Well, 78/33 is 2.36 so 10kHz on the LP will become 23.6kHz when played at 78 rpm, and 15kHz becomes 35.5 kHz.  Are you sure your cartridge is good at those frequencies?  Also, the turnover and rolloff frequencies on your preamp will be working on the wrong frequencies when the LP is played at 78.  This would require special turnover and rolloff playback compensation for the slowed down playback.
What are you transferring it to and how will you slow it down?

Ron Roscoe

-----Original Message-----
From: Association for Recorded Sound Discussion List [mailto:[log in to unmask]] On Behalf Of Richard L. Hess
Sent: Wednesday, August 09, 2017 2:18 PM
To: [log in to unmask]
Subject: Re: [ARSCLIST] Transferring LPs at 78 RPM

In general, I agree with this advice. I certainly do for LPs. I realize the perceived need to speed up the process, but, IMHO, you are better off doing two or three real time transfers in parallel than speeding up a single transfer.

There are some specific instances where I transfer at different-than-recorded speed:

(1) Micro and mini cassettes: I load them into standard cassette shells and then transfer at 1.88 in/s, slowing down the recording by a factor of 2 or 4 for the micro cassette and using a pitch mapping program for mini cassettes.

(2) Logging tapes: I transfer them at the slowest speed I can on whatever reel machine can be fitted with the proper head. I then slow down as needed. These sounded terrible reproduced on machines designed for the purpose back in the day.

(3) Instrumentation tapes: I optimize the on-tape bandwidth to the audio converter bandwidth and then adjust in playback. Faster than real time allows extended low frequency response inherent in FM channels...but if I transfer FM for later demodulation, I will sometimes need to transfer at slower than real time to capture the carrier and its upper excursions.

(4) Squealing reel tapes: Sometimes these can be made to not squeal by running them at 2x or 4x recorded speed.

Just a few thoughts to munch on.

Cheers,

Richard




On 2017-08-09 1:43 PM, Gary A. Galo wrote:
> Lou is absolutely right - real time is the only sensible thing to do, for any and all media.
> 
> Gary
> 
> ____________________________
> 
> Gary Galo
> Audio Engineer Emeritus
> The Crane School of Music
> SUNY at Potsdam, NY 13676
> 
> "Great art presupposes the alert mind of the educated listener."
> Arnold Schoenberg
> 
> "A true artist doesn't want to be admired, he wants to be believed."
> Igor Markevitch
> 
> 
> -----Original Message-----
> From: Association for Recorded Sound Discussion List 
> [mailto:[log in to unmask]] On Behalf Of Lou Judson
> Sent: Wednesday, August 09, 2017 1:40 PM
> To: [log in to unmask]
> Subject: Re: [ARSCLIST] Transferring LPs at 78 RPM
> 
> Why would one do that? You lose the accurate RIAA (or other) curve, and probably damage both the groove and the stylus, plus losing the high frequencies... Don't do it! And with the ratio of 2.34 (...) would you get the pitch just right digitally?
> 
> I get paid by the hour, so I'd do it realtime. I transfer everything I do at realtime...
> 
> <L>
> Lou Judson
> Intuitive Audio
> 415-883-2689
> 
> On Aug 9, 2017, at 10:15 AM, 6295LARGE . <[log in to unmask]> wrote:
> 
>> Hello everyone
>>
>> If I transfer a vinyl LP at 78 RPM then slow it down to proper speed 
>> do I lose anything?
>>
>> Regards,
>> Ben Roth
>>
> 
-- 
Richard L. Hess                   email: [log in to unmask]
Aurora, Ontario, Canada                             647 479 2800
http://www.richardhess.com/tape/contact.htm
Quality tape transfers -- even from hard-to-play tapes.