So I've got this edirol fa-101, mac mini w/ core audio, and cubase se recording into AIFF files.
I guess I thought this was 24-bit audio since the edirol says 24-bit on it, and so does the cubase meta information.
Upon replay, running a VST plugin that counts data bits in an audio stream ... it really looks like 32-bit data. This makes sense really, to ensure even wordcounts when processing in a computer -- but whats really going on here?
Is all my audio really 32-bit? If I archive this to flac/24 is the compression I'm seeing only due to the fact the extra 8 bits have been truncated?
its possible the app your using works in 32bit float files.
I'm sure it does, and the data coming from my AD apparently does too (because theres actual data after the 24-bit mark).
Anyone else have experience here? I guess theres no chance of my flac'ing these without losing that extra data huh?
Refreshing this thread with an update (since I got no real answers last time).
I guess I need a real hardware guru to answer this one. I'm not debating the utility of high-resolution audio recording here, this is strictly a detached technical discussion.
I record audio with my "24-bit" (at least thats whats painted on the side) Edirol FA-101 over firewire 400 to a mac running cubase se.
So:
Edirol FA-101 A/D (24-bit?) --> 1394 400 (32-bit) --> Mac OS X (32-bit) --> Cubase SE (32-bit)
Everything supports 32-bit float except the A/D (supposedly).
Now I found this neato plugin (that escapes me at the moment). It simply decodes the digital values of each audio frame, and lights up 32 lights on a colored strip when they change inter-frame. The resulting effect is a visual representation of the bit-depth of the audio being forced through it.
When I play my FA-101 recordings (32bit float files remember) I get 30 to 31 bits of detail on average. This is in contrast to a "24-bit flac" recording which indeed shows 24-bits, and a CD audio file which properly displays 16-bits of detail.
This seems to indicate my files contain almost (if not completely) 32-bits of detail. so ... is my Edirol likely decoding at 32-bit and edirol is just advertising 24-bit for product differentiation purposes? Maybe I'm just seeing noise on the 1394 bus?
comments/questions?
I can't answer this directly; but I seem to recall that a similar discussion came up regarding how Cool Edit Pro/Adobe Audition deals with files while editing, i.e., the program's "native" format is 32-bit float or some such. That's the best I can recollect.
My question is really hardware specific to the Edirol FA-101, but I wondered if anyone had done similar research on other USB/1394 devices.
I'll try asking yamaha but something tells me:
A) I cant talk to anyone who has a clue.
B) People who have a clue's boss doesnt want me to know I have 32-bit hardware.
anyone here work for yamaha? =)
Quote from: mfisch on December 05, 2005, 03:10:44 PMcomments/questions?
I think Cubase and the plug-in are simply operating in the 32-bit realm. I suspect Cubase is like CEP/AA in that it does not have a native 24-bit file format. Rather, it opens 24-bit files in a 32-bit float workspace. If one saves the file with default settings, it saves as 32-bit float, even if it includes only 24-bits of audio. In such a case, there are, in fact, 8 extra bits of information in this case - but it just so happens all the information = padded zeroes, i.e. no meaningful content. CEP/AA will only output the actual 24-bits of audio content if one specifies the proper Save As settings before saving the file. I think the plug-in cannot distinguish between the 24-bits of actual audio content and the 8 extra bits of filler, so it reads the file as 32-bit.
Then why don't your 24-bit FLAC-sourced files also read as 32-bit? I'm betting because you simply opened these files in Cubase, but did not then save them in the 32-bit float workspace as you do your FA-101 sourced files.
Wanna test this? Open the 24-bit FLAC-sourced files in Cubase and use the same Save As options with those files as you do for your files recorded from the FA-101. 32-bit files. I bet the FLAC-sourced files then, too, appear as 32-bit files to the plug-in (even though they're 24-bits of audio + 8-bits of filler).
Quote from: Brian Skalinder on December 05, 2005, 09:59:01 PM
Quote from: mfisch on December 05, 2005, 03:10:44 PMcomments/questions?
I think Cubase and the plug-in are simply operating in the 32-bit realm. I suspect Cubase is like CEP/AA in that it does not have a native 24-bit file format. Rather, it opens 24-bit files in a 32-bit float workspace. If one saves the file with default settings, it saves as 32-bit float, even if it includes only 24-bits of audio. In such a case, there are, in fact, 8 extra bits of information in this case - but it just so happens all the information = padded zeroes, i.e. no meaningful content. CEP/AA will only output the actual 24-bits of audio content if one specifies the proper Save As settings before saving the file. I think the plug-in cannot distinguish between the 24-bits of actual audio content and the 8 extra bits of filler, so it reads the file as 32-bit.
Then why don't your 24-bit FLAC-sourced files also read as 32-bit? I'm betting because you simply opened these files in Cubase, but did not then save them in the 32-bit float workspace as you do your FA-101 sourced files.
Wanna test this? Open the 24-bit FLAC-sourced files in Cubase and use the same Save As options with those files as you do for your files recorded from the FA-101. 32-bit files. I bet the FLAC-sourced files then, too, appear as 32-bit files to the plug-in (even though they're 24-bits of audio + 8-bits of filler).
I couldnt really figure how to read the results of my test .... Maybe you can give it a go and tell me what you think its doing?
The plugin is available at http://www.tobybear.de/p_utilbag.html (http://www.tobybear.de/p_utilbag.html). Weird that Toby claims there is no mac port, ... Im using it. *shrug* as to where it came from =)