|
RECord only at 48kHz ... why?
Printed from: Neuros Forums
Topic URL: http://www.neurosaudio.com/community/forum/topic.asp?TOPIC_ID=5528
Printed on: 11/24/2006
Topic:
Topic author: Q-W-Y
Subject: RECord only at 48kHz ... why?
Posted on: 01/25/2005 2:59:16 PM
Message:
Today, i've downloaded HW schemes of the Neuros and i've found interesting thing.
This is Data Sheet of Neuros's ADC/DAC TLV320AIC23:
http://focus.ti.com/lit/ds/symlink/tlv320aic23.pdf
When you look at 29. You will see this table:
http://www.ceskyinterier.cz/temp/NeurosSR.gif
Neuros's block diagram says, that Neuros uses 0;12;15 Mhz for codec_sys_clk.
Now look at the bottom of the table...
"The sampling rates are derived from the 12-MHz master clock. The available oversampling rates do not produce exactly 8-kHz, 44.1-kHz, and
88.2-kHz sampling rates, but 8.021 kHz, 44.117 kHz, and 88.235 kHz, respectively. "
I had synchronization problems with my friend's MiniDisc when we were mixing recordings of his band. Finally i know why. Because Neuros records at 44.117 kHz, not 44.1kHz !! The result was time shift.
I will use only 48kHz sampling rate in future....
Regards,
Q-W-Y
-----Q-W-Y, Czech paranoid android-----
Replies:
Reply author: spacekakes
Replied on: 07/12/2005 10:37:50 AM
Message: quote:
Originally posted by Q-W-Y
"The sampling rates are derived from the 12-MHz master clock. The available oversampling rates do not produce exactly 8-kHz, 44.1-kHz, and
88.2-kHz sampling rates, but 8.021 kHz, 44.117 kHz, and 88.235 kHz, respectively. "
I had synchronization problems with my friend's MiniDisc when we were mixing recordings of his band. Finally i know why. Because Neuros records at 44.117 kHz, not 44.1kHz !! The result was time shift.
I will use only 48kHz sampling rate in future....
Regards,
Q-W-Y
-----Q-W-Y, Czech paranoid android-----
Yeah, that 0.04% difference in sampling rate at 44.1 is really going to be annoying. Why, if you record for ten minutes, the playback will actually last ten minutes plus 0.2 seconds.
Larry
Reply author: bynumite
Replied on: 07/12/2005 2:00:10 PM
Message: Oh man! (light bulb goes off over head). I had the same problem last fall. I was recording the Neuros off the soundboard and some room mics into my old MD to post mix later. It was during mixing I realized they didn't match up exactly. I was able to use an audio editor to compress the length of the Neuros recoridngs, or maybe I lengthened the MD one, I can't recall just now, but that did provide a work-around. I always wondered what happened there.
Larry
Neuros Forums : http://www.neurosaudio.com/community/forum/
© Copyright ©2002-05 Neuros Technology International, LLC all rights reserved.
|