Messages

Re:  Topic: Can you up the fidelity changing out opamps?

Yeah, you can, but you might not like the results. (I have some recent posts regarding that).

There are people who say that changing opamps doesn't make a difference.  That's like color-blind people saying that there is no such thing as color, or people who can't have orgasms saying that there is no such thing as orgasms.
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I think I rather like the sound with the TL072.  Today, anyway.
I'm going to have to learn to not pursue technical perfection so much.
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I really do like the way that 5532s sound.
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I started with a 2134, but it was flaky and oscillatey.  When it worked, though, it sounded CLEEEEN.

Today I reverted to a TL072 and it sounds a little pasty but it's stable.  Only thing is, there have been a few times I had TL0-equipped pieces work fine at home and refuse to work on stage.
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Hello.  I have an Afterlife, for which a TL072 opamp is specified.

I think that my chain might be improved by having a TL072 in it but I've always had drive problems with TL0 op amps.  I would never connect one to the output jack of anything.  This is repeated experience talking.

So here's the Afterlife and here's one side of a TL072 pumping up control voltage into a 100uF capacitor.

Has anyone noticed any problems with this?

Thank you kindly.

No, but it is my first pedalboard....

Gotcha. Will do.

I don't think that that is true.  I'm looking at a little buffer card.  It has one terminal labelled "9 Volts" and another labelled "Ground".  You're saying that I should connect them together to the same place.  I don't see how that would work.

Hello.

Should I be concerned that standard pedalboard wiring has positive voltage on the outside of the connectors?  The panel-mount jacks that I am aware of have the outside terminal "grounded" to the chassis.  So your whole system is positive ground, which I guess is okay if there isn't a nine volt negative ground anywhere in the system.

Right?
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Is there a particular schematic you have questions about?

It's the Afterlife, the effect control pot in the path that provides current to the LED in the optoisolator.  It's not real obvious what this should be.  For instance I like linear volume controls and log tone controls in guitars for the way that they respond.  But this is a more mysterious application.

And complicating that, if the top half of the knob rotation gives me extreme compression, I'm going to want to decrease the percentage of that series resistance that is controllable, so the pot's whole range will be a useful range for me.  So what is half of a log pot?  And is half of a log pot still log? 

Guitar techs have real trouble understanding that if you want to eliminate wasted rotation on a tone pot, the pot value that you end up with is extremely politically incorrect.
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Well yeah, the schematic is what I'm looking at.  I know what it says.  I just don't know what it means.  If they just said "audio" or "linear" that would mean something.
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I've always been a little uncomfortable with misleading abbreviations.  For instance, when Madbean says to use a 100kA pot, does that mean 100k Audio Taper, or does that mean 100k "A Taper" which if you look it up on a pot data sheet might mean something completely different?

What does it mean really?

Thank you kindly.
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One would think that if germanium is good for the rectifier diodes, Schottky would be great.

Does anyone have any experience along these lines?

Thank you kindly.