# Dark Rift Delay noise in the repeats



## Reinholder (Nov 5, 2020)

Hi all, recently finished the dark rift delay and am noticing a overlay of white noise/fizz on top of the repeats. I've searched through the forum and found a suggestion to add a green led between the 7th pin and 3rd pin of the PT2399 may potentially calm the noise a little. I gave that a try and it didn't seem to help with the noise (it did reduce the volume of the initial repeat slightly and I can see the led light occasionally when picking hard). 
I've also read a bit about PT2399's and seems like a bit of noise is to be expected when used in delay effects but was just wondering if the noise I'm experiencing here is just standard PT2399 things or not.
Wondering if anyone has the real version of the pedal this one is based on, and if so, is the white noise a feature?
Thanks


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## zgrav (Nov 5, 2020)

without seeing your board it is hard to know if you have a construction/parts issue contributing to what you are describing, but if everything works OK except for the fizz it could be your PT2399 chip.  there is a lot of variation in how clean the output is on those from chip-to-chip.  by all means sub in another if you have it socketed to see if you hear a difference.  and FWIW, I always suggest using a socket for PT2399 chips for this reason, and suggest you have more than one of the chips to find the best one in the bunch for that pedal.


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## Reinholder (Nov 5, 2020)

Thanks Zgrav. Everything seems to work ok besides the fizziness that sits on top of the repeats. I'd socketed the chip and have swapped a couple that I had but it's fairly consistent. I'm thinking that maybe it's just how it is, but have never played an original or built another to compare so was interested if it was a normal feature.

Here's a gut shot if it helps.


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## zgrav (Nov 5, 2020)

one other suggestion is to try a different power supply or try plugging your power supply into another outlet in your place to test the pedal.

do you only hear the hiss when the wet signal is in your mix?  or do you hear it in the dry  signal too?  I think the noise is from your PT2399 IC but it could be a power supply issue.  Some pedals are more sensitive than others.


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## Reinholder (Nov 6, 2020)

Thanks I'll try a different outlet tomorrow and see if it helps. The hiss/white noise is only in the repeats (so when the pedal is engaged and I hit a note), there's no noise other wise.


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## susie_1987 (Mar 2, 2021)

In my experience it gets super fizzy when you're all the way out in the 600ms range. values under that sound normal


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## benja_t (Apr 21, 2021)

Any solutions on this? Im having the same issue


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## Betty Wont (Apr 21, 2021)

Likely it is inherent to the chip itself. I've not heard a pt2399 delay that has an acceptable level of hash noise in the repeats. Almost as bad as bbd delay,


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## Reinholder (Apr 25, 2021)

benja_t said:


> Any solutions on this? Im having the same issue


In the end I arrived at the conclusion that it was probably just the nature of the chip. The led trick did reduce the harshness but it was a bit of a trade off in terms of the volume. The only way I can really describe it is that the signal going in to the chip is loud to the point it's clipping and then you're hearing that clipping in the repeats. 

I put a video up here:


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## giovanni (Apr 25, 2021)

Uhm I’m not familiar with how the PT2399 works internally but maybe increasing R7 or reducing R9 would reduce the gain into the input (the gain of the inverting stage is roughly -R9/R7) and thus minimize the clipping. Before you do that, what happens if you turn your guitar volume down to 2-3? Does the clipping diminish? If so, my theory is probably correct.


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