Frantone - Peach Fuzz  [traced]

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

Postby super velcroboy » 01 Dec 2007, 12:57

hi guys,
i took a look at the guts for the peachfuzz again tonight. I got a little crazy and went ahead with a preliminary schematic. I got confused by the relay. Haven't seen too many. I'm way too tired right now, so if someone could help me verify it, I'd appreciate it. Otherwise, it'll get done eventually ;)

http://farm3.static.flickr.com/2272/207 ... c096_o.png
Last edited by super velcroboy on 02 Dec 2007, 04:03, edited 1 time in total.
super velcroboy
 

Postby snail » 01 Dec 2007, 20:08

Thanks for sharing!
I've finished doing this one and it does work, but in your schematic pin 1 of the second LM (the one closer to the tonestack) should not be conected to pin5, leave it unconected.
I built it without the relay and transistor, so my validation would not include this part.

IMO it's more of a dirty wooly distortion than a fuzz. A good distortion tho!

It doesn't have the dynamics and cleanup abilities of a true trannie fuzz. BTW I'm yet to see a good IC fuzz.

Does the original peachfuzz clean up nice with the guitar volume down?

snail
snail
Solder Soldier
 
Posts: 202
Joined: 30 Aug 2007, 01:41
Has thanked: 0 time
Have thanks: 2 times

Postby super velcroboy » 02 Dec 2007, 00:46

snail wrote:
IMO it's more of a dirty wooly distortion than a fuzz. A good distortion tho!

Does the original peachfuzz clean up nice with the guitar volume down?



hi snail, you're welcome.
yeah you're right. I was going off the photo. pin 1 on the 2nd 386 is left open. Did you use my schematic or the one by bajaman?

it sounds more fuzzy with the tone and fuzz controls turned up. The bottom frequency is huge. It doesn't clean up too good. I've kept it on my board because i haven't played anything better yet. -Ben
super velcroboy
 

Postby snail » 02 Dec 2007, 00:57

I started my pcb on Baja's schemo, then the part after the last IC was not acurate and made the pedal sound funny, so I keept it on the drawer waiting on new info, as soon as I corected my old board with your schemo (tonestack and 100K pulldown after input R) it was sweet!
I'll be posting a layout for this one tomorow if I can, for my old design is still incorrect, and in the urge of seeing the thing work soon I did some messy job using the old board.
Another thing: I used a TL071 for the first IC as I didn't have the original one, hope it doens' differ in sound too much!

Love the graphics of the original Peachfuzz, helluva good taste!

snail
snail
Solder Soldier
 
Posts: 202
Joined: 30 Aug 2007, 01:41
Has thanked: 0 time
Have thanks: 2 times

Postby super velcroboy » 02 Dec 2007, 04:08

snail wrote:I'll be posting a layout for this one tomorow if I can, for my old design is still incorrect, and in the urge of seeing the thing work soon I did some messy job using the old board.
Another thing: I used a TL071 for the first IC as I didn't have the original one, hope it doens' differ in sound too much!


thanks snail!
I love to see that layout! ;)
I had some time today and fixed some errors and optimized things a bit.
I think the schematic is mostly correct now. The relay section I'm not perfectly sure about. There are about 3 radial electrolytics that bajaman indicated as polarized. They did looked nonpolarized to me.

i updated my other post with the updated schemo. ;)
http://farm3.static.flickr.com/2272/207 ... c096_o.png
super velcroboy
 

Postby jakerandall » 02 Dec 2007, 07:04

This is very interesting I have to say this is the first opamp fuzz that I have seen. I had one of these for a while but never bothered to take a peak. I figured it was just a big muff clone therefore I wasn't too interested. Its a cool sounding fuzz just a shame that it doesn't clean up all that well. And if I remember correctly the tone knob seemed a bit off.
jakerandall
Breadboard Brother
 
Posts: 56
Joined: 03 Nov 2007, 10:46
Has thanked: 0 time
Have thanks: 0 time

Postby Barcode » 02 Dec 2007, 08:57

i have to say, what is so desirable about a fuzz or distortion "cleaning up well?" i say, you want clean, turn off the pedal.

