Sample auditioning, var. delay zippering noise, clocked delay bug

can we have a global volume setting for sample auditioning? i almost lost my hearing yesterday when i accidentally clicked on the loudspeaker symbol on a single cycle waveform during a quiet and delicate feedback patch (output was very high to hear all the details) …

and i have strange noises when modulating delay time on the var delay unit, even when modulated only a tiny amount.

and on the clocked delay i had strange short sample reduction sounds, it sounded as if the clock input couldn’t track the incoming clock all the time, even though the clock was a very stable pulse. i then changed to an internal clock and the noise vanished.

Does this help with modulating the delay?

no, i first thought that changing the tracking, slew might help, but it doesn’t. it’s not a noise you would expect by modulating delay time, it’s veeery fine and i only clearly hear it on headphones, a bit like the sound you hear when loading a sample into the pool, eg when you see the sd card led flashing…

You might be experiencing something similar to this:

The clocked delay doesn’t play nicely with external clock sources. Any clock-to-clock jitter produces warbling in the delay output due to instantaneous changes in the delay time. I’ve taken to using the fixed delay and manually calculating the time for tempo-synced delays.

thanks @miminashi that’s probably what i experienced with the clocked delay unit. however i didn’t hear warble but a distinct sample reduction noise every so often, bright aliasing sounds.

Hmm but would that have prevented the accident? You would still have had to remember to set this global volume to an unusually low setting to compensate for your unusually high gain situation.

May I ask for a short recording using the 6-track recorder and a description of the modulation signal? The internal recording is important because it will identify if this “noise” that you are hearing is actually generated inside the ER-301 or outside of it.

For example, amonst other things, I just tried feeding a 135Hz Sine into a Variable Delay with its delay modulated by 3Hz Triangle from 198ms to 202ms and I couldn’t get any “strange noises”:


Oops this one fell through the cracks. It’s on the bug list now.

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Here too, an internal recording of these “strange short sample reduction sounds” would be highly appreciated!

yes, you’re right, it wouldn’t have prevented the accident, but still, auditioning single cycle waveforms for example is something you might wanna do during a patch and then it would be good to have an option to change the volume, but maybe it’s just a matter of experience and setting the output module accordingly!

ok, here is the first recording of the noises i hear when modulating the variable delay unit, i have it 100% wet and both channels have a fast lfo sine wave modulating the time, i changed the tracking but that doesn’t have an effect. the modulation index is very very low, 0.04 approximately and i change it a bit during recording. i recorded with the 6track recorder and made it louder on the computer:


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and here’s a short recording of this clocked delay noise, again, recorded internally and boosted on the computer. clock is coming from a 4ms rcd which itself receives a pulse from a vco-2rm as clock. 3 voice sine waves.

it’s also clearly visible in this spectrogram:

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These help a lot @kilchhofer! I think I know the problem with the Variable Delay. For my reference, what was the frequency of the delay modulation?

Still analyzing the Clocked Delay artifacts…

hm, i don’t remember exactly, but around 17Hz. another observation i just made is, that i hear some very fine click like artefacts even when the modulation index is zero, when i set the volume of the modulator sinewave to zero these sounds vanish. the harsher noises come in when mod. index is 0.002 and then fine steps upwards 0.004 etc until about 0.020 or so the noise is “stable” and doesnt change much. but there is also this distinct high beep around 12kHz.
here another short recording, this time only on the right channel:

and the spectrogram:

one can see when the clicking starts (mod.index still at 0) and then all the artifacts until these stop but the high signal which is also visible but not audible on the left channel gets louder (the 12kHz line).

and an update on the clocked delay noise. i changed setup a bit and had the vco-2rm pulse go directly into the 301 without clock divider in between. the slightest touch on the clocks frequency makes these artifacts, if i don’t touch it at all then i don’t have the sample rate reduction sounds but the occasional warble when the clock “updates” as described by @miminashi.
i then tested this internally, put a sine wave on channel four, squared it with a limiter and routed this to my clock input internally, everything works fine until i change the clocks frequency just a tiny amount.
so my guess is that the 4ms rcd introduces more fluctuations to the clock. without it and without touching the clocks frequency i don’t hear these aliasing sounds but the occasional warble when the clock updates itself.

Are you running the most recent firmware? v0.2.9

yes, 48kHz