MOTUnation.com

Hello,

I have lurked on Unicornation for a long time without posting - because I can almost always find answers from the great posts - what a resource!

I run a recording studio at the University I teach at and we ran into a problem. We have a PreSonus 8 Channel Digital Pre used with a MOTU 2408mkIII - G5 w/ DP 4.6...

Whenever we use the PreSonus we have to sync the clock source to it as we do not have a Big Ben (really want one though)... Anyway DP is set to 44.1K sample rate at 24 bit but the clock source is synced to the PreSonus.

The problem:

The front button on the PreSonus was accidentally set to 48K - so for the last two days recording session all the audio was recorded with DP thinking the audio is 44.1K sample rate even though the clock it was synced to was actually producing 48K.

So now if we playback any of the audio with the clock source back to internal it plays the audio slow - like a record player playing a 45 at 33 speed... As long as DP syncs to the PreSonus set at 48K it plays back correctly. If we try to bounce to disk the resulting audio is played back too slow... Is there any solution to this problem other than mixing down each tune through an analog process?

Thanks in advance for any help!

Brian Gorrell
University of Central Oklahoma

soundhack.com

With soundhack, the sound file headers can be changed from 44 to 48......one at a time though.

Something like Audioease's Barbabatch can convert many files at a time, but it costs quite a bit.

Or you could maybe time compress (Scale Time) the soundbites to 91.875%.

I thought when you time compress the PITCH stays the same and only the tempo changes - I would need the pitch to come up as well as tempo???

Thanks,
Brian

What Tim said -

Soundhack will do it easily.

Cant you just set DP to record at 48 in the future? Or do you need 44.1 specifically?

Hi Brian,

Yeah, it stinks when this happens. Here is how to think of the problem.
The files are tagged as 44.1k in the file headers. However, you actually recorded audio at 48k. So if your clock is internal, DP thinks they are 44.1k files, and plays them at that rate, hence they sound slow.

You need to first change the file headers. I would try sound hack like Tim suggested. Before OSX, you could do this with resedit. It's been awhile since I last did this.

1. Use Sound hack to change the file headers to 48k for all the sound files. This might be tedious.

2. Now the system will see these audio file as 48k. If you set the 2408 to the internal clock, it will play back at 48k and sound normal.

3. If your ok with 48, keep the project like that. It is a valid 48k project now.

or

You could then convert the sample rate for all the files from 48k to 44.1k in the soundbites window. This does not affect the pitch. Then all your audio would be in 44.1k.

Suggestion: If you can, set the PreSonus to clock externally at 44.1k. It will either lock to the digital connection (out from 2408 to PreSonus if possible) or take word clock out of the 2408 to the word clock in on the PreSonus, if you have this option. Leave the 2408 on internal. Note: it looks like you do have this option if I have the right image here. http://www.presonus.com/images/diagram_ ... max_lt.gif


This way you can avoid the mistake of the Presonus accidentally being set to 48k and running into this again. If the 2408 is on internal 44.1k, and the PreSonus is on External clock it should stay always stay locked to 44.1. and if it doesn't you probably hear some nastic digital static to alert you to the problem quickly.

Good Luck!

You actually don't want to leave the 2408 on internal if the Presonus has a better clock, which I'm sure it does. Just about anything has a better clock than the 2408!! You can test this easily by switching back and forth from internal to word clock and judging which sounds better to you. It won't change the processing going on inside DP, but it will affect your mix decisions since they will sound different.

I personally am using a Yamaha 03d with a couple 2408's, and the clock quality difference between the two is staggering.

wow I never knew you could do that! I have always recorded out analog to another DAW (or even a DAT machine) & then recorded back in at the proper settings. Very cool tip.

Man I hated seeing that someone had the 02R set to 48K while I was recording at 44.1 - geez

briangorrell wrote:I thought when you time compress the PITCH stays the same and only the tempo changes - I would need the pitch to come up as well as tempo???

Thanks,
Brian

Oh yeah......that's me typing before thought process completed.....that, or synapses entered my vast dead brain cell dump site (even though it's fenced in, with "No Trespassing" signs).....

Which reminds me...
I don't know if DP still does this, but when a 44.1k project is referencing a 48k clock the sequence may be going faster, eg. a seq at 44.1 bpm will be traveling at 48 bpm. So when changing the sequence to 48, the tempo may need to be up'd by 108.*********% .

I originally posted this thread back in 2006. I am now opening the project to mix the files and have this same old problem. Except, I am working from another system and can not "trick" DP into thinking it is looking at 44.1K.

I downloaded Sound Hack as was suggested. I went into every single audio file and changed the header from 44100 to 48000. This was loads of fun, considering there was about 300 audio files!!

Anyway, I was all excited and I reloaded the DP project (I'm on 5.13) and DP still looks at all the audio files as though they are 44100, even though I manually changed the file headers on every single audio file!!

At this point, I am wanting to strangle my laptop, but I thought I might beg for help first!!

Any thoughts would be greatly appreciated!

You don't need soundhack to do this. Since DP 5.12 you can do it directly in DP.

-Change your session to 48k.

-Go to the soundbites window. Select 'change sample rate or format' from the mini-menu.

-48000 should be entered in the sample rate to convert to

- Click the option to change the recognised sample rate without processing the audio.


It's done. The project will now play back at the right speed (at 48k). If you want to go back to 44.1k you'll need to re-sample to 44.1k.

Mr_Clifford wrote:You don't need soundhack to do this. Since DP 5.12 you can do it directly in DP.

-Change your session to 48k.

-Go to the soundbites window. Select 'change sample rate or format' from the mini-menu.

-48000 should be entered in the sample rate to convert to

- Click the option to change the recognized sample rate without processing the audio.


It's done. The project will now play back at the right speed (at 48k). If you want to go back to 44.1k you'll need to re-sample to 44.1k.

Bingo! Thanks for the help - would have likely never notice that new option to "change the recognized sample rate w/o processing the audio"!

Unicornation is the best!!

Mr_Clifford wrote:You don't need soundhack to do this. Since DP 5.12 you can do it directly in DP.

-Change your session to 48k.

-Go to the soundbites window. Select 'change sample rate or format' from the mini-menu.

-48000 should be entered in the sample rate to convert to

- Click the option to change the recognised sample rate without processing the audio.


It's done. The project will now play back at the right speed (at 48k). If you want to go back to 44.1k you'll need to re-sample to 44.1k.

While reading this thread, I kept thinking --"man- I thought this was fixed a while ago-- don't tell me we've regressed!!"

Lo, and behold-- it works!! And it still works!!

Mr. Clifford, my friend Gandalf would be as proud of you as I am.