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View Full Version : Importing audio files for remix - convert or set session to match source audio?


LSW
12-23-2013, 08:41 PM
In PTMP 8, I usually use 24 bit 48 K as my default sessions settings. I have a few songs originally done in Logic 5 on the PC and they are 16 bit, 44.1.

PT will convert these files upon import to my default settings - or, would I be better off just creating a session to match the source files? Is there any benefit or harm with the conversion?

It's OK if there's no benefit, as long as it doesn't mess anything up. It's going to be mostly just a remix, but I may want to add new parts which I would rather do at the higher bit and sampling rates.

Thanks!

musicman691
12-24-2013, 04:17 AM
In PTMP 8, I usually use 24 bit 48 K as my default sessions settings. I have a few songs originally done in Logic 5 on the PC and they are 16 bit, 44.1.

PT will convert these files upon import to my default settings - or, would I be better off just creating a session to match the source files? Is there any benefit or harm with the conversion?

It's OK if there's no benefit, as long as it doesn't mess anything up. It's going to be mostly just a remix, but I may want to add new parts which I would rather do at the higher bit and sampling rates.

Thanks!
Unless you're mixing audio for video there's no real reason to use 48KHz. Stick with 44.1 KHz. As far as your question - work at the imported files rate and depth. 48 KHz isn't going to give you any benefit over 44.1.

LSW
12-24-2013, 01:37 PM
Thank you MusicMan - that was my gut feeling, it's good to have it confirmed.

I've just been going through my projects I've completed over the last 10 years - not a lot of stuff, but it seems that I did more before I got ProTools, which was at V6 when I converted over. The decreased productivity was not the fault of the software, just life things. Logic 5 was really not a very good program. I think that it would only do 44.1/16 bit, or that was the limitation of whatever interface I was using at the time.

But thanks again and Happy Holidays!

Ben Jenssen
12-24-2013, 07:12 PM
Ideally you would create an empty 44.1 session at 24 bits and import the files/tracks. The files would go thru no conversion but any processing or new recordings would benefit from the extra bit depth.

musicman691
12-25-2013, 04:14 AM
Ideally you would create an empty 44.1 session at 24 bits and import the files/tracks. The files would go thru no conversion but any processing or new recordings would benefit from the extra bit depth.
Actually there would still be the upconversion to 24 bit from 16 bit.

JFreak
12-25-2013, 06:45 AM
I only use 24bit/48kHz unless someone pays me extra for 24bit/96kHz.

I've never understood the compromise of 44.1kHz and its upsampled 88.2kHz versions; and had someone asked me, I would have chosen 64kHz as the one and only sampling rate ever available. But that would not have made it possible to enter the bigger-number-is-better game, would it? ;)

musicman691
12-25-2013, 09:11 AM
I only use 24bit/48kHz unless someone pays me extra for 24bit/96kHz.

I've never understood the compromise of 44.1kHz and its upsampled 88.2kHz versions; and had someone asked me, I would have chosen 64kHz as the one and only sampling rate ever available. But that would not have made it possible to enter the bigger-number-is-better game, would it? ;)
The 44.1 KHz is as you know the CD Red Book standard so that's the only reason it really exists. But exactly why that specific number was chosen I have no idea. I know that the electronics in use at the time it was developed may have had something to do with it as well as upper limits of human hearing, but still..........:confused:

JFreak
12-25-2013, 10:46 AM
The 44.1 KHz is as you know the CD Red Book standard so that's the only reason it really exists. But exactly why that specific number was chosen I have no idea. I know that the electronics in use at the time it was developed may have had something to do with it as well as upper limits of human hearing, but still..........:confused:

I know, but it's an end product standard. What's the point in mixing in 44.1/24 because that is not the RB either..?

Craig F
12-25-2013, 12:40 PM
My understanding in part of why 44.1 was chosen was so all on some classical piece that the wife of an exec at Sony love(d) would fit on one disk.

Don't know how correct it is but it's a good story

Bob Olhsson
12-25-2013, 02:17 PM
That story was put out as PR. The real reason 44x16 was chosen is because it was the highest sample rate and bit depth that could be encoded as a video signal in order to facilitate editing with VTRs rather than mainframe computers. The playing length was determined by the length of a Sony UMatic video tape cartridge. The disk is really a miniature Philips video disk that was designed to be pressed in existing vinyl plants.

The pioneers of digital audio found after extensive research that 50 kHz. and 21 bits is the minimum level of quality that can be considered transparent and the optimum would be around 60 kHz. Lower sample rates involve magical infinite filters that don't exist in real world designs.

