Sample editor that can precisely trim silence bellow -120dB+?

[SeeingInMidi]

I'm looking for an editor that can batch trim front and back, silence from a file with a threshold that can go below -120dB or even more. I've tried many editors already, can't seem to find one that has a threshold that goes this low.

[JeffLearman]

Just curious, why do you want to do this? Note that a 24-bit converter only converts 20 bits of actual audio signal; the lower 4 bits are random. These random bits are very useful in avoiding artefacts caused by digital processing. Those lower 4 bits of noise amount to a -120 dB noise floor. That is, if you recorded absolute silence fed into an ideal 24-bit recorder, the result would have -120 dBFS level of pure white noise. (Maybe the noise isn't white; I'm guessing that the numbers are evenly distributed random.)

So, -120 dBFS is the closest thing you'll ever get to silence from a 24-bit converter that's working perfectly. Why do your files have below this level, and why do you want to discriminate between levels that are so low?

[JeffLearman]

As an analogy about why we want the 4 bits of noise at the bottom, here's something I learned from a fried who designed image processing for medical instruments. At that time the cameras were "12-bit" converters, but the bottom two bits were noise, so only 10 significant bits. The reason they added the two noise bits was to avoid things called "mach bands," which were obvious and annoying in the resulting images when using 10-bit converters with no noise added.

See https://en.wikipedia.org/wiki/Mach_bands and look at the pictures.

Adding the two bits of noise dramatically reduced this effect. Similarly, adding noise to the bottom of an audio signal reduces annoying noisy-sounding results from certain kinds of signal processing. Note that while the cause for mach bands is attributed by Google to human visual processing (which is true), even if we didn't have such special processing, there would still be noticeable bands, and adding noise would reduce how noticeable the bands are. (It's possible to demonstrate this with a properly prepared image that reverses the human eye filtering effects, but I have neither the math nor the image processing skills to do it.)

Keep in mind that this is just an analogy to help understand why adding noise can help. As with all analogies, there are a number of differences between the cases.

[JeffLearman]

Have you tried sox? https://sox.sourceforge.net/

[sinkmusic]

Just curious, why do you want to do this?

I was genuinely curious about the same thing... Maybe the OP wants to trim a file which was generated and processed purely in the box (not a recording from a soundcard)?
Thank you for the technical answer, JeffLearman

[SeeingInMidi]

Just curious, why do you want to do this?

I was genuinely curious about the same thing... Maybe the OP wants to trim a file which was generated and processed purely in the box (not a recording from a soundcard)?
Thank you for the technical answer, JeffLearman

This is exactly why. I'm creating files at 32 bit float and would like to keep as much of the noise floor as possible and remove whatever silence that is bellow -120dB or more.

[SeeingInMidi]

Have you tried sox? https://sox.sourceforge.net/

Thanks for the explanation above. I'm working with 32bit float files. I'll try out sox.

[SeeingInMidi]

Deleted. Double post

[HAL76]

Take a look at the free noisetime silrem http://www.noisetime.com/silrem.html
I use it all the time.

[JeffLearman]

Just curious, why do you want to do this?

I was genuinely curious about the same thing... Maybe the OP wants to trim a file which was generated and processed purely in the box (not a recording from a soundcard)?
Thank you for the technical answer, JeffLearman

This is exactly why. I'm creating files at 32 bit float and would like to keep as much of the noise floor as possible and remove whatever silence that is bellow -120dB or more.

You're not losing any meaningful dynamic range or noise trimming to -12dB. So, good luck, but practically (and even theoretically, to some extent) speaking, you're chasing something that isn't going to make a difference. But it's your right to try!