Problem - Noisy Shruthi

Hello all,

Well today I powered my shruthi along with my other synths and while I was recording low notes, I noticed some noise around the sound.
I am pretty sure it did not happen before and it is only when notes are played.
After some testing, it seems that this noise occurs for every notes.

You have to put the volume loud enough to hear it, but added to my reverb and an eq, it is multiplied by 10!
Very unfortunate for clean recordings…

Here is a sound sample of this “problem” (in wav):

noisy Shruthi.wav

Well I have no idea what the problem could be, my shruthi has not moved since more than a month…

Oh and you have to put headphones on to hear it but it is pretty clear at the end of the sound sample…
Anyone? Did somebody already experienced this problem?

I don’t really hear anything too out of the ordinary. Small blips in sound like that can be caused by a few things.
1: The envelope moving too fast for the filter. This can cause clicks an pops before and after notes.
2: The oscillator compensating for aliasing at higher frequencies.
3: You have your synthesizer sitting on/by something with an interfering magnetic field. This could be a powersupply, a radio, or really any other kind of audio/electronic device. make sue that you are using shielded cables as well or the noise may be interference from the wire.

Is this recording you posted exactly how it sounds? Are you sure that your audio recorder did not apply a noise reduction algorithm to it?
This sounds very minimal as far as analogue noise floors go. Every analogue device has a noise floor - it adds to the “analogue” sound.

To really solve your problem, you should make a test tone patch. With this you can test various frequencies for the oscillator and cutoff for the filter, ect. That will help you find what causes the noise to be “worse” or “more noticeable”.

What do you mean by “the envelope to fast for the filter”? Any Filter is as fast as any envelope can do, i think what you mean by klick is explained here under “Q: Why do some synths produce clicks?”

@fcd72: That is exactly what I mean. It can be gotten rid of by increasing the amount of attack time. Or, more technically, by flipping out a few capacitors to slow the envelope’s affect on the filter. That is not necessary in this case.

Thanks guys for your answer!
I have my shruthi sitting in my audio card… I will try it away from every electronic devices and let you know.
I know it is not that much and I like the fact that analog sound is not totally clean but I had the feeling that this did not happen before. My tx81z and r8m do not seem to present this little noise problem so it is not an audio interface or mixer problem.

Yeah, those synths are digital. So no/very quiet noise floor for them. :slight_smile: It is good that you have a solid point of comparison.
One of my smaller, battery powered mixers picks up a lot of interference from other synthesizer’s internal powersupplies, so I need to be careful where I sit it. Good luck trying to fix your problem.