My experience has been that the damage is already done in the original recording so up-sampling is just adding unnecessary degradation. If I'm starting a recording, I work at 48 or 96 depending on the complexity. If I'm importing audio, I just add 16 bit files to the session but I set the session to 24 bits for recording and 32 float for audio suite signal processing.

RegenerationMix
12-26-2013, 11:29 AM
I always work in 24bit 44.1K for my remixes. I have yet to do a remix at 48K or higher. I dont find any loss of quality since my remix sound files are usually at 44.1K to begin with.


Chris

LSW
09-08-2014, 05:47 PM
Going though my old threads - I sure missed out on some interesting discussion beyond the answer to my question!

I have been a victim of the bigger is better mentality. I once tried to start a session at 96K but it was clear from the start that my hardware wouldn't be able to keep up, so that was that.

The history of all this is fascinating. I remember the first time I heard a CD in a local record store. Everyone was so amazed at the no crackle, pops or tape his, we all missed how dismally "thin" those early CDs sounded.

So why was that that "digital" and "thin" were synonymous? I still don't know, from a technological standpoint at least, what "thin" really means - you just know it when you hear it I guess. ANd I still don't get why, when the two specs that define a sound card/coverter - bit depth and sampling rate - are always at least 24/44.1 yet different devices do sound better. From a computer sound card, to a $100 USB interface to a - whatever - there's a quality difference for sure - yet they all claim the same specs!

Bob Olhsson
09-08-2014, 05:59 PM
Analog line stages sound different and under-powered ones sound thin and strident unless you stay away from the top 10 dB of level.

groundcontrol
09-09-2014, 07:07 AM
Is/was the same on cheap mixer.

Bob Olhsson
09-09-2014, 07:22 AM
Is/was the same on cheap mixer.Exactly!

BigJohnD
09-09-2014, 07:21 PM
The 44.1 KHz is as you know the CD Red Book standard so that's the only reason it really exists. But exactly why that specific number was chosen I have no idea. I know that the electronics in use at the time it was developed may have had something to do with it as well as upper limits of human hearing, but still..........:confused:

I think that the reason the frequency 44.1 kHz was chosen has something to do with the Nyquist sampling theorem. It states (roughly) that in sampling an analog signal, in order to be able to reproduce a frequency of, say 20 kHz, you need to sample at least at the rate of 40 kHz. So, in that context, if you believe that people can hear from 20 hz -20 khz (at least young people can), it makes sense. While heaven knows why the exact rate of 44.1 kHz was chosen, it does provide a reasonable pad above the 40 kHz needed to reproduce frequencies up to 20 kHz. I'm sure that the engineers in the 1970s knew all about the Nyquist theorem. They used to teach math in the last century. We are much more advanced now.

Bob Olhsson
09-09-2014, 07:45 PM
The reason 44.1 was chosen is because it was used by Sony's technology for recording digital audio on video tape. This was adapted for use with an existing Philips video disk that could be pressed in a vinyl plant. To do Nyquist properly with real world filters required a sample rate between 50kHz. and 60kHz.

BigJohnD
09-09-2014, 08:03 PM
The reason 44.1 was chosen is because it was used by Sony's technology for recording digital audio on video tape. This was adapted for use with an existing Philips video disk that could be pressed in a vinyl plant. To do Nyquist properly with real world filters required a sample rate between 50kHz. and 60kHz.

Bob,

Does that mean that CD (44.1) quality cannot reproduce frequencies up to 20 kHz? (if one believes Nyquist)

Bob Olhsson
09-09-2014, 08:12 PM
My understanding is not transparently. Nyquist calls for a minimum sample rate of 40kHz. however that assumes perfect filters which don't exist in the real world. It's an argument about what can be gotten away with subjectively until you get up to 50 or 60 k.

BigJohnD
09-09-2014, 09:20 PM
My understanding is not transparently. Nyquist calls for a minimum sample rate of 40kHz. however that assumes perfect filters which don't exist in the real world. It's an argument about what can be gotten away with subjectively until you get up to 50 or 60 k.

Bob,

That sounds like a good reason to do sessions in at least 48 kHz, as far as recording audio goes.

Bob Olhsson
09-09-2014, 09:28 PM
You've got it. This is why 48k is the standard sample rate for video. It was easier to sync to video than 50. Double and triple sample rates use the same chips so there is no extra cost.