Retro Channel - The Fuzz [traced]

[iq01221]

this is so retro! like in the old days right

+1

[RnFR]

so they really got some fuzz chips made?? doesn't that cost a fortune? why would you bother to do something like that other than for use as a marketing tool? ease of construction I could see, but if they are getting it all assembled smd anyway, what's the point?

oh yeah, to stop people from reverse engineering it and finding out it's most likely a Si fuzz face.

I doubt they're"fuzz chips". Probably just a matched transistor array in a SO-14 package.
Prob. like one of these:
(the ones I reference are DIP-14 packages good for us diy'ers)

4 Matched PNP, hfe 75
http://www.mouser.com/ProductDetail/THA ... 2bi5wyo%3D
or
2 Matched NPN hfe 100, 2 Matched PNP hfe 75
http://www.mouser.com/ProductDetail/THA ... kVYQ%3d%3d

These are made by "That Corp." http://www.thatcorp.com/THAT_IC_Products.shtml. It was founded by Les Tyler and Gary Hebert who both formerly worked for DBX, I know atleast one of them is a guitar player and gear head too. They actually make alot of cool audio IC's, stuff like VCA's, preamps, line drivers, line recievers. A lot of big names use their stuff too. I believe the Seymour Duncan compressor is based around one of their VCA's and DBX uses their stuff too. I actually work about 5 min from their headquarters so I stopped by about 5 months ago and got a bag of free samples. After reading about the matched transistor arrays and noticing their nice low gains I immediately thought about using them for fuzz experiments. Haven't gotten around to it yet, been really busy working on other people's gear, but hopefully I'll have time soon. Can't wait to see the pics from ibodog2 and figure this one out and verify.

now that makes more sense. but it sure ain't no "proprietary chip set". doesn't there have to be more than one chip for a "chip set", anyway? it is a nice looking build, but they sure did a number on that IC!

[mictester]

Now that makes more sense. but it sure ain't no "proprietary chip set". doesn't there have to be more than one chip for a "chip set", anyway? it is a nice looking build, but they sure did a number on that IC!

I found that I had a large quantity of LM3084 transistor arrays, and used them for "Superfuzz" circuits (the long-tailed pair worked brilliantly in the octave circuit). I ended up with a spare transistor in the package, and used it for a Millennium Bypass rather than waste it!

[willc1968]

Wow! It looks like they took a belt sander to the chip.

[RnFR]

Now that makes more sense. but it sure ain't no "proprietary chip set". doesn't there have to be more than one chip for a "chip set", anyway? it is a nice looking build, but they sure did a number on that IC!

I found that I had a large quantity of LM3084 transistor arrays, and used them for "Superfuzz" circuits (the long-tailed pair worked brilliantly in the octave circuit). I ended up with a spare transistor in the package, and used it for a Millennium Bypass rather than waste it!

i was thinking the same thing- millenium bypass, o/p buffer, etc. matched sets would be fantastic for octave effects for sure. what about flip flop octave downs?

[KHELSTROM]

Thanks !
Are you 100% sure about where the traces from C4 and R10 terminate under the IC?
I'll make a schematic in Multisim today if I have time.

[Seiche]

this is so retro! like in the old days right

+1

ahahaha, typical coffee spit moment.

[MauroR]

My guess....


MauroR

[lance keltner]

Hey Guys,
Nice to see so much interest in what we are doing...
This is my first visit here. Do you do this to every manufacturers product line?



Lance Keltner
Retro Channel

[mictester]

Now that makes more sense. but it sure ain't no "proprietary chip set". doesn't there have to be more than one chip for a "chip set", anyway? it is a nice looking build, but they sure did a number on that IC!

I found that I had a large quantity of LM3084 transistor arrays, and used them for "Superfuzz" circuits (the long-tailed pair worked brilliantly in the octave circuit). I ended up with a spare transistor in the package, and used it for a Millennium Bypass rather than waste it!

i was thinking the same thing- millenium bypass, o/p buffer, etc. matched sets would be fantastic for octave effects for sure. what about flip flop octave downs?

I've tried that too with success. The 3084 has fairly low hfe transistors in it, and they're pretty good in Fuzz Face-type circuits. I've also used them in voltage-controlled amplifiers (like the old Moog circuit), and built tremolo pedals using them.

