Audacity Forum

Just a thank you Steve, for the last post.
I've been sidetracked and not taken a close look at it yet.

In the picture you provide of PDM, and your quote: "The red line represents the analogue waveform, that is "high" when the density of "ones" is greatest, and "low" when the density of "ones" is least". The high is shown as being at the centre of the ...

Thanks for that, Steve. There are things you mention that I hadn't picked up on from reading the general blurb available. I need to read the PDM stuff more carefully. I don't get why the middle of a group of 1's would be used as a peak, instead of at the end (where the 'real' peak would be). No doub...

I've just been getting an explanation from another forum too! I thought that 1 bit per sample meant the value of the wave would increase 1 step up the 'ladder' per sample of bitrate, which would slow down any transients dramatically. It was pointed out to me it doesn't work that way, but a '1' value...

OK, I've finally twigged why bitstream editing is so difficult, LOL.
You don't have a simple amplitude value to adjust, you have to recalculate the whole wave...

That's just the file layout again. If I assume that the binary bits are added for 1 and subtracted for 0, then it would be impossible to get the up and down spikes that we see in Audacity, unless the bits are summed every n samples. But if that's the case, it's hardly bitstream, is it? ...or is the ...

Steve, I know I'm drifting off topic now, but I've taken a look at the file format, and it seems relatively straightforward, but - this is the important bit - how does the data in the dsf file translate into a wave form? Any clues appreciated, but I do understand if you don't want to wander down tha...

The patch I initially found is here: https://sourceforge.net/p/sox/mailman/message/34464900/ Although it looks like there's more to the thread than just that patch... https://sourceforge.net/p/sox/mailman/sox-devel/thread/1442412990-20764-2-git-send-email-mans%40mansr.com/#msg34464900 I assume the s...

I did play with a format converter to do DSD -> PCM -> DSD , and that process also removed some of the noise from the signal; but it also messed up the timing in the file too - waves weren't where they used to be! That was one of the reasons I thought I'd try to remove the noise natively (relatively...

That's what I meant, LOL. :roll: With DSD128 the sample rate is 5.6 Mhz; I was curious as to what would happen if you attempted to remove all the spurious ultrasonic noise. The waveform looks a lot better (especially if you do the averaging more than once), but I can't recreate the DSF to see if the...