Could you please help me reverse the volume?

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Winston
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Re: Could you please help me reverse the volume?

Post by Winston » Tue Nov 17, 2020 11:20 am

I did have the idea I could reverse the playback and volume, so it sounds like it is still playing forward with backward notes. When you reverse the playback, the sound that faded out at the end fades in at the end. Similarly, reversing the volume would reverse the fade, but without reversing the notes. Just thought that would be useful in that way, so you don't hear weird, reversed sound while playing in reverse.

How about that? Would something like this be possible in a plugin, or code? (But disincluding reversing playback, I want to reverse the volume in a way that SOUNDS like it is played backward, or rewinding.)

Trebor
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Re: Could you please help me reverse the volume?

Post by Trebor » Tue Nov 17, 2020 2:00 pm

Winston wrote:
Tue Nov 17, 2020 11:20 am
... a plugin, or code? ... reverse the volume in a way that SOUNDS like it is played backward, or rewinding ...
Can reverse the audio in chunks each less than a second long,
see this plugin ... viewtopic.php?p=160165#p160165
Winston wrote:
Tue Nov 17, 2020 11:20 am
... I want to reverse the volume in a way that SOUNDS like it is played backward ...
Possibly reverse-reverb: i.e. reverse, apply reverb, reverse again (so is back the right way around), play.

(Squaring-the-circle is not possible).

Winston
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Re: Could you please help me reverse the volume?

Post by Winston » Tue Nov 17, 2020 6:33 pm

Well, it is cool. If you combine Reverso with Reverse, you can make a Reverse/Rewind CD like effect... CDs jump back instead of smoothly playing backward. With both being an reverse effect, it was double-negatived to a positive, but reversed like a CD.

That is an interesting effect... When you hold the previous button, it sounded like it was skipping, and Reverso combined with Reverse gives a similar effect, except reverses at normal speed.

But, the effect I am looking for needs to reverse the direction while preserving instruments, and/or the other way, at least somewhat. When you reverse a sound fading out, it fades in. When you invert volume, something similar could happen. Combining the two should sound like the instrumental still sound normal/forward, but notes are played reversed.

If anyone finds my message on Reverso, I put it there by accident, I meant to put it here.

Trebor
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Re: Could you please help me reverse the volume?

Post by Trebor » Tue Nov 17, 2020 6:45 pm

Winston wrote:
Tue Nov 17, 2020 5:07 pm
... the effect I am looking for needs to reverse the direction while preserving instruments ...
... like the instrumental still sound normal/forward, but notes are played reversed ...
To play notes in reverse order, but not have them sound backwards, you need MIDI ...
https://youtu.be/ifrS8m7WJKQ?t=215

Audacity only has limited support for MIDI ... https://wiki.audacityteam.org/wiki/Midi

Winston
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Re: Could you please help me reverse the volume?

Post by Winston » Mon Jan 18, 2021 6:29 am

Hello, steve, this

Code: Select all

;version 4
(mult  10 (hp *track* 20000))
didn't work. The first picture is unchanged, the second is with the code, the third is reversed Volume/dB. I want to reverse the sound in dB where the first one looks like the third. Yes, change the entire audio, not just the analysis or that part.
Attachments
FailedCode1.png
FailedCode1.png (138.6 KiB) Viewed 138 times

steve
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Re: Could you please help me reverse the volume?

Post by steve » Mon Jan 18, 2021 11:27 am

Winston wrote:
Mon Jan 18, 2021 6:29 am
this

Code: Select all

;version 4
(mult  10 (hp *track* 20000))
didn't work.
Looking at this:
Image
it clearly did work.
It may not have done what you wanted it to do, but it does what it was designed to do.

Winston wrote:
Mon Jan 18, 2021 6:29 am
I want to reverse the sound in dB where the first one looks like the third.
How did you make that third sound?
9/10 questions are answered in the FREQUENTLY ASKED QUESTIONS (FAQ)

Winston
Posts: 57
Joined: Fri Aug 28, 2020 12:59 pm
Operating System: Windows 10

Re: Could you please help me reverse the volume?

Post by Winston » Mon Jan 18, 2021 11:41 am

It is done with an Image editor, but it is showing what I want to try to do. If the FFT was a line, it would appear flipped upside down. If it was a black-and-white spectrum, the brightness may appear in negative... Am I missing something?

steve
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Re: Could you please help me reverse the volume?

Post by steve » Mon Jan 18, 2021 11:51 am

Winston wrote:
Mon Jan 18, 2021 11:41 am
It is done with an Image editor,
What do you expect that would sound like?

Notice that in the original image, there is no sound at all above about 14,000 Hz. What is the inverse of "none"?
9/10 questions are answered in the FREQUENTLY ASKED QUESTIONS (FAQ)

Winston
Posts: 57
Joined: Fri Aug 28, 2020 12:59 pm
Operating System: Windows 10

Re: Could you please help me reverse the volume?

Post by Winston » Mon Jan 18, 2021 12:16 pm

In other programs, when you invert silence in an entire frequency spectrum (like brightness is volume for each frequency), you hear white noise... which sounds like static.

If the lower half the sound (say 1 - 11025 Hz) is white noise, and the entire thing is inverted, the lower is silent and the upper frequency (11025 - 22050 Hz) is audible (though it was silent before).

That is what I expect it to do...

Is there a volume effect plugin for this, perhaps?

Winston
Posts: 57
Joined: Fri Aug 28, 2020 12:59 pm
Operating System: Windows 10

Re: Could you please help me reverse the volume?

Post by Winston » Mon Jan 18, 2021 12:26 pm

Yeah, it probably would be impossible to be infinity (1/0), but you could reverse the range (0% - 100%) and 0 dB would be the opposite of silence, -∞ (negative-infinity) dB. I'm not sure if the symbol will go through, so if you see a square, it is supposed to be the infinity symbol.

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