KVR Audio

zerocrossing · Post by **zerocrossing** » Sun Aug 27, 2023 2:10 am

michat wrote: Fri Aug 25, 2023 1:42 pm Hey guys,

I hope you can help.
I've got several analog synthesizers connected into a 24 channel soundcraft mixer.
All of them produce a 10 kHz noise / spike whether they are played or not. As soon as I pull up the fader on the desk, it's there permanently.
The synths are a Prophet rev2, Dreadbox Medusa, Behringer Neutron, TD3, and some drumcomputers as well.
The thing they have in common is that they are all hooked up via USB on a powered external hub.

Could that be the problem - and if not - what could it be?

Thanks in advance.

I’m sure that’s the problem. Get yourself a good USB isolator, but make sure it works with the level of USB version you need.

thecontrolcentre · Post by **thecontrolcentre** » Mon Aug 28, 2023 10:05 pm

kritikon wrote: Sun Aug 27, 2023 1:44 am
Mode Name Recommended Cable Length Bandwidth
USB 1.1 (Full Speed) 3 m (9 ft) 12 Mbps
USB 2.0 (High Speed) 5 m (16 ft) 480 Mbps
USB 3.2 Gen 1 2–3 m (6–9 ft) 5 Gbps
USB 3.2 Gen 2 3 m (9 ft) 10 Gbps
USB 3.2 Gen 2x2 (USB-C) 3 m (9 ft) 20 Gbps
USB4 (USB-C) 0.8 m (31 in) 40 Gbps

That's some useful information there ... thanks kritikon

muki · Post by **muki** » Thu Aug 31, 2023 3:33 am

i had something alike some years ago (a G5 - usb- network ethernet and several mac minis)
what helped was a socalled "NF suppression filter"

https://www.google.com/search?q=NF+supp ... UTF-8#ip=1

michat · Post by **michat** » Tue Sep 12, 2023 7:00 pm

Hey guys, sorry for the late reply and thank you all for your help. It's the USB indeed. As soon as I unplug one of the Synthesizers, the noise is gone. Sooooo..... next project will be climbing into the chaos and hooking MIDI up for all devices involved

vurt · Post by **vurt** » Tue Sep 12, 2023 8:09 pm

glad you found the issue!

thecontrolcentre · Post by **thecontrolcentre** » Tue Sep 12, 2023 9:28 pm

michat wrote: Tue Sep 12, 2023 7:00 pm the noise is gone. Sooooo..... next project will be climbing into the chaos and hooking MIDI up for all devices involved

I'm about to embark on the same journey. I've just finished hooking up all of the audio connections. It's MIDI next

so I picked up one of these ... (and a big pack of MIDI leads)

https://www.ebay.co.uk/itm/144786232475 ... 611bbda4fe

michat · Post by **michat** » Wed Sep 13, 2023 10:02 am

thecontrolcentre wrote: Tue Sep 12, 2023 9:28 pm
I'm about to embark on the same journey. I've just finished hooking up all of the audio connections. It's MIDI next so I picked up one of these ... (and a big pack of MIDI leads)

https://www.ebay.co.uk/itm/144786232475 ... 611bbda4fe

Hmmm, never seen this one before, looks interesting.
Seems to be UK only, 20€ just for shipping to Germany

10 kHz noise / spike when recording synthesizers