Boscorelli projects...functioning circuits or theoretical jump off points?

[skiraly017]

Another Boscorelli project that I just can't get to work. Three times I've checked my work and still no go. I don't think it's me as I don't seem to have this issue with any other projects so I have to wonder if these are just circuits that should theoretically work. If you've gotten a Stomboxology or Stompbox Cookbook project to work I'd like to hear about it. Which project was it? Did it fire up right away or was there troubleshooting involved? Where you impressed by it or no? Thanks.

[soggybag]

Which project did you build that did not work?

I built Boost-o-matic IV from Stompboxology and it worked the first time. This is a simple treble booster so there wasn't much that could go wrong and the complexity was minimal.

http://www.webdevils.com/stompbox/?p=15

[R.G.]

Boscorelli's designs are descended from analog synthesizers, as opposed to classical pedal effects style. It's easy to pick this out because most of them use higher voltage bipolar supplies. The 9V battery is very much a basic design rule for pedals for historical reasons.

As such, they are more complex than basic pedals, and they rely on synth-style design techniques. This is necessarily bad, just more complicated, with more things that have to be right before you have a working pedal.

I was interested in Boscorelli's stuff for technical reasons, but I think they're outside the range of what we consider pedals these days.

They'd make good filling for a set of modules like my steel-studs modular approach; that one is right out of analog synth practice, too. 

[soulsonic]

They are begging to be put into Vector Pak modules.

[oldschoolanalog]

I've built several from the "Forbidden Red Cookbook" . The only ones of note so far are "sustain-o-matic", an optical compressor (think CA comp, LA light, etc.). Good, but nothing new or groundbreaking. On the other hand; "swirl-o-matic", an LM13600 based 4QM distortion is a real beast. This one however required some tweaking of component values to get it to my liking. A good bit of time at the protoboard to get it "just right". So to answer your question, yes, they are functional circuits. But IMHO really better for reference as "theoretical jump off points".
All the Best!
osa

[JDoyle]

I don't think Boscorelli ever met a signal that didn't need to be buffered, and if he did, he gave it a gain of 10.

R.G. hit it on the head, Boscorelli came from the synth world, which is why there are so so many op amps, the bipolar supplies, his long sections on voltage control, etc.

I look at his stuff as a mix of the practical and theorhetical. The engine, purpose, or heart of each of his circuits is usually worth using or exploring, but the supporting subcircuits around it that get the guitar signal (and even sometimes the control signals too) to and from those engines are usually too complex and Rube Gordberg-ish to be of any use in reality. You just don't need a quad op amp on board when four discrete JFET buffers take up less space and are more flexible in terms of layout...

[Gabriel]

Today i had finished and tested his design for the Attack-o-Matic. It's a volume ramp circuit, using quad opamps and a ne570 (difficult to find).
It works better than the Slow Gear and the Paia Gator. It can manage 2 inputs, 4 patterns of ramping for each input.

The only thing i don't like: In one of the ramp selection, you can hear a kind of "bump" when it cuts the sound.

Nice circuit for long swells and fast attacks.

[moosapotamus]

Gabriel - I tried to reply to your PM, but your inbox is full. Nice to know that the Attack-O-Matic IV worked out well for you. I might have to try that one.

On the other hand; "swirl-o-matic", an LM13600 based 4QM distortion is a real beast. This one however required some tweaking of component values to get it to my liking. A good bit of time at the protoboard to get it "just right".

Dave - I can't seem to fine the Swirl-O-Matic. Are you (maybe) thinking of the Dostort-O-Matic V? I've built that one and it is a pretty unique sounding distortion.

~ Charlie

[Paul Marossy]

Dave - I can't seem to fine the Swirl-O-Matic.

Me either. It's not in my copy...

[oldschoolanalog]

It's the 4QM project. Just realized he said in the text "I almost named this swirl o matic". Sorry for the confusion. 

[Paul Marossy]

It's the 4QM project. Just realized he said in the text "I almost named this swirl o matic". Sorry for the confusion. 

What project number is that in the book?

[moosapotamus]

Okay... Swirl-O-Matic = Distort-O-Matic V  (proj No. 17) 

... that's the one that I built, too. Does sound pretty cool.

~ Charlie

[Paul Marossy]

The Distort-O-Matic V.... that looks like an interesting project.

[danielzink]

I built the Echo-matic recently.

Works well - for a short/slapback style echo.

Dan

[cathexis]

I built the Vibrato-Matic III, and I like it a lot. Subtle, but musically useful right through the control ranges.

http://www.aronnelson.com/gallery/main.php/v/cathexis/Veroboard+Layouts/Vibrato-Matic+III/

[Gabriel]

For those who want to test the Attack-o-matic IV.

Note: The TL064 were a Little bit noiser to my taste, so Mark H, recomended to use the TL074 instead of the TL064 for the audio section, now it sound perfect and clear.

if anyone need build-advice, just let me know.