OT: USB turntable and Audacity

Dave M DaveM at Mich.Com
Fri Jul 14 18:56:15 UTC 2006


At 02:18 PM 7/14/2006 , Anne wrote:
>Has anyone done any speed-adjustment work in audacity?  Is it possible?

You can do this with any editing software that will allow you to re-sample 
and equalize the recording.

Run the output of the turntable into your Mic input. Dont use an amplifier 
or equalizer because the equalization curves will be wrong. You then record 
your 78 (I typically use 45rpm) to a an uncompressed file. Then resample 
the file (by a ratio of 78/45) to speed up the playback.

After the file is re-sampled, you must then use the software to equalize 
and filter the file. If you are going to convert it to an ogg or mp3, only 
do so after doing all of the above.

There are lots of equalization curves that where used on 78's so you can 
look up the curves or just do it by ear. Also, not all 78's are actually 
recorded at 78. The speed ranged pretty widely. As high as 80 and as low as 
75. So if it sounds a bit off key, you can play with the speed ratio in 
order to correct the speed.

Keep in mind that the stylus used on 78's is much larger than the one 
typically used on 33's and 45's. Depending on the turntable it takes a 
little hunting to find the correct stylus for your cartridge. Last time I 
checked, they where still avalable for the Sure cartridge. It is best to 
use the correct stylus, using the smaller stylus can damage the record or 
the stylus and usually results in a rather distorted recording.

You can find more info here:

http://www.rfwilmut.clara.net/repro78/repro.html

It is a good idea to archive the uncompressed file (or use FLAC to save it 
using loss-less compression). Archive.Org is a repository for the 
digitization of these old recordings. I am sure they would love to have a 
copy of whatever you digitize. You can upload the files to their website. 
You may even be able to find digitized copies of your recordings are 
already there.

Feel free to contact me off list if you have questions.


-------------------------------
Dave M
Davem (at) Mich (dot) Com
Ann Arbor, Mich. USA

Endangered electronic species: http://www.eff.org/endangered/list.php
"The 'Analog Holes' they want to stop up are our eyes, ears and mouths."




More information about the users mailing list