Avid Pro Audio Community

Avid Pro Audio Community

How to Join & Post  •  Community Terms of Use  •  Help Us Help You

Knowledge Base Search  •  Community Search  •  Learn & Support


Avid Home Page

Go Back   Avid Pro Audio Community > Pro Tools Software > Pro Tools 2020

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 10-22-2020, 09:45 AM
EGS's Avatar
EGS EGS is offline
Member
 
Join Date: Nov 2004
Location: Chicago
Posts: 2,827
Default fix distortion in audio restoration project?

Hey all,

I've got an audio restoration gig, consisting of cleaning up several precious old out-of-print classical records. One in particular has brief moments of distortion at loud peaks. It is clean except for these peaks. This is not digital clipping, but rather an analog distortion present on the source. We've even been able to examined more than one (identical) LP pressings, and the distortion is present in the same spots on all.

How to fix?

My best solution - so far - is to use Izotope RX to manually select and lower the gain of the tiny bits of distortion, often working the frequencies in-between the music when possible. Sometimes this kinda sorta works...

Help!
__________________
Desktop: PT 2020.5 / Win 10 / GIGABYTE GA-X58A-UD3R / i7 hex 3.9GHz / 32GB / Focusrite LS56
Laptop: PT 2020.5 / Win 10 / HP ProBook / i7 quad / U-PHORIA UMC1820
Legacy: PT 5 & 6 / OS9 & OSX / Mac G4 / DIGI001
Click for demo
Reply With Quote
  #2  
Old 10-22-2020, 09:52 AM
albee1952 albee1952 is offline
Member
 
Join Date: May 2004
Location: Norwich, CT
Posts: 35,954
Default Re: fix distortion in audio restoration project?

That would have been my suggestion too. Maybe check their website and look for some tutorial videos on that function? Then there are some other plugins that are worth a demo:

https://accusonus.com/products/audio...era-de-clipper

http://www.perfectdeclipper.com/
__________________
Gigabyte X79/intel i7 3930K, 32GB RAM, DIGI003 Rack
https://www.facebook.com/search/top/...0sound%20works


The better I drink...the more I mix.....

BTW, my name is Dave, but most people call me.........................Dave
Reply With Quote
  #3  
Old 10-22-2020, 12:40 PM
EGS's Avatar
EGS EGS is offline
Member
 
Join Date: Nov 2004
Location: Chicago
Posts: 2,827
Default Re: fix distortion in audio restoration project?

Thnx I'll check those out
__________________
Desktop: PT 2020.5 / Win 10 / GIGABYTE GA-X58A-UD3R / i7 hex 3.9GHz / 32GB / Focusrite LS56
Laptop: PT 2020.5 / Win 10 / HP ProBook / i7 quad / U-PHORIA UMC1820
Legacy: PT 5 & 6 / OS9 & OSX / Mac G4 / DIGI001
Click for demo
Reply With Quote
  #4  
Old 10-22-2020, 02:28 PM
daeron80 daeron80 is offline
Member
 
Join Date: Apr 2005
Location: Orlando, Florida, USA
Posts: 3,733
Default Re: fix distortion in audio restoration project?

First, congrats! That's a cool gig.

Second, if the distortion was electronic, that's a tough problem, especially if it was transistor breakup. Almost intractable in some cases. Zoom in to the detailed waveform level and see where the discontinuities lie. If they're restricted to the high amplitude portion of the waveform, that's easier to deal with. If they lie along the ramp up or down, several dB below the peaks, then digging out between the overtones may be the best strategy.

If it was mechanical distortion during pressing, which is more similar to clipping, that can sometimes be moderated with the De-clip module of RX. Zoom in and adjust the threshold until it's catching most of the discontinuities. You'll lose some high end detail, but it can be an overall improvement.

Don't forget to try Interpolate and the various Spectral Repair modes. Sometimes they'll surprise you.
__________________
David J. Finnamore

Nyquist was right.

PT 2020.11.0 Ultimate | Omni | macOS Mojave
PT 2020.9.1 | Saffire Pro 40 | Win10
Reply With Quote
  #5  
Old 10-23-2020, 05:55 AM
musicman691 musicman691 is offline
Member
 
Join Date: Dec 2009
Location: The Soprano State (NJ)
Posts: 17,758
Default Re: fix distortion in audio restoration project?

Quote:
Originally Posted by daeron80 View Post
First, congrats! That's a cool gig.

Second, if the distortion was electronic, that's a tough problem, especially if it was transistor breakup. Almost intractable in some cases. Zoom in to the detailed waveform level and see where the discontinuities lie. If they're restricted to the high amplitude portion of the waveform, that's easier to deal with. If they lie along the ramp up or down, several dB below the peaks, then digging out between the overtones may be the best strategy.

If it was mechanical distortion during pressing, which is more similar to clipping, that can sometimes be moderated with the De-clip module of RX. Zoom in and adjust the threshold until it's catching most of the discontinuities. You'll lose some high end detail, but it can be an overall improvement.

Don't forget to try Interpolate and the various Spectral Repair modes. Sometimes they'll surprise you.
I've done vinyl restoration on and off for over a decade using various tools and RX is pure genius with the modules it has. Well worth the money & time spent with it. Is the distortion in one or both channels? If only one channel try bringing audio from the non-distorted channel (if the vinyl is stereo).

