Noise / White noise background noise on rev2 Programs

[justincarter]

Hey everyone,

I recently got a new rev2 and loved it until today (well i still love it) but i'm a bit concerned. I've had it about 2 weeks now and I don't know if it was always there and i was oblivious to it but today i noticed on some programs i hear very visible white noise or background noise both from the main a outs and more noticeably on the headphone out of a pair of beyer dynamic dt770 pros?

I'm uploading a sample of some presets from Creative Spirals packs which many seem to have (no shade here, they still sound amazing!!)

in random order on the audio sample:
The programs sampled are: Holiday, Ambipluck, Everything3, Yorkey, the last bit is an amplified example of a preset not in use but the background noise when nothing is happening. 

Is a little background noise like this normal on analog synths?  I want to say it could be my cables, but it's the same issue on 3 pairs of cables so i don't know.

I'm using Hosa unbalanced TS cables and a Hosa TRS to unbalanced TS cable in the headphone jack along with my headphones.

When I used the headphones it's the noisiest.  I might also mention that i do have the volume turned up all the way but it still happens at low volumes when i add gain to the recorded track.

Any thoughts or recommendations?

Thanks,
justin

[Autosynther]

Check if those presets have Distortion effect, it has a lot of noise.
- hold Misc button and turn Effect select to effect used or just turn effect off for a bit

Preset F1 67 "Can't kill me" has Dist effect and everything on max regarding parameters, 100% wet, 127 on param1 and 2 etc. Sound like an ocean in background.

I could not reproduce any other way, not from basic program and increase release time on amp or any other way.

[Manbird]

Is the synth connected to your computer via USB cable? USB noise is a not uncommon problem...

[justincarter]

Hey Autosynther

Thanks for the response, i checked out the Factory program you suggested and removing the distortion helped on that and a couple of the others i did in my original post.

This being said, last night i was all over the place and in panicky mode.

The noise is definitely more prominent coming from headphones when the volume is cranked
The noise is less noticeable when plugged into my MotuM6


I made some new recordings with just factory programs to see if anyone had any suggestions about what I'm hearing or to see if anyone might be willing to compare these sounds to yours? (Any help Appreciated!)

When making these recordings straight into my M6 with Hosa unbalanced cables (unplugged all midi cables and usb), all mics, and harddrives, and turned off the lights)

1. F1P1 - LosVangelis - sounds perfectly fine to me
2. F1P2 All That Glitter - sounds good when the sound plays but you'll notice before i press there's a faint white noise with what sounds like interference or like faint radio signals - or maybe i'm going crazy?)
3. F1P4 Balalaika2017 - same as above
4. F1P4 Balalaika2017 - with no notes played
5. F1P67 Cant Kill Me w/wo (the program you mentioned to test, definitely removing distortion helped, this one i don't actually mind the noise haha) the part at the end is with distortion off.

To me the confusing part is the interference? or is just what to expect in these programs when a note isn't being played, if that's the case, fine, but just really want to make sure the the volume knob isn't defective or causing the issue

I've also noticed if i adjust the LPF Cutoff - this sometimes helps the noises go away.... (is this weird?)

Should I try calibrating?  I have tried already but it always get stuck on OSC2 and won't complete without me having to turn off?

I'll also reach out to Sequential on this regard but maybe a full calibration will do the trick?

As always any help or feedback appreciated.

Thanks!
Justin

Check if those presets have Distortion effect, it has a lot of noise.
- hold Misc button and turn Effect select to effect used or just turn effect off for a bit

Preset F1 67 "Can't kill me" has Dist effect and everything on max regarding parameters, 100% wet, 127 on param1 and 2 etc. Sound like an ocean in background.

I could not reproduce any other way, not from basic program and increase release time on amp or any other way.

[justincarter]

Hey Manbird!  I did / do indeed use a USB for midi, but unplugged when troubleshooting.  Thanks for the suggestion.

Is the synth connected to your computer via USB cable? USB noise is a not uncommon problem...

