Korg NTS1 Usb Noise Fix, caps!

[Re8et]

I just soldered two small 10pf 15v Electrolytic caps on my NTS1.
One after the USB input, on V+ and GND, and another on the bottom
of the top plate on the test pads, between 3,3+ and GND also.
Usb noise level went down from unbearable to silent!

I got no pics but the solder work was pretty easy.
the top plate pads has text, whilst the usb needed just a
quick voltmeter test to find the 3,3+ rail pad and GND.

1KORG+NTS1-3.jpeg (208.23 KiB) Viewed 1081 times

[hamsterfactor]

I haven’t put mine together yet. Is this a known common problem?

[Re8et]

I haven’t put mine together yet. Is this a known common problem?

I don't know

[Julien]

Hello !

I've just created an account for this discution on NTS-1 usb noise and share my feedback.
I use it with a Korg SQ-1 and a Tascam DR-40. Everything is either powered by a power bank or a chinese usb power socket (for travelling or at my desk).
Usb noise was unbearable, huge hiss, almost half the level of the sound comming out of the NTS-1. And yes it seems to be a recurring problem.

So I decided to try this fix, except that I used ceramic caps instead of electrolytics. I dont know if it has an influence but I couldn't find electrolytic caps with such tiny value in my local shop.

Went for them any way. Noise went from unbearable to the sound of a kids anime tiny helicopter. Sound funny, not too loud. You know it's there (like the noise from a Tascam PortaStudio tape deck) but at least it doesn't cover the oscillator sound, so it's acceptable in the aforementioned setup.

Couldn't have total silence, maybe due the caps type, I don't know. Maybe on day I'll try with different caps to see...

An other work around (at least for my setup) is to plug the NTS-1 or the DR-40 on a separate usb socket. It's certainly ground loops that the NTS-1 doesn't like.

Even if it's not perfect, at least it's working, so thanks to Re8et !