Something to think about is it might just be an instrument or instruments played a bit too forcefully and they just got blatty. Or a mic just got overdriven (thinking ribbon mic here).
__________________
Jack
See profile for system details
iMac dead & retired as of 11/4/17

QAPLA!
Reply With Quote
  #6  
Old 10-23-2020, 10:52 AM
itsjustmeee123 itsjustmeee123 is offline
Member
 
Join Date: Oct 2013
Location: california
Posts: 75
Default Re: fix distortion in audio restoration project?

Question... how does RX do with clipped vocals? I have a project where the singer is recording remotely from her home and sometimes the vocal files she sends me are squared off at the top and there’s various degrees of distortion in the louder parts.
Reply With Quote
  #7  
Old 10-23-2020, 01:52 PM
originalscottyg originalscottyg is offline
Member
 
Join Date: Jan 2006
Location: Detroit
Posts: 725
Default Re: fix distortion in audio restoration project?

Quote:
Originally Posted by itsjustmeee123 View Post
Question... how does RX do with clipped vocals? I have a project where the singer is recording remotely from her home and sometimes the vocal files she sends me are squared off at the top and there’s various degrees of distortion in the louder parts.
RX De-clip module pretty hit or miss for me. Sometimes I am amazed with the results, and sometimes no matter what I do it only sounds the same or worse. It really depends on the source material, and it definitely requires a lot of trial and error with adjusting settings and re-rendering (from the raw audio). Anything that is severely distorted will never sound pristine, but De-Clip can improve things, sometimes significantly, many times marginally.
__________________
Scott Gatteño
Yessian
Reply With Quote
  #8  
Old 10-23-2020, 02:12 PM
musicman691 musicman691 is offline
Member
 
Join Date: Dec 2009
Location: The Soprano State (NJ)
Posts: 17,758
Default Re: fix distortion in audio restoration project?

Quote:
Originally Posted by originalscottyg View Post
RX De-clip module pretty hit or miss for me. Sometimes I am amazed with the results, and sometimes no matter what I do it only sounds the same or worse. It really depends on the source material, and it definitely requires a lot of trial and error with adjusting settings and re-rendering (from the raw audio). Anything that is severely distorted will never sound pristine, but De-Clip can improve things, sometimes significantly, many times marginally.
The secret with a lot of rescue work in RX is to do things a little at a time; don't try and fix it in one pass.
__________________
Jack
See profile for system details
iMac dead & retired as of 11/4/17

QAPLA!
Reply With Quote
  #9  
Old 10-23-2020, 04:03 PM
seanmccoy seanmccoy is offline
Member
 
Join Date: Aug 2007
Location: Southern Oregon
Posts: 525
Default Re: fix distortion in audio restoration project?

Quote:
Originally Posted by originalscottyg View Post
RX De-clip module pretty hit or miss for me. Sometimes I am amazed with the results, and sometimes no matter what I do it only sounds the same or worse. It really depends on the source material, and it definitely requires a lot of trial and error with adjusting settings and re-rendering (from the raw audio). Anything that is severely distorted will never sound pristine, but De-Clip can improve things, sometimes significantly, many times marginally.
My experience exactly. It's occasionally jaw-dropping, usually an improvement, and a total fail only once in a while. Clearly it depends on the nature and severity of the distortion. But overall I've definitely had more successes than disappointments.
__________________
ADK Core i7 4.20, 32GB RAM, W10 Pro, PT HD 2020.9.1, HD Native, OMNI, Digi 192, AJA Kona LHi, UAD-2 Octo; Mac Pro 12-core 3.46, 64GB RAM, Mojave, Logic Pro 10.5.1, Apogee Rosetta 800, UAD-2 Quad, MOTU 2408 Mk II: MBP mid-2012, 16GB RAM, Mojave, MOTU 8-Pre-ES, Pro Tools 2019.10
Reply With Quote
  #10  
Old 10-26-2020, 08:35 AM
daeron80 daeron80 is offline
Member
 
Join Date: Apr 2005
Location: Orlando, Florida, USA
Posts: 3,733
Default Re: fix distortion in audio restoration project?

Quote:
Originally Posted by musicman691 View Post
The secret with a lot of rescue work in RX is to do things a little at a time; don't try and fix it in one pass.
Bingo.
__________________
David J. Finnamore

Nyquist was right.

PT 2020.11.0 Ultimate | Omni | macOS Mojave
PT 2020.9.1 | Saffire Pro 40 | Win10
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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

Similar Threads
Thread Thread Starter Forum Replies Last Post
HELP! M-Audio Project Mix+Intel Quad6600+PTMP7.3=Distortion! RICKSTER7 Pro Tools M-Powered (Win) 17 10-07-2019 10:09 PM
Restoration of bad audio Postman Post - Surround - Video 11 06-24-2015 01:19 PM
Audio restoration plug-in garimpo Post - Surround - Video 5 06-14-2008 07:20 PM
Audio restoration.... assemblyworker Tips & Tricks 5 06-19-2007 10:21 AM
restoration project woes trexonbass 003, Mbox 2, Digi 002, original Mbox, Digi 001 (Mac) 1 01-17-2006 02:04 PM


All times are GMT -7. The time now is 11:13 PM.


Powered by: vBulletin, Copyright ©2000 - 2008, Jelsoft Enterprises Limited. Forum Hosted By: URLJet.com