Old 12-27-2019, 02:06 PM   #1
ajmich
Human being with feelings
 
ajmich's Avatar
 
Join Date: Aug 2013
Location: N.E. Michigan
Posts: 14
Default High-pitched noise in audio on iMac Pro 2017

Experiencing an annoying high-pitched noise in the audio of an iMac Pro (2017) using Reaper current version -- NOT physical noise such as a fan, etc. The noise winds up on any recordings made.

OS and all software up to date. Have removed all external gear, drives, etc., in attempting to pinpoint the source, leaving only the internal SSD drive running. The noise volume is low but constant, unaffected by any level settings.

Along with the tone is random sharp clicking, sounding much like a typewriter. WTF!?

Anyone have any ideas as to source and how to get rid of it?

The attached zip contains a 10-second sample of the noise. TURN YOUR AUDIO DOWN before playing as the file is recorded at high volume. The actual noise is probably 40dB down or more, very low but quite obvious during soft music or between tracks.
Attached Files
File Type: zip mac-noise-10sec.mp3.zip (102.0 KB, 19 views)
__________________
Cheers...... Alex

Last edited by ajmich; 12-27-2019 at 07:30 PM. Reason: Attached file containing audio sample
ajmich is offline   Reply With Quote
Old 12-29-2019, 11:23 AM   #2
Ideosound
Human being with feelings
 
Ideosound's Avatar
 
Join Date: Oct 2017
Location: U.K
Posts: 188
Default

Are you using a usb audio interface?
Ideosound is offline   Reply With Quote
Old 12-29-2019, 11:27 AM   #3
ajmich
Human being with feelings
 
ajmich's Avatar
 
Join Date: Aug 2013
Location: N.E. Michigan
Posts: 14
Default

Quote:
Originally Posted by Ideosound View Post
Are you using a usb audio interface?
Yes, but tested with no USB connections, noise still present.

My interface is the Audioquest Dragonfly Cobalt.
__________________
Cheers...... Alex
ajmich is offline   Reply With Quote
Old 01-02-2020, 11:10 PM   #4
Aymara
Human being with feelings
 
Aymara's Avatar
 
Join Date: Dec 2014
Location: Ruhr Area, Germany
Posts: 974
Default

It seems, this discussion should continue here?

https://forum.cockos.com/showthread.php?t=223551

Did you try a different audio interface in the meantime? I have absolutely no issues with my iMac Pro and a Thunderbolt Quantum 2 by Presonus.
__________________
Greetings from Germany

Chris
Aymara is offline   Reply With Quote
Old 01-03-2020, 06:55 AM   #5
vdubreeze
Human being with feelings
 
vdubreeze's Avatar
 
Join Date: Jul 2011
Location: Brooklyn
Posts: 1,884
Default

Weird Clicking comes in different flavors, usually makes one think of mechanical drive failing or clocking mismatch, but that typewriter thing? Hmmmm? And after careful repeated listening and consulting with experts...that definitely is a squeal

I would say boot as another user to see if the OS X sound prefs got hosed. Barring that, go into the user library (make it visible by holding option while going to Go menu) and remove any Apple sound or audio preferences, and move the whole plugins folder to the desktop so it boots without any plugins.

Maybe something in the Reaper routing is causing it to feedback? If you don't have a alternate user to boot as, create one in the Users And Groups System Prefs from the left menu, and allow it to be an admin. This will create a new Reaper setup from default as well as for Apple, and also of the interface software, if it has any.
__________________
The reason rain dances work is because they don't stop dancing until it rains.
vdubreeze is offline   Reply With Quote
Old 01-04-2020, 10:08 AM   #6
Ideosound
Human being with feelings
 
Ideosound's Avatar
 
Join Date: Oct 2017
Location: U.K
Posts: 188
Default

Quote:
Originally Posted by ajmich View Post
Yes, but tested with no USB connections, noise still present.

My interface is the Audioquest Dragonfly Cobalt.
I'd heard the security T2 chip was causing some issues with USB interfaces, that was why I asked...
Ideosound is offline   Reply With Quote
Old 01-04-2020, 10:35 PM   #7
ajmich
Human being with feelings
 
ajmich's Avatar
 
Join Date: Aug 2013
Location: N.E. Michigan
Posts: 14
Default

Quote:
Originally Posted by vdubreeze View Post
...And after careful repeated listening and consulting with experts...that definitely is a squeal I would say boot as another user....
Thanks, enjoyed your response; I do need to laugh about this damned thing, it is such a headache! Audioquest (actually, their designer of the Dragonfly DAC) says,

"The clicking is the asynchronous feedback not working. The 2, 3, 4Khz tone I have no idea. We don't have anyone else experiencing that. If you can dig up a copy of HALLab from Apple you can look around there and see if something is doing anything to cause these problems. Or open the Terminal in the Utilities folder and run top and see if there are any processes that seem out of the ordinary."

