32 bit float import is clipped and distorted

Audacity 3 Help Forum
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[ON Windows 11 but I doubt ia specifict to that platform]

When I import a 32 bit float wav (file → import → audio) from my zoom R4 it is clipped and distorted in places. I saw on this forum that 32bit float is supported. It’s fine when I monitor on the R4 so It would seem a 32 bit float issue - but I thought the entire point was it never clipped?

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I can normalise the export on the R4 but that gives a very low lwvel track.

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Am I missing something in expect the R4 export to work without normalisation?

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It might not be clipped but you can’t see the top of the waveform. :wink: Audacity doesn’t know… It only knows the levels…

But if you play it at “full digital” volume you’ll clip your DAC.

Try running the Amplify or Normalize effects with the defaults. That will bring the peaks down to 0dB (or -1dB with Normalization) and you can see if they are clipped. If the image doesn’t change, it’s clipped.

I can normalise the export on the R4 but that gives a very low lwvel track

That’s OK too. In that case you can Amplify or Normalize to bring it back up.

but I thought the entire point was it never clipped?

There are analog limits so I’m pretty sure you can get clipping while recording. I tried to find that in the Zoom specs once and I couldn’t find anything (just curious, I don’t have a floating-point recorder) . I’d guess it can go up to around +12dB. At some point you’re going to run-out of voltage or overdrive the microphone.

In the digital domain 32-bit floating point can go from something like -700dB to +700dB which can be considered infinite dynamic range because that range doesn’t exist in the electronic or acoustic domain on earth.

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Thanks - I did her some distortion in audacity not noticable on device, but will check.

I also tried the Audacity normalize (-1db) on the Zoom normalized recording but it didn’t increase. I guess there’s a spike somewhere :slight_smile:

I like your suggestion that it might look clipped but might not be clipped and for checking if is clipped :slight_smile: I’ll dig in deeper!

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Ah! Good! It means the Zoom Normalization is doing the right thing. Because, yeah, It “looks” too quiet for a normalized file.

You didn’t try normalizing the “loud” one in Audacity?

To find that spike, do you have View → Show Clipping in Waveform turned-on? Or you can try Analyze → Find Clipping.

And if it’s still not showing-up try Amplify, Allow Clipping, and Amplify for a New Peak Amplitude of +1dB (or anything over 0dB).

If it’s one sample, or very short in duration it might show-up as anomaly in the Spectrogram or Multi-View. Click the 3 little dots to the left of the waveform and select Multi-View.

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Just a note that Recording in 32-bit Float just means the recorder will turn the performance into a correct digital recording no matter how loud it is. That doesn’t mean you can easily play it back later.

Your next job is to convert the carefully backed up performance file to 16-bit linear so you can edit it, listen to it, and produce your final sound product. None of those directly support 32-Float.

That picture of the blue waves filling the timeline is an illustration. Since the show in 32-Float, you can drag the volume down and everything is peachy. If Audacity didn’t support 32-Floating, the blue waves would stop dead at 100% (1.0) and everything from there up would be gone.

Koz

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6

Oh, yes. That’s obvious now you mention it. As even if recording analogue doesn’t clip, playback D/A might.

So in that case export from Zoom is probably best normalised if I want to play on the device I transfer to rather than want 32 bit archive copy. I need to find why is so quiet though.

Thanks.