: :mrgreen:
"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

User avatar
mustang
Breadboard Brother
Information
Posts: 57
Joined: 15 Feb 2010, 01:00
Location: England
Has thanked: 2 times
Been thanked: 2 times

Post by mustang »

IvIark wrote:Nice one Si. God I hope it works now you've done a new thread for it! :shock: :mrgreen:
It will work, I have faith!! [smilie=pope.gif]

User avatar
roseblood11
Tube Twister
Information
Posts: 1887
Joined: 23 Aug 2008, 14:21
Has thanked: 366 times
Been thanked: 313 times

Post by roseblood11 »

earthtonesaudio wrote:I would suggest adding a limiting resistor (~1000 ohms) in series with the Bias pot; currently if both the Bias and the Sag controls are set to minimum resistance, then Q2 is in danger.

+1 !!!

User avatar
dkirby1
Information
Posts: 7
Joined: 01 Dec 2010, 07:53
Location: Michigan

Post by dkirby1 »

Hello, I'm new to the forum and pedal building, and I have a newb question about earthtonesaudio's post. When he suggested adding a limiting resister in series with the bias pot, and as IvIark's layout as reference, does this mean putting a resistor between the yellow wire and the third lug of the bias pot?

User avatar
IvIark
Tube Twister
Information
Posts: 2235
Joined: 01 Jan 2008, 23:59
Location: Manchester UK
Has thanked: 562 times
Been thanked: 586 times
Contact:

Post by IvIark »

Just take the yellow wire to the top row, move the right hand link one space to the right to the very edge, and put a 1K resistor from the hole to the right hand side of the top row track cut, to the third row from the bottom where the yellow wire currently goes.
"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

User avatar
dbeeson
Information
Posts: 7
Joined: 08 Dec 2010, 15:58
Has thanked: 1 time

Post by dbeeson »

I've made a PCB layout for this circuit but I can't seem to get it working. I've tried twice. Could someone have a look and see if I messed up somewhere? As far as I can see, everything is where it should be. The pot layout is the same as IvIark. There is no 1k limiting resistor on this one.
Image

User avatar
dbeeson
Information
Posts: 7
Joined: 08 Dec 2010, 15:58
Has thanked: 1 time

Post by dbeeson »

the layout without the values.
Image

User avatar
LaceSensor
Cap Cooler
Information
Posts: 585
Joined: 02 Jan 2011, 12:01
Has thanked: 57 times
Been thanked: 277 times

Post by LaceSensor »

HI

I would not bother to make this as the layout proposed in the thread doesnt make the Wolf Computer sounds.
Until someone posts gut shot with traces we cant make this properly.
The proposed schematic, when made, produces and overdrive pedal pretty much.

No negative intended I appreciate the efforts, but its not the same as a WC in sounds, so best to wait til a better version is drafted.

User avatar
dbeeson
Information
Posts: 7
Joined: 08 Dec 2010, 15:58
Has thanked: 1 time

Post by dbeeson »

Thanks for the reply.

I have built circuit already with IvIark's layout and it does sound very similar to the WC. I would not say the result is an overdrive, but I certainly agree that it is not the same as a WC, from what I've seen on the youtube videos. It is still a great effect with the starve and bias functions. I thought it would be nice to mount the switch onto the PCB, but it doesn't seem to work properly. I get a low volume when I crank the output knob, and the other knobs either seem to boost or cut the volume a bit. The overall tone is muddy as well.

User avatar
NetStar
Information
Posts: 14
Joined: 14 Apr 2009, 06:48
Been thanked: 2 times

Post by NetStar »

I've spoken to Melx and will see if I can borrow my friend's Wolf Computer to be sent to him/IVIark for investigation.
In the meantime, please don't waste you time with previous layouts.

User avatar
LaceSensor
Cap Cooler
Information
Posts: 585
Joined: 02 Jan 2011, 12:01
Has thanked: 57 times
Been thanked: 277 times

Post by LaceSensor »

@Netstar, that would be awesome, thanks for your efforts.

The layout listed, while cool in its own right, isnt a WC sadly.
IF someone can do trace shots in detail perhaps we can figure this one out.

Cheers all

User avatar
IvIark
Tube Twister
Information
Posts: 2235
Joined: 01 Jan 2008, 23:59
Location: Manchester UK
Has thanked: 562 times
Been thanked: 586 times
Contact:

Post by IvIark »

Thanks NetStar, you're an ... erm star! :mrgreen:
"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

User avatar
NetStar
Information
Posts: 14
Joined: 14 Apr 2009, 06:48
Been thanked: 2 times

Post by NetStar »

I might be able to take pictures when I get it. I'll borrow my flatmate's camera.

User avatar
IvIark
Tube Twister
Information
Posts: 2235
Joined: 01 Jan 2008, 23:59
Location: Manchester UK
Has thanked: 562 times
Been thanked: 586 times
Contact:

Post by IvIark »

That would be great, if you could get a decent front and back board pic then you won't need to send it out. :thumbsup
"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

User avatar
jchot
Information
Posts: 3
Joined: 09 Jul 2013, 14:59
Has thanked: 2 times
Been thanked: 1 time

Post by jchot »

uh... guys?

I know I'm a little late to the party, but i just bread-boarded this and it sounds just like a wolf computer:
http://forum.gtlab.net/cgi-bin/yabb2/Ya ... 7545538/20
Image

User avatar
Beedoola
Resistor Ronker
Information
Posts: 383
Joined: 01 Feb 2008, 22:52
Location: Bay Area, CA
Has thanked: 15 times
Been thanked: 32 times

Post by Beedoola »

Hi there. I borrowed a friend's original a made a clone for myself years ago and then sold the clone to my roommate - not knowing there was issues with the schematics out there. I had just popped open the original and eyeballed the layout and made one matching it.

My old roommate let me borrow the clone so I could check it out. Here is the schem as matching the clone I made.

The parts used were taken from when Mellowtone shared the parts info in the previous pages. I can't be for sure if I matched those values with what was in the actual WCPU I borrowed, but I think it sounds the same...
Attachments
Wolf Computer_schem.pdf
(482.87 KiB) Downloaded 451 times

User avatar
Beedoola
Resistor Ronker
Information
Posts: 383
Joined: 01 Feb 2008, 22:52
Location: Bay Area, CA
Has thanked: 15 times
Been thanked: 32 times

Post by Beedoola »

IvIark wrote:Thanks cj, here's a quick layout if anyone wants to try it:

[ Image ]
For those that are interested. I built a WCPU using IvIarks layout but changed a few things, which are listed below and correspond to the schematic I attached in my last post:

The 1k resistor goes from the Emitter of Q3 to ground.

I tried the 10k for the Sag (I used 5k on the clone I built) and reverted back to the 5k - Has more useful oscillation and range.

For the Sag control - Lug 3 goes to 9v, Lugs 1 and 2 go to lugs 1 and 2 for the Bias control, and both go to the location in Ivlark's layout - top left/ 4.7k resistor.

Post Reply