Noise in Bassdrum decay

My Nava has a noise floor in the decay phase of the bassdrum. I've recorded a .wav file here: https://florianmoser.ch/909-noise-decay.wav

It is recorded right out of the BD-output, but the noise is also there on the mix-output.

Does anyone else have this issue?

Could it be this ?

gihaume wrote:Could it be this ?

Thanks, Gihaume. I'm currently unable to check my power supply (it is installed somewhere deep behind a rack). But I recall reading this thread, when I was building the Nava. So I'm pretty sure I took a power supply with >= 1A. But I indeed have a little bit of distortion on the mix out (only visible on the sine wave, almost impossible to hear). And I have installed the Extra9 Kit. However, the noise I recorded is on the individual BD out.

So you don't have this noise in the decay phase of your unit? When recording the linked .wav file, the BD-decay was set pretty high (pot around 3 o'clock).

Finally I recall I had this. I probed the + and - 15v and found they had the small oscillation we hear on the bass drum. I could also hear it on the steiner parker filter.

gihaume wrote:Finally I recall I had this. I probed the + and - 15v and found they had the small oscillation we hear on the bass drum. I could also hear it on the steiner parker filter.

Thanks Gihaume. I guess I'll have to play with another power supply. Maybe simply use a toroidal transformer instead of a wall plug.

I just tried out a toroidal transformer, 15VAC 2.667A. On load (Nava on and playing a pattern) I measure 18VAC @ 970mA.

But still the same hissing on the BD decay. Gonna have to find something else.

I finally found the issue. This post helped me.

In the Bassdrum section, cable 1 and 2 (noise decay in/out) leading from the Nava to the Extra 9 board, must not be bundled with the other cables. There's indeed a crosstalk from noise to audio.

Simply separating these two cables and keeping them 2cm apart from the rest of the cables solves the problem!

flomo wrote: ↑Nov 12th, '22, 17:34 My Nava has a noise floor in the decay phase of the bassdrum. I've recorded a .wav file here: https://florianmoser.ch/909-noise-decay.wav Buildnow GG

It is recorded right out of the BD-output, but the noise is also there on the mix-output.

Does anyone else have this issue?

I'm having the same issue with noise floor in the decay phase of the bassdrum on my Nava! I listened to the .wav file you uploaded and it sounds exactly like what I'm experiencing.

I'm having the same issue with noise floor in the decay phase of the bassdrum on my Nava! I listened to the .wav file you uploaded and it sounds exactly like what I'm experiencing.

It's most likely noise from the other cables. Try to separate cable 1 and 2 from the bassdrum section from the rest of the cables (keep it as far away as possible) and there should be no more noise.