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Gear / Technical Help => Ask The Tapers => Topic started by: gristlejaw on August 01, 2004, 04:05:59 PM

Title: oops Long Play Mode...help?
Post by: gristlejaw on August 01, 2004, 04:05:59 PM
Hey look..my 1st F-up.  Some how the switch on my D8 got jostled enough to switch it from 44.1 to long play mode...so i'm trying to convert it and its playing back all sped up....i've spent about 5 - 10 minutes messing with time stretching with no luck yet..anyone know how to fix this problem?

much thanks,

-gris
Title: Re: oops Long Play Mode...help?
Post by: kindms on August 01, 2004, 04:21:45 PM
If I remember correctly when I did this you have to encode at something like 16/32khz or something simialr.

Did you transfer using 16/48 or 16/44.1 ?
Title: Re: oops Long Play Mode...help?
Post by: hexyjones on August 01, 2004, 04:23:37 PM
I believe the LP mode is a old PCM - 12 bit 32khz sample rate...more like FM radio fidelity...

You will need to upsample to 44.1
Title: Re: oops Long Play Mode...help?
Post by: gristlejaw on August 01, 2004, 06:29:27 PM
Thanks guys. yeah, it was at 32/16 and i got it transferred ok.  it sounds pretty crappy too. I highly recommend never recording in LP mode!!!
-gris


p.s. anyone ever use an ADAT to record from a soundboard before? I see you can get those cheap. I would imagine it would give you a great mixing opportunity.
Title: Re: oops Long Play Mode...help?
Post by: hexyjones on August 01, 2004, 07:23:17 PM
While 32/16 may have worked...the source was likely 32/12

http://www.solorb.com/dat-heads/digests/V6.200/D295#Msg1

{19}    What's the rundown on Long Play mode?

Long-play tapes are recorded at 32kHz, but there are two 32kHz
standards.

The 32 kHz Long Play standard uses a non-linear 12-bit quantization
scheme. That's how they get 92 dB or whatever out of 12 bits - the
buckets at the quiet end of the spectrum are bigger. This means that
you'll theoretically get more distortion at low recording levels than
you would ordinarily. That and the fact that frequency response is
limited to 16 kHz are the trade-offs you make to get twice the time for
your hard-earned DAT dollar. This is because you are storing less data
per second of sound, so you get 240 minutes out of a 120 minute tape.

The other 32kHz standard is a 16-bit one that is (apparently) only used
by the broadcast industry. You get no tape savings as a trade-off of
losing half an octave of music. This is the 32kHz standard supported by
the Panasonic SV-3700 - however, you can only record in 32kHz 16-bit
mode through the AES/EBU digital interface. So unless you have digital
broadcast equipment with an AES/EBU port, you won't have much use for
this mode.