OWL pops

OWL
#1

I did some test with the latest patch for Rev04-004 to eliminate digital artefacts. The patch works great but there are still some minor issues. At least with my unit.
If you listen closely to the patches in a silent room and or with headphones on you can hear some kind of low end pops after each note. The example i created is done with the Faust/SmoothDelay preset but you can use any preset. Even a test preset with no knob readings and no processing creates these pops. The pops appear shortly after the attack.
Owl_pops

#2

Hi Stiwi,

I had a look at the waveforms of your audio file. It seems that your input is clipping slightly. Have a look at the second or third oscillation after the attack, when not in Bypass.

Did you try different sensitivity settings on the OWL ?

Thanks
Giom

#3

Thanks giom. I am on vacation right now. I’ll check the input settings next week when I am back.

#4

I am back an did some more tests. It seems that the low end noise (pops) after each note has something to do with the usb connection. See this video.


00:03-00:13 - | USB | POWER | LOW  | BYPASS | -> POPS
00:18-00:27 - | USB | POWER | HIGH | BYPASS | -> POPS
00:31-00:40 - | USB | POWER | LOW  | BYPASS | -> POPS
00:45-00:55 - | USB | POWER | LOW  | EFFECT | -> POPS
00:59-01:10 - | --- | POWER | LOW  | EFFECT | -> OK

I disconnected the usb port at 00:59 and the popping (and some noise) disappeared.
I added two more test (not related to the pops) to show the overall difference in sound between effect and bypass. The effect part is missing a lot of the high-mids.


01:11-01:18 - | --- | POWER | LOW  | EFFECT | -> Frequency rolloff at about 2kHz.
01:21-01:28 - | --- | POWER | LOW  | BYPASS | -> Frequency response OK
#5

I did a test with white noise and sine sweeps and the frequency response is ok. So forget the ‘difference in sound between effect and bypass’ stuff. I must admit that this had something to do with my audio interface input settings. (Impedance-matching)

#6

Interesting. Were you using a line level input? The output impedance of the pedal is about 100 Ohm, which is low enough to drive almost all inputs but doesn’t work well with most headphones - you lose high end and clarity.

#7

@mars If i use the line level input of my audio interface the owl effect and bypass sound is identical. Only if i use the instrument input the owl effect sound loses high end and clarity.

@giom Could you verify the pops with usb connection? post-1710

#8

Interesting indeed !
Will do my best but I am away until the end of August and have limited test equipment with me (only an OWL and a pair of headphones, not great)…

It is clearly not due to sensitivity.

What strucks me in your post 1710 is that the pops appear when both USB and External Power are applied. I usually use one or the other.

External Power only → OK
USB only → could you try this one in the meantime ?

Will try to replicate on my side as well.

Giom

#9

I did forget to unplug the external power supply in the first test. Sorry. But the result is the same. Here is a video with the OWL connected to usb / macbook only. Guitar to Owl left in, Owl left out to audio interface. The interesting part here is that the pops are audible both in effect and bypass mode.


00:00 - 00:20 -> effect
00:20 - 00:40 -> bypass

Owl_pops_usb

#10

I was wondering if this issue is solved or not? Is it a problem with this particular unit or is it a problem with every unit?