anyhow, all this talk of no good opamp fuzzes leads me to believe no one has built the red fuzz on ggg's site. EXCELLENT fuzz...
User avatar
Barcode
Diode Debunker
 
Posts: 821
Joined: 27 Sep 2007, 18:03
Has thanked: 14 times
Have thanks: 35 times

Postby jakerandall » 02 Dec 2007, 09:38

my problem with cleanup is simple. I don't want clean I just want to roll off for a little bit less gain. Alot of fuzzes seem to sputter and gate when you do this. This is not very desirable to me.
jakerandall
Breadboard Brother
 
Posts: 56
Joined: 03 Nov 2007, 10:46
Has thanked: 0 time
Have thanks: 0 time

Postby bajaman » 02 Dec 2007, 11:12

The schematic is still not correct!!!!
The 1uf electrolytics may well be non polar types - i just wish someone would post some decent pictures of this pedal :roll: :roll: :roll:
None of the photos show the hidden resistors or the potentiometer wiring correctly :(
Anyway the 1uf capacitor connected to the base of the 2N5088( or whatever this transistor is )is shown shorted out in super velcro's schems.
It should be connected in parallel with the 10k resistor also connected to the base - of this I am certain - check my rough drawing earlier in this thread :wink:
How sure are you that the input resistor in the voltage divider is 100k and not 1M as I speculated have you measured it's resistance - what are the colour codes on the resistor body :?: :?: none of the photos posted so far show this resistor clearly - 100k seems a bit low :?
It appears that the 2N5088 (or whatever) is used to mute the output of the effect unit. When the footswitch is closed the led indicator is energised the base of the transistor is grounded through the parallel 10k and 1uf capacitor, and is therefore turned off - this creates a high impedance path from collector to emitter and unmutes the tone control at the output of the distortion stage. The relay is of course energised as well, and switches the true bypass switches on the input and output to engage the effect. ( I drew this incorrectly in my rough sketch :oops: :oops: )
Of course when the footswitch contacts are open the led indicator turns off, the transistor is biased on and creates a low impedance path between the collector and emiitter of the NPN transistor -this effectively shorts the tone control to ground and mutes any leakage from the high gain distortion from getting into the clean bypassed signal - the relay contacts change to the true bypass condition.
An advantage of this switching technique is you only require a single pole single throw (SPST) latching footswitch. A disadvantage is the extra DPDT relay required to perform the true bypass switching.
bajaman
User avatar
bajaman
Old Solderhand
 
Posts: 4390
Joined: 26 Jun 2007, 22:18
Location: New Brighton, Christchurch, NZ
Has thanked: 475 times
Have thanks: 1687 times

Postby analogguru » 02 Dec 2007, 11:47

bajaman wrote:The schematic is still not correct!!!!
The 1uf electrolytics may well be non polar types - i just wish someone would post some decent pictures of this pedal :roll: :roll: :roll:
None of the photos show the hidden resistors or the potentiometer wiring correctly :(


Dont be so nervous.....IMHO the electrolytics are polarized.
With a little patience and comparision you can recognize the poti wiring from the pictures....

What can´t be seen are the values of the marked resistors in my photo above and if ther is hiding a resistor beside the 10n cap as written in the component picture... but it seems to....

For this reason the tone-section equals to my findings.

How sure are you that the input resistor in the voltage divider is 100k and not 1M as I speculated have you measured it's resistance - what are the colour codes on the resistor body :?: :?: none of the photos posted so far show this resistor clearly - 100k seems a bit low :?


