Prescription Electronics - Experience Octave Fuzz

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mcaviel
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Post by mcaviel »

in the second picture attached it seems like all pots are B100K

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SpencerPedals
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Post by SpencerPedals »

I breadboarded the swell part of this last week to see if it did anything at all with my non-octave pedal collection and it indeed did not. I was hoping for something from the Uglyface, but no luck. When my Tone Machine is done, maybe I'll revisit. I'm thinking one of the more complex swell/gate pedals is worth the time, to have something that works with everything.

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aquataur
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Post by aquataur »

mcaviel wrote:in the second picture attached it seems like all pots are B100K
Yes, but this is up til now the only source that claims so. Some of them are marked "log".
Mark you, it is also the only source that claims to be a P.E. descencant rather than foxxtone.
It probably does not make too much of a difference if you take 50k vs. 100k, but somebody might have found that a log pot better suits the adjustability in some cases.

Maybe Noel can shed more light on this.

have fun,

-helmut

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aquataur
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Post by aquataur »

I finally found it on this pagehttp://web.archive.org/web/200310082340 ... ience.html :applause:

The lord giveth to he who waiteth.
The page seems to be gone, that explains why no search engine finds it. I do not know who it belonged to. Credits to him/her anyways.
I only had two germanium diodes in my parts box, so I used silicon diodes for the octave part of the circuit and germanium OA90's for the clipping diodes. I used BC549 transistors because they're very cheap and have plenty of gain.

The basic fuzz sound is OK, but not great, sort of a compressed Bosstone sound. There are better circuits if you just want a straight fuzz. With the octave effect engaged it tracks reasonably well and sounds similar to a Superfuzz. If you play chords through it you get a really distorted wall of sound. Cool. Well, for about two minutes anyway.

The swell function takes some getting used to. Because it can only be used with the octave effect, I've found that it works best on the neck pickup with the tone rolled off and with the tone control on the box at minimum treble. In common with most octave devices, the best effect is produced on the upper strings around the 12th fret. If you try using it with a trebly signal the swell effect is lost altogether and it can get sputtery. Also, you need to be careful with your phrasing - if you try playing a flurry of notes, you'll just get garbage out of it. Of course, you might like that...

I wouldn't recommend this one as a first project; the wiring could get confusing if you haven't had much experience (no pun intended) and the three DPDT footswitches bump up the cost significantly.

have fun,
-helmut
Attachments
The pcb to complement the drawings shown earlier in this thread.
The pcb to complement the drawings shown earlier in this thread.
exp_pcb.png (5.09 KiB) Viewed 2609 times

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noelgrassy
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Post by noelgrassy »

The pots in mine are all 100K linear Alphas. The controls seem to work smoothly in terms of no
weird humps or hiccups when sweeping them. They provide a good range of control in the PE circuit.
I hope this helps,

Noel Grassy.
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B100K pots
B100K pots
PE Exp[1st versh=MINE!] Pron (18).JPG (812.29 KiB) Viewed 2580 times
Copyright does not protect facts, ideas, systems, or methods of operation, although it may protect the way these things are expressed. US Copyright Office

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aquataur
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Post by aquataur »

I worked quite a bit on the swell circuit, later more on that. :hmmm:

May I point out that you have made a small mistake on your redraw. Your drawing does not cohere to what you were saying a second later:
celadine wrote: Q1's collector is connected to Q2's base [...]
But maybe it does not make much of a difference, since R6 is fairly low value.

have fun,

-helmut

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celadine
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Post by celadine »

Thanks for catching that - here's the revised redraw:
Experience Swell.PNG
Experience Swell.PNG (5.76 KiB) Viewed 2518 times

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Post by aquataur »

I have fixed all problems with the swell. An incredible amount of work has gone into this.
As claimed a while ago, I have put all swell adventures on my pages for you to enjoy now.

have fun,

helmut

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Post by rousejeremy »

Great work Helmut. :applause:
I wish I kept up with this thread since I posted last.
aquataur wrote:I have fixed all problems with the swell. An incredible amount of work has gone into this.
As claimed a while ago, I have put all swell adventures on my pages for you to enjoy now.

have fun,

helmut

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Post by drbob1 »

It appears that PE is back in business, although it's not clear WHO is involved. Terry, from MusicToyz owns the website although Jack is name-checked on the home page:

https://prescriptionpedals.com

At $400 the Experience pedal seems to be WELL overpriced, but I'm guessing they're comparing it to $1k+ for the original units. Funny, the one I used to own I could never get the swell to work (but I didn't have the hindsight of the thread here to suggest I try different amps).

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Post by Electric Albatross »

I remember Prescription Electronics sent me a cassette tape demo of the Experience pedal in the mail in like 1994!
That was boutique marketing!
:horsey:

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