So this KeyStep I just got seems to pick up all kinds of noise when the USB cable is plugged into the computer (or a hub connected to the computer). If I power it using the USB cable plugged into a powered hub not connected to the computer it’s fine, it’s quiet. Has anyone else seen this?
Did the Keystep come with the ground loop remover thingie like the Beatstep Pro does?
It’s a splitter that allows 1 to go to USB (PC) and the other side to go to Power to remove any kind of Ground Loop that causes noise and issues.
Or I might not know wtf im talking about… it’s 4/20 after all… lol
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Nope, just comes with a USB cable with ferrite blob on it.
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gotcha, hmm, are there any kind of Arturia Forums as well?
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Now when you say it picks up all kinds of noise, do you mean that the midi/cv signals are dropping or something? When I first got my BSP I remember almost the opposite being true because I was using a crappy USB power solution and the CV was flaking. I’ve never had any issues with it directly out of the Mac Mini or the old MacBook so long as it’s plugged into the charger. If you’re running off of battery I would expect problems. What is your system (HW/SW) setup that you’re seeing it? I’ve never had any trouble using a BSP, KSP or Keystep directly powered off of the USB line into the DAW/VST hosts though.
I have a support ticket open but thought I’d ask here.
Just discovered it’s quiet if I plug USB into my Chromebook. I guess I could try the Mac in the basement too, have to move the Mother-32 though. So it could be my desktop machine’s to blame — doesn’t affect my USB powered sound interface though.
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No MIDI involved here, this is just the KeyStep CV and gate plugged into my synth (either the modules or the Mother-32). Noise is erratic high pitched sounds on the synth output. Computer is a desktop machine.
If you really need to run it off of the machine with the problematic port, you could get a hub with external power (something rated for iPad charging) to boost the power might do the trick.
Nope, tried that. This post probably needs more characters.
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I never notice any noise coming from my keystep. Sorry i wish i could help you.
I fixed the thread title though!
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Yeah, I tried it with the old Mac downstairs. No noise there either. Just the one computer I’d really LIKE it to work with.
Hmm, or maybe something else plugged into that computer’s USB?..
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Got it. It’s the USB sound interface. When that’s not plugged in on the same computer, the KeyStep’s happy.
Sheesh.
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Could it be due to improper grounding?
My understanding is that the problem occurs when you have the USB audio interface and the KeyStep plugged in the same computer’s USB ports and, I am assuming, also plugged in the same audio mixer (or similar audio equipment).
That would form some kind of loop as USB is not isolated like MIDI is.
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Setup is KeyStep and audio interface both plugged into computer USB, KeyStep gate and CV plugged into synth, synth into audio interface, listening on phones plugged into audio interface.
If I unplug gate and CV from the synth, or synth from the audio interface, the noise goes away.
If I power either the KeyStep or the audio interface from the laptop, the noise goes away. If I power both from the laptop, it comes back.
On further investigation, if I change the synth’s output level the noise level doesn’t change. If I change the interface’s input level, the noise level changes. So the noise seems to originate somewhere between those points.
Very weird. Noise always is.
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Pretty definitely some kind of grounding thing, I think. Normally the audio interface gets its input from the Mother-32, which serves via its external audio in as an output for the modules as well. I’ve tried connecting it instead to the mixer module, with no connections from the Mother-32 to any modules and no inputs to the mixer. (Also, I’m using a different cable this time.) As soon as I plug the KeyStep CV into an oscillator module — also not connected to anything else — the noise reappears. Again the level has nothing to do with the mixer output level though it does vary with the interface input level. The only connections between the mixer and the oscillator are the power rails and ground.
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Does it happen with the laptop running on battery?
Does the laptop have a fig-8 or mickymouse mains cable?
If its ok on battery and the laptop has a Micky… Then you may need to replug the mains lead removing the earth.
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Sounds like you’ve got a ground loop there ! That makes the noise. This is very annoying / struggling with a similar issue, because it is hard to break the loop. I’ve tried a USB isolator between my laptop and audio interface and unfortunately that resulted in stuttering audio because the USB isolator’s bandwidth is too small ( it can not provide the data at the rate the interface wants to get data fed into it). On the other hand I’ve had some limited succes adding a USB isolator between the laptop and the midi-interface (which isn’t as demanding in terms of data throughput of the USB isolator).
Probably the wisest is to NOT use USB in your equipment (is difficult to achieve these days without loosing a lot of functionality ) OR to decouple on the analog side.
B.t.w. Loopop has a video on this topic:
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Thanks, I was planning on looking into USB isolators. But maybe optoisolators between the KeyStep and the synth would be better.
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Do you have a 9V supply you could test with? (9V DC, 500 mA, center positive). I think it pulls the power from that one, if both are plugged in.
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9V supply is an improvement but still not good. There’s actually two distinct components to the noise, high and low frequency. The high frequency goes away when using the 9V supply, but not the low.
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