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Adding to Richard's helpful comments, there is a vast difference between 
playing grooved disc recordings at much faster than normal speeds (with the 
issues already noted by Gary and others) and playing magnetic tapes at 
faster than recorded speeds. Most importantly with tapes, there is not the 
mechanical issue of a stylus/cartridge having to track at much increased 
velocities: just a static tape head responding to magnetic oscillations. 
Both recording and playback of magnetic media can often be performed at much 
higher than standard (real time) speeds as was done for decades 
commercially. For example I believe commercial pre recorded cassette tapes 
were recorded by the big companies at up to100 times real time on custom 
open reel machines using large "pancakes" of cassette sized tape, cut and 
then loaded into cassette housings. The essential design changes were to 
tape heads, and to amplifiers optimised and EQed for the much higher 
frequencies.

Tim Gillett

Perth,
Western Australia

----- Original Message ----- 
From: "Richard L. Hess" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, August 10, 2017 2:17 AM
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. 


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