help splitting signals at the beginning of circuit (please x)

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gods-and-ghost-light
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help splitting signals at the beginning of circuit (please x)

Post by gods-and-ghost-light » Thu Feb 18, 2021 12:35 pm

Really struggling with this seemingly basic task. I can't figure out how to properly separate the dry signal from the wet signal, in this case; a pt2399 delay circuit. I have buffered the input guitar signal which is clean but the buffered signal then really distorts when it hits the delay, the delay is fine if the signal is unbuffered. I've tried resistors and it still distorts but I just may not be setting them up correctly (i've also tried following schematics of other PT circuits and I cant get it right). Would this be to do with the input circuitry on the delay? The type of input buffering? Also how do I separate it at this point so that I have a dry and wet I can blend? I'm using tl072's as the op amps

Appreciate any help, thanks

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plushterry
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Re: help splitting signals at the beginning of circuit (please x)

Post by plushterry » Thu Feb 18, 2021 12:41 pm

You will have a lot more luck here if you can post some sort of schematic of what you've done.

The PT2399 wants quite a low input voltage so you may just be hitting the input too hard.

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plushterry
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Re: help splitting signals at the beginning of circuit (please x)

Post by plushterry » Thu Feb 18, 2021 2:11 pm

https://www.electrosmash.com/pt2399-analysis - this is a really good breakdown of how the chip works and how to use it. defo worth a look if you havent seen it already.

Section 5 has a bit on input levels, they say "0.5 to 1Vrms (1.4 to 2.8 Vpp)" as a guide, so low-ish by synth standards

jorg
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Re: help splitting signals at the beginning of circuit (please x)

Post by jorg » Thu Feb 18, 2021 2:39 pm

plushterry wrote:
Thu Feb 18, 2021 12:41 pm
You will have a lot more luck here if you can post some sort of schematic of what you've done.
I second that. It's literally impossible to provide any assistance on a question like this, without a schematic.

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EATyourGUITAR
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Re: help splitting signals at the beginning of circuit (please x)

Post by EATyourGUITAR » Thu Feb 18, 2021 3:22 pm

Post the buffer circuit with information about the amplitude of your test signal before and after the buffer.
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