Audio restoration: "spectral delete" function is gone

Hello everybody,

my name is Bernard and I´m restoring old sound recordings (mostly ‘spoken letters’ sent over the iron curtain between Poland and Germany on compact cassettes in the 1970’s and 80’s). I have some experience in doing this, including mechanical and chemical work on the rotten tapes and tricks like playing deteriorated tapes with their backsides in contact to the playback heads to avoid the iron layer being planed off, or coating brittle tape in laquer, “baking” tape in the oven a.s.o.

I prefer doing software restorations by hand rather than using automated tools. My favourite method is viewing at the spectrograms and deleting resonances or imperfections by attenuating or amplifying selected portions of the spectrogram. Once you’ve got a trained eye, you can identify the spectral patterns of recording room resonances, jump to the harmonics of the room´s fundamental frequencies and attenuate them.

In my old version of Audacity on my 2007 iMac, I could apply the ‘attenuate/amplify’ filter and modify the selected spectrogram regions by a desired number of dB.

I paused the job for a year or so, but now, with my rather new Macbook and Audacity 2.1.1., the attenuation filter always applies to the whole spectrum. Even worse, the “spectral delete” - effect seems to have disappeared!

I am angry as f… about myself being too stupid to find the missing filters and settings. Could you please tell me if I´m already suffering from dementia, or if those useful features have been secretly removed from Audacity?

Best regards from Germany


The “Spectral Delete” effect was added quite recently. Audacity 2.2.1 is too old.
The current version of Audacity is 2.4.2 which is available via the Audacity website:

If “Spectral Selection” ( is not available, then you may need to enable it in Preferences. See:

  1. Thanks a lot for your answer!
  2. The modern version stopped installing during filecheck procedure, because I use OS 10.12.6 (Sierra), but 10.13 is required. That´s why I installed the 2nd-oldest Audacity version available on the official website, which is `many numbers behind´.
  3. On my 2007 iMac with SnowLeopard (OS X 10.6), i ran some unknown old version of Audacity, and as far as I remember I could apply adjustable attenuation/Filtering (not only deletion) to a spectral selection even then, but I´m not sure anymore.
  4. I´ll pick up my antique iMac from my remote store room to see how it worked. I really don´t remember the version number and exact filter name. Then I´ll make a clone of the old mac with old OS and Audacity on a 2nd partition of my new mac to compare. I´ll report about my findings later!

Thanks sincerely


MacOS 10.07 (Lion) to 10.12 (Sierra) are no longer officially supported, but are believed to work with the > latest Audacity version> .