For all of you noisy Rebote 2 users

[jlullo]

Hey guys,
I just completed my third rebote build.  The first was a 2.5, the second a 2.0 (which i prefer), and the latest a 2.0 also.  after i finished the latest build i was getting some slight oscillation and clock noise... sort of a high pitched whining.  It was almost like there were ghosts whispering whenever i turned it on   It got so bad that i couldn't even turn the repeat knob past 12 o'clock or the effect was unusable.  I remembered reading here somewhere that the two .0027 mf caps on pin 13 and 15 of the pt2399 were the ones that mostly controlled the clock noise, so i changed them out to match the rebote 2.5 (560 pf and .001 mf caps).  that KILLED the noise, and even better, cleaned up the distortion on the repeats when the delay time is slow.  It's almost 100% clean!  i hear a slight treble loss, but i've found that i can take care of that by playing around with different chips in place of the TL072 (specifically an OPA2132P).... i'm assuming this op amp is acting like a buffer in the circuit?

Anyways, if you are getting some nasty noise, try messing around with those two caps!

[John Lyons]

Thanks for the info.

John

[aledjack]

Thank you!! 

That's a great new! I have now finished the rebote 2 and the repeats had a little noise, in this evening I try this mod for the caps.

Ale

[Kornell]

Time to build a rebote2.  Thanks for the info.

[Mick Bailey]

Wow - just did the cap mod to my newly built Rebote 2. WHAT a difference. On long delays nearly all of the noise has disappeared between repeats and the tonal quality of the repeats is much better. Mine is a lot brighter and far more usable . I A-Bd the original caps three times and couldn't believe the difference. I would have thought that lower value caps should have increased the noise. Also checked the original values on my build - they were correct.

Talk about stupid - I wanted to build the Rebote 2.5 and downloaded (and built!) version 2 by mistake. Am I missing something, (apart from intelligence) - is the 2.5 that much better?

Any consensus?

Must say, I'm more than happy with the result and it beats the hell out of my Danelectro Reel Echo.

[Fp-www.Tonepad.com]

cool

[skiraly017]

I remembered reading here somewhere that the two .0027 mf caps on pin 13 and 15 of the pt2399 were the ones that mostly controlled the clock noise, so i changed them out to match the rebote 2.5 (560 pf and .001 mf caps).  that KILLED the noise, and even better, cleaned up the distortion on the repeats when the delay time is slow.

This is interesting becuase as I understood things, the two .0027's were supposed to help give it that "analog" feel by rolling off the treble on each successive repeat. I played around with these two caps awhile back and found that I could drop to .0018 before the repeats started to sound metallic/processed. You've dropped way below what I did and you're saying all works well and the delay still sounds natural? I'll have to give it a try.

[Wounded Paw]

I just built my fourth or fifth Rebote 2.5 and for the first time the noise on long delays is showing up for me.   I've used pretty much identical components on each one, was I just unlucky this time?  I tried changing the .001 mf cap on pin 13 of the pt2399 to a 680 pf cap but it had no effect.  What to do next?