Hmmm, well.......... I chased 'HALLab' down a dark alley to nowhere, and 'top' revealed a huge number of processes that I cannot really interpret at my pay grade, but none of those running seemed suspect.

The alternate user idea looked promising, but ultimately resulted in the same issue -- thanks for trying. Removing those preferences made no difference. And I could not find a plugins folder that contained anything significant [most were empty], although I do have Izotope Ozone plugins in there somewhere.

At this juncture I'm faced with a clean install of Catalina, holding off on the plugins just in case, and testing the system again while fresh. Humph. BUT, pretty much resigned to using the iMac Pro's headphone jack to feed the recorder and skipping the DAC entirely -- as it has been pointed out to me elsewhere (and, pointed-ly), that the audio from the Mac is greatly superior to the vintage circuits in the analog recorder (Otari) that I'm using, so in essence there is no advantage to the DAC anyway, at least with the iMac. Wish I was comfortable with that. Some listening tests would probably be convincing. I have other machines that would benefit from the Dragonfly though, so not a complete waste of money.
__________________
Cheers...... Alex
ajmich is offline   Reply With Quote
Old 01-05-2020, 04:08 AM   #8
Aymara
Human being with feelings
 
Aymara's Avatar
 
Join Date: Dec 2014
Location: Ruhr Area, Germany
Posts: 974
Default

How should a clean install of Catalina help, if you reported in the parallel thread in the general forum, that the Dragonfly has similar issues, when you tested it on a PC?

Why don‘t you use your Steinberg interface to feed the recorder ... it has Line Out, hasn‘t it? And that is a much better choice, than headphone output to feed a recorder.

PS: And why do you use an analog tape recorder at all, when you can record digitally on the iMac Pro and if needed simulate „tape audio“ with plugins?
__________________
Greetings from Germany

Chris

Last edited by Aymara; 01-05-2020 at 04:34 AM.
Aymara is offline   Reply With Quote
Old 01-05-2020, 09:39 PM   #9
ajmich
Human being with feelings
 
ajmich's Avatar
 
Join Date: Aug 2013
Location: N.E. Michigan
Posts: 14
Default

Quote:
Originally Posted by Aymara View Post
How should a clean install of Catalina help
I suppose that a clean install is just a mostly useless, compulsive way to convince myself that there are no additional oddities, remnants, whatever, lingering in the file system. I do clean installs about twice a year anyway. To each his own, yes?

The Steinberg is a fine unit leftover from another setup; I just need to acquire the necessary cables.

Actually you are quite mistaken about the headphone output of the iMac -- it is in fact a multi-purpose audio output and (I am told) is of very high quality. So good, I doubt I even need the DAC at all.

The analog tape is for specific projects having nothing to do with producing a certain tape sound. The choice of recording method has nothing to do with the issue. I simply require analog tape for output of said projects. Not everyone desires everything to be done digitally. Presume much?
__________________
Cheers...... Alex
ajmich is offline   Reply With Quote
Old 01-05-2020, 11:59 PM   #10
Aymara
Human being with feelings
 
Aymara's Avatar
 
Join Date: Dec 2014
Location: Ruhr Area, Germany
Posts: 974
Default

Quote:
Originally Posted by ajmich View Post
The Steinberg is a fine unit leftover from another setup; I just need to acquire the necessary cables.
And that seems to be the fastest and cheapest solution to your problem, because you can use line out.

The headphone jack of the iMac is high quality, yes, but according to Apples’s specs it has the wrong impedance (24 Ohm) to feed the line in of the tape machine, so it‘s a compromise and not an ideal solution.
__________________
Greetings from Germany

Chris
Aymara is offline   Reply With Quote
Old 01-06-2020, 07:14 AM   #11
ajmich
Human being with feelings
 
ajmich's Avatar
 
Join Date: Aug 2013
Location: N.E. Michigan
Posts: 14
Default

Quote:
Originally Posted by Aymara View Post
The headphone jack of the iMac ... has the wrong impedance (24 Ohm) to feed the line in
"Wrong" impedance? I've not had any problem in that regard. It drives the line in just fine!
__________________
Cheers...... Alex
ajmich is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -7. The time now is 10:33 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.