With a good graphic program you can be absolutely sure - from my picture above:
input divider

It appears that the 2N5088 (or whatever) is used to mute the output of the effect unit. When the footswitch is closed the led indicator is energised the base of the transistor is grounded through the parallel 10k and 1uf capacitor, and is therefore turned off - this creates a high impedance path from collector to emitter and unmutes the tone control at the output of the distortion stage. The relay is of course energised as well, and switches the true bypass switches on the input and output to engage the effect. ( I drew this incorrectly in my rough sketch :oops: :oops: )
Of course when the footswitch contacts are open the led indicator turns off, the transistor is biased on and creates a low impedance path between the collector and emiitter of the NPN transistor -this effectively shorts the tone control to ground and mutes any leakage from the high gain distortion from getting into the clean bypassed signal - the relay contacts change to the true bypass condition.
An advantage of this switching technique is you only require a single pole single throw (SPST) latching footswitch. A disadvantage is the extra DPDT relay required to perform the true bypass switching.
bajaman


If the "muting" does anything then the muting (for high frequencies) occurs only during switching periods (for high frequencies).

If the footswitch is not closed the 1 µF electrolytic is charged via the relais coil in parallel with the LED/1k. When it is charged we have a voltage-divider at the base of Q1 10k/390E which is connected to 9V. If we neglect the coil-resitance and 100Ohm resistor we will find at the base a voltage of 0,337 V what is not enough to turn the transistor on.

Now if the footswitch is closed the cap will be discharged but there will be 0V at the voltage divider.

Only if the footswitch will be opened (causing the Fuzz to go from ON to the OFF-state) the 1µF cap is like a shortcut and is shorting the 10k resistor. This produces a voltage determined by 9V - LED-voltage = 7,4V ..... Conected to this "voltage source" now is a divider 1k/390E which will caus a voltage of 2,07V at the base of Q1 as long as the 1µF capacitor is not fully charged. when it is charged: see above....0,337V

analogguru
There´s a sucker born every minute - and too many of them end up in the bootweak pedal biz.
analogguru
Old Solderhand
 
Posts: 3285
Joined: 26 Jun 2007, 14:58
Has thanked: 0 time
Have thanks: 117 times

Postby snail » 02 Dec 2007, 11:49

I've come to this so far:

Image

Image

I haven't verified this one, as I said before I've built a different board based on previous schematics, so this is an update. Since my board is messy but works I'm not going to remake all over again, so if someone builds this please give me a thumbs up, if something is wrong I'll be glad to correct it. I can also email the source file upon request.

Dunno if the electrolitics are polarized or not, but it works with the orientation I've posted, or else just use plain old poly 1uf types.

Please note I'm using TL071 for the first stage, pinout differs from TL022.

Hope it helps

Snail
snail
Solder Soldier
 
Posts: 202
Joined: 30 Aug 2007, 01:41
Has thanked: 0 time
Have thanks: 2 times

Postby bajaman » 02 Dec 2007, 11:55

Thanks AG for your excellent explanation regarding the muting circuit :wink:
bajaman
User avatar
bajaman
Old Solderhand
 
Posts: 4390
Joined: 26 Jun 2007, 22:18
Location: New Brighton, Christchurch, NZ
Has thanked: 475 times
Have thanks: 1687 times

Postby bajaman » 02 Dec 2007, 11:57

I have the PCB track layout cloned - well 99% done - I will post soon - unless someone beats me too it :lol:
bajaman
User avatar
bajaman
Old Solderhand
 
Posts: 4390
Joined: 26 Jun 2007, 22:18
Location: New Brighton, Christchurch, NZ
Has thanked: 475 times
Have thanks: 1687 times

Postby super velcroboy » 02 Dec 2007, 12:47

i have the peachfuzz in my hand as i am typing this.

The 1uF radial caps are weird and i can't tell if they are of polar types. There are marking on the side, but the 1uf coming from the pin 1 of TL022 has markings on the side that do not line up with the lead, which led me to believe it's nonpolar. But anyway, it shouldn't matter right?.. as we can replace nonpolar for polar?

I am positive the tranny is 2n5088....

you are correct, the 10 uF and 10k are in parallel with each other coming from the base of the tranny on one end and to the switch on the other. That's what i meant to draw up last night, but it was like 3 am in the morning. Speaking of which, it's 3 am right now :lol:

the input resistor is indeed 100 k. Measured it ;) brown black yellow...yellow is hard to see on a carbon comp ;)

What can´t be seen are the values of the marked resistors in my photo above and if ther is hiding a resistor beside the 10n cap as written in the component picture... but it seems to....


there are 2 resistors not shown in your photo. Sorry, i didn't get a chance to take more photos, so you just going to have to take my word for it ;) A 47k under the orange 10nF and a 10 k underneath the big orange 0.47F cap. It should be correct as I've shown it.

