Akai - Headrush E1  [schematic]

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Bernardduur
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Post by Bernardduur »

Hi all!

I got this Headrush E1 in due to some noise. There is a lot of 'clock noise' going on: a high pitch noise that is always in your signal and can't be dialed out. Quite loud, quite apparant, quite annoying. On the mix output the noise was loud; on the 'seperate head outputs' the noise was bearable.

I fixed part of it by replacing all filter caps with new versions. With this, the noise was bearable, but still in the signal. In the end I fixed the noise by adding 10n caps to ground on the 'head outputs' jacks. That fixed most of it and did give me no real coloration of the delays (as far as I can hear).

To my surprise the noise was partly back when I used the tap tempo switch. Not that loud as before, but annoying as I thought I fixed it. BUT, when I use the delay controls (manually set the delay time) the noise vanishes.

Pics:
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and the schematic:
Akai - Headrush E1.JPG
'No more....... loud music.......'
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