Paul Cochrane - Timmy  [traced]

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beedotman
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Post by beedotman »

jymaze wrote:Or 33nF in parallel with 4.7nF... It would be quite close.
Yup, this should do the job as well.

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paulc
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Post by paulc »

The 33nf cap will raise the -3dB point of the filter from 1235hz to 1460hz. That's less than 1/10th of an octave which would be very hard to hear.

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Post by paulc »

paulc wrote:The 33nf cap will raise the -3dB point of the filter from 1235hz to 1460hz. That's less than 1/10th of an octave which would be very hard to hear.

Can't do math... It's more like 1/5th octave. Still not enough of a difference to call it a new design.

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madbean
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Post by madbean »

18991751.jpg

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TheLemon
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Post by TheLemon »

madbean wrote:
18991751.jpg
hahah

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beedotman
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Post by beedotman »

Guys... I have a question, maybe stupid, but... :blackeye

In Timmy we have got max gain resistor (3K3 in this case) going from IC leg 2 before Bass cut capacitors going to Vref.
In TS type pedals it is oposite - first is cap, then resistor responsible for max gain of pedal (4K7 in stock circuit).

Is this make any difference what is connected to Vref? :scratch:

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Post by phibes »

Order doesn't matter, it's a RC filter. Will work the same either way.
GuitarlCarl - "TGP = The Gear Polishers"

Image Ken

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beedotman
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Post by beedotman »

phibes wrote:Order doesn't matter, it's a RC filter. Will work the same either way.
Thanks! :thumbsup

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chrills
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Post by chrills »

Hi! I'm another Timmy clone builder, with a small problem.

The bass an treble pots only works in an very short part of the turning range - does anybody have an idea of what mistake I made, or if they are supposed to function like that?

Kindly,
Christian

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Post by batteryacidtea »

Are you using the right taper pots?

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chrills
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Post by chrills »

Yes.. well I guess so, 50K audio, both have the center leg connected to one of the outer legs.

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Post by atreidesheir »

Is the Timmy the 2nd best analyzed circuit after the TS?
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Post by paulc »

chrills wrote:Yes.. well I guess so, 50K audio, both have the center leg connected to one of the outer legs.
Which outer leg? That makes a big difference. It should be wired so that at zero or 7'o'clock the element is shorted out.

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Post by paulc »

atreidesheir wrote:Is the Timmy the 2nd best analyzed circuit after the TS?
I don't think so. The klon has it's own sub forum here.

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Post by IvIark »

The Timmy is still the 2nd most analysed circuit, but the Klon diodes is first. No one analyses the TS any more, we all just wait for the 78th revision of the Eternity to see what's happening 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

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Post by atreidesheir »

paulc wrote:
atreidesheir wrote:Is the Timmy the 2nd best analyzed circuit after the TS?
I don't think so. The klon has it's own sub forum here.
good point though.

I lose interest in Klon after the dual gain pot. I like that.
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Post by Seiche »

chrills wrote:Yes.. well I guess so, 50K audio, both have the center leg connected to one of the outer legs.
yeah one side makes it go zap, all there or all gone, and one side makes it be gradual.
remember the timmy has treble and bass CUT, which means the bass and treble REDUCE when you turn the knobs to the right.

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chrills
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Post by chrills »

Seiche wrote:
chrills wrote:Yes.. well I guess so, 50K audio, both have the center leg connected to one of the outer legs.
yeah one side makes it go zap, all there or all gone, and one side makes it be gradual.
remember the timmy has treble and bass CUT, which means the bass and treble REDUCE when you turn the knobs to the right.
Exactly... zap on the last 10%. But I guess it doesn't matter if the cut is in the beginning or in the end of the turn..?

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Post by Seiche »

chrills wrote:
Seiche wrote:
chrills wrote:Yes.. well I guess so, 50K audio, both have the center leg connected to one of the outer legs.
yeah one side makes it go zap, all there or all gone, and one side makes it be gradual.
remember the timmy has treble and bass CUT, which means the bass and treble REDUCE when you turn the knobs to the right.
Exactly... zap on the last 10%. But I guess it doesn't matter if the cut is in the beginning or in the end of the turn..?
well it just means you wired the pot wrong. an audio pot is not symmetrical in that sense. you have to switch the wires going to lug 1 and 3 on each pot and then you should get a pot that gradually reduces bass/treble when turned to the right. that's how the original timmy works. If you prefer it the way you have it, you need an antilog/revlog pot.

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chrills
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Post by chrills »

Thanks a lot, I will try that, now it also make sense to me with the rev log.
Love your avatar btw :0)
/ Christian

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