Ben
super velcroboy
 

Postby bajaman » 04 Dec 2007, 09:58

User avatar
bajaman
Old Solderhand
 
Posts: 4390
Joined: 26 Jun 2007, 22:18
Location: New Brighton, Christchurch, NZ
Has thanked: 475 times
Have thanks: 1687 times

Postby modman » 04 Dec 2007, 15:36

Fran's Peach can now be enjoyed from even our White List :wink:

Great work guys!
Please, support freestompboxes.org on Patreon for just 1 pcb per year! Or donate directly through PayPal
User avatar
modman
a d m i n
 
Posts: 4477
Joined: 19 Jun 2007, 17:57
Has thanked: 3555 times
Have thanks: 689 times

Postby DougH » 04 Dec 2007, 19:30

Just to clear up some previous comments:

It's not an "op amp" fuzz. The LM386 is an audio amplifier.

"Clean up" is desired by guitarists who like to remote-control their tone with the volume control of their guitar. I play this way myself- turn on one distortion box and leave it on for a song, controlling it with my guitar volume.
DougH
Transistor Tuner
 
Posts: 1104
Joined: 18 Aug 2007, 05:53
Has thanked: 4 times
Have thanks: 24 times

Postby The Rotagilla » 04 Dec 2007, 19:43

Thanks Bajaman.

I can't listen to the sound samples at work. Is this worth building?
User avatar
The Rotagilla
Diode Debunker
 
Posts: 732
Joined: 20 Aug 2007, 19:24
Has thanked: 6 times
Have thanks: 60 times

Postby super velcroboy » 04 Dec 2007, 20:07

bajaman wrote:Peach Fuzz PCB

Peach Fuzz Layout

enjoy :wink:
bajaman


that looks awesome bajaman!
Last edited by super velcroboy on 04 Dec 2007, 20:11, edited 1 time in total.
super velcroboy
 

Postby analogguru » 04 Dec 2007, 20:08

The Rotagilla wrote:Is this worth building?


I don´t know.... but you can put all from your junk-box inside a pcb.....

Did you know ?
The LM386 is one of the noisiest and cheapest amp-IC´s... but it also distorts like hell...:
http://www.wentztech.com/radio/Misc/lm3 ... -lm386.pdf
http://ludens.cl/Electron/audioamps/AudioAmps.html
http://www.ciphersbyritter.com/NOISE/SPEC386.HTM
http://www.w9aiu.org/MoretipsQRP.htm

and you can make a ghostbox from LM386:
http://www.spiritsearchsociety.com/theghostbox.pdf

so it´s really amazing, that every junk can be used to make money....

Interesting the "design" of the second LM386:

A LM386 has a typical input impedance of 50k.
Now we have a series resistor of 120k to the input.
That means we have a voltage-divider of (120k+50k) 170k/50k which means that the signal is attenuated approx. 10dB.
than we have an 18p cap in parallel to the 50k what means the slope will be reduced to 3dB/octave... in the best case.....

Since an 18pF has an reactance of 8MOhm at 1kHz, 800k at 10kHz and 400k at 20kHz it will not influence the audio-signal in any way....

So much to the design-skills of Bootweaker Fran.

But to be honest and fair I have to say that I like the case....

So: take the money and run.... :wink:

analogguru
Last edited by analogguru on 04 Dec 2007, 21:51, edited 2 times in total.
There´s a sucker born every minute - and too many of them end up in the bootweak pedal biz.
analogguru
Old Solderhand
 
Posts: 3285
Joined: 26 Jun 2007, 14:58
Has thanked: 0 time
Have thanks: 117 times

PreviousNext

Return to Boutique Stompboxes dissected...

Who is online

Users browsing this forum: stelios and 5 guests