(First, I don't think this isn't really a Mac specific thing, though it may sound so at the beginning, and the app mentioned is a Mac editor.)

Comments welcomed:

Wave Editor from Audiofile Engineering is an editor for Mac with some software features provided by iZotope-the sample rate converter, for one.

Wave Editor has preference pane for **Output**:

Either
1. Apple AU Converter [sic]
or
2. Izotope Resampler [sic]

(Again, this is an *Output* preference pane ***within the application***.)

When playing files in the application, there is a marked difference in sound depending on which choice is made. If the choice is made during playback, there is a short disruption, and the playback continues with the new choice.

This difference is easily heard by the others, but there is not necessarily agreement on which is better-though I consistently much prefer the iZotope "resampler". Subjectively, for me, everything about the sound changes: the source has more body and cohesion, the stereo image is more defined, everything has increased clarity, the sound is "bigger," etc. It's just a much more refined sound.

My question goes to what is going on here.

There isn't any sample rate conversion going on, or is there?-when simply playing a file at its own SR? What about routine "under the hood" oversampling for playback?

Note: for purposes of demonstration, I've limited "audition" to just the computer analogue outputs.

1. I've written to Audiofile, and the specific person addressing the issue didn't have any idea of why that might be happening, and evidently there hasn't exactly been a mountain of reports of this effect. (Also said no resampling should be taking place-but-again-these choices are made in the "Output" chain. So that doesn't make sense to me.)

And: why would there even be an output choice if it didn't make some sort of difference?

2. I've written to iZotope, and the specific person answering the query suggested that perhaps something was going on "under the hood" with the application, and that couldn't really be addressed by iZotope.

I think this is more a question about what happens to audio as it makes its way through a computer application or OS.

I've mentioned this very briefly some time ago in the Mac forum in a thread about a related topic, but there weren't any "takers" there.

So:

It sounds great! Could someone tell my why?

Thanks.

I imagine that if you are playing back an audio file that's at anything other than the output format your audio interface is running at, Wave Editor will be resampling for playback using one of the two libraries.

The gap when changing is probably just a cost of switching libraries and restarting the audio engine.

Whether the resampling engine is active all the time or not I don't know, you'd have to get the devs to tell you what's going on here. IN any case, you prefer iZotopes algorithms, so leave it at that. It's probably only a playback thing (though of course the resampling libraries will be used if you neeed to destructively resample your file as well.)

Do you get a marked difference in playback quality when using different rates - specifically, the same rate/bitdepth as your audio interface?

The obvious solution is to record or re-capture the digital output from each of the two options, and then do a null test to see which is the same as the source and which is modified.

hugh

--------------------
Technical Editor, Sound On Sound

Quote Hugh Robjohns:

---

The obvious solution is to record or re-capture the digital output from each of the two options, and then do a null test to see which is the same as the source and which is modified.

hugh

---

Yes, that's obvious.

But before you mentioned it, it was not!

Thanks for that.

desmond-
Thanks for mentioning/clarifying some of the issues. It makes it easier to ask more useful questions.

I expect to first try to ascertain whether differences can be affirmed by following Hugh's suggestion.

Then I will find my way a bit closer to the developers, which shouldn't be difficult in the case of these two firms.

Edit: So far, limited anecdotal comparisons indicate that the effects are independent of interface. I've not yet made comparisons at higher sample rates-strange that I haven't.

Just noticed a discussion elsewhere that claimed that the Izotope resampler was included to get over problems with the Apple resampler.

Why a professional audio interface and professionally oriented program needs a resampler on the output is beyond me but it seems to be a Mac thing.

James.

--------------------
JRP Music - Audio Mastering and Restoration.
http://www.jrpmusic.net

James, thanks for your remarks.

Your presumptions about Mac's, interfaces, and the application under discussion are in error, but I thank you for the contribution and report.