[mictester]

Hey Guys,
Nice to see so much interest in what we are doing...
This is my first visit here. Do you do this to every manufacturers product line?
Lance Keltner
Retro Channel

Many of them - especially the ones who goop their Tubescreamer-alike and claim that it's the Holy Grail of Tone!

[polarbearfx]

Now that makes more sense. but it sure ain't no "proprietary chip set". doesn't there have to be more than one chip for a "chip set", anyway? it is a nice looking build, but they sure did a number on that IC!

I found that I had a large quantity of LM3084 transistor arrays, and used them for "Superfuzz" circuits (the long-tailed pair worked brilliantly in the octave circuit). I ended up with a spare transistor in the package, and used it for a Millennium Bypass rather than waste it!

i was thinking the same thing- millenium bypass, o/p buffer, etc. matched sets would be fantastic for octave effects for sure. what about flip flop octave downs?

I've tried that too with success. The 3084 has fairly low hfe transistors in it, and they're pretty good in Fuzz Face-type circuits. I've also used them in voltage-controlled amplifiers (like the old Moog circuit), and built tremolo pedals using them.

Mictester your impressive. Very fast. I dig it.

[RnFR]

Hey Guys,
Nice to see so much interest in what we are doing...
This is my first visit here. Do you do this to every manufacturers product line?



Lance Keltner
Retro Channel

welcome to the forum, Lance. here at FSB, we like to learn things by dissecting circuits (it's pretty much the only way to learn about pedals these days), and in the process sometimes we find out which manufacturer's pedals live up to the marketing hype, and which ones fall short. anything you might want to add to the technical discussion is always appreciated.

Now that makes more sense. but it sure ain't no "proprietary chip set". doesn't there have to be more than one chip for a "chip set", anyway? it is a nice looking build, but they sure did a number on that IC!

I found that I had a large quantity of LM3084 transistor arrays, and used them for "Superfuzz" circuits (the long-tailed pair worked brilliantly in the octave circuit). I ended up with a spare transistor in the package, and used it for a Millennium Bypass rather than waste it!

i was thinking the same thing- millenium bypass, o/p buffer, etc. matched sets would be fantastic for octave effects for sure. what about flip flop octave downs?

I've tried that too with success. The 3084 has fairly low hfe transistors in it, and they're pretty good in Fuzz Face-type circuits. I've also used them in voltage-controlled amplifiers (like the old Moog circuit), and built tremolo pedals using them.

how about reverse polarity protection? buffered Vref?

isn't this the chip that George Tripps used for the swollen pickle? i can see no real advantage in a muff, other than simplicity of design, but it did make it unique.

[DrNomis]

That matches my (really screwed up) original pencil schematic. But I have no idea what Q1 and Q5 are doing there.

Aha, I think I know what Q1 and Q5 are doing, Q1 is set up as a bias current source for Q2, and Q5 is just setting the supply current for the power indicator led to a safe level...if I'm not mistaken, that is....

[DrNomis]

Ah no, Q5 is part of a voltage divider system to divide the +9V down to a lower voltage to be supplied to Q1, which in turn develops a bias supply for Q2, and the whole point is to get it well-regulated.....

[Dirk_Hendrik]

Ah no, Q5 is part of a voltage divider system to divide the +9V down to a lower voltage to be supplied to Q1, which in turn develops a bias supply for Q2, and the whole point is to get it well-regulated.....

Or is Q5 supposed to be a heat source keeping the temperature and therefore the sound stable?

[culturejam]

The LM3064 / LM3086 seems to match up with the pins.

lm3046.png (35.78 KiB) Viewed 2940 times

[culturejam]

Okay, so if there is fancy temperature-correcting biasing going on, then......why? Why would that be a problem with silicon transistors?

[RnFR]

Ah no, Q5 is part of a voltage divider system to divide the +9V down to a lower voltage to be supplied to Q1, which in turn develops a bias supply for Q2, and the whole point is to get it well-regulated.....

Or is Q5 supposed to be a heat source keeping the temperature and therefore the sound stable?

or is it just there to make us go ? a deception?

Okay, so if there is fancy temperature-correcting biasing going on, then......why? Why would that be a problem with silicon transistors?

I was wondering the same thing. it looks like this diode trick is usually used with Ge transistors in the textbooks.

[mictester]

What's that "substrate" label on pin 13 mean?

You're right. The "Substrate" pin needs to be grounded. If it isn't, you risk destroying the IC.

Incidentally, the pin 1 - 5 transistor pair with the common emitters are really good for a "Superfuzz".