[Autosynther]

Try calibration
- if it hangs do a global reset first
- I had some issue it hanging when mine was new too

Note one thing about volume knob on REV2
- it sends CC7 for midi volume
- and also receives on CC7 if sequencer send it
- this can mean volume trouble if not aware of it

You mentioned increasing gain in daw, not sure what you meant?
- some daws have fader for midi volume like Cakewalk/Sonar
- if you touch that REV2 will adjust it's volume and not be ackording to knob anymore
- not so fond of this implementation myself, no other synth does this

[Autosynther]

My normal setting making presets and playing outside daw
- volume knob on half(12 o'clock) on REV2
- unity gain on mackie mixer line inputs
- meter hitting about 0 dB playing

Playing presets at 120-127 volume set in misc menu on preset I hear no noise.
- and volume is comfy, not low, just normal comfy

If turning volume on REV2 all the way up, there is quite a bit of noise, but actually playing would be silly loud and ears hurt if doing that for a while.
- meters on mackie would peak at +14 dB and there around
- making a basic program in this setting you hear noise in background all the time also
- but really piercing ear if to play a note
- if I set volume on preset to about 80 noise is basically gone
- so gain on preset plus master volume act together

Set knob for volume on REV2 at noon, and adjust on interface and I wonder if you ever encounter excessive noise.
- and watch out for doing CC7 on sequencer that is send to REV2 it will make it noisy in the same way turning that up physically to max

Unless your machine deviate a lot from this I don't think anything wrong regarding this.

In the early years with 16 bit recording on hdd portastudios I had to keep peaks up close to 0 dB. But with 24 bit recording no need, and don't bother above - 12 dB peaks or so. You don't loose resolution with 24-bit in the same way.

[Autosynther]

I did a test on F1P4 preset
- SNR is -66 dB
- noise floor at -74.3 dB when peak playing is -8.5 dB
- just holding a C-chord playing

I did with volume both on noon, and full, adjusting interface so about -8 dB peaks.
- result is there -65 to - 70 dB SNR
- so nothing wrong with electronics in REV2

Which is more than acceptable. So about which SPL you have listening it seems to me.

[justincarter]

Hey Autosynther,

Thank you so much for your help looking into this.

I was able to successfully do the Calibration based on the instructions above.

I played around all day yesterday and came to the same conclusion as you at the end of the day

When in headphones I was at like 4PM - I know i know - too loud.

Same with the Main audio outs

I turned the volume down and everything is much better.  I'm not sure what I was thinking really.
 
Again, I really appreciate the help and investigating here and sad to say it boiled down to me being not very smart or nice to my ears.

Thank you.

I did a test on F1P4 preset
- SNR is -66 dB
- noise floor at -74.3 dB when peak playing is -8.5 dB
- just holding a C-chord playing

I did with volume both on noon, and full, adjusting interface so about -8 dB peaks.
- result is there -65 to - 70 dB SNR
- so nothing wrong with electronics in REV2

Which is more than acceptable. So about which SPL you have listening it seems to me.

[Autosynther]

Glad to hear it. Hope you enjoy this amazing heritage of Dave Smith as all of us.

[ttaneff]

Had the same issue recently, and I found this thread, just after I managed to solve it... what are the odds!
Your recordings sound exactly what I had (digital aliasing noise, related to modulation), but mine was at a higher audible level.

Support were very nice, confirmed that it is hardware related, gave me pointers how to proceed and where to send my unit (out-of-waranty), but instead I took a risk of fixing it myself...
After some colateral damage and unnecessarily replaced components - it boils down to a single failed capacitor.

If the noise gets progressively worse - look into replacing or bridging capacitor C200 on the mainboard (middle bottom), with a 800-1000nF cap, rated 10V or above. I will not get into technical details, but "Trust me, I'm an engineer"... who lost 4 weeks chasing that ghost noise...

P.S. Attached audio sample at it's worst, before fixing the problem, for reference.

[BT]

Or rather, please contact support first.