On Thursday, April 1, 2021 at 6:47:47 PM UTC+1, Tim+ wrote:
Weirdly I found an old 78rpm record of Harry Gordon stuffed under a hedge
this morning whilst out for a run.

I have a conventional record deck and wondered about playing it once at 45
rpm and recording it and then speeding up the playback.

Would this work?

For some version of 'work'...

If you don't mind the risk to your stylus, you would probably get something out of it.
your 'LP' stylus will be sized for the 'microgroove' of a 33rpm record (hence the phrase,
when the new Long-Playing technology came along). So the stylus will be swamped
in the groove of the old 78. If you just have a cheap ceramic cartridge(*) then I'd
probably give it a go regardless.

The other thing you will have to bear in mind is that the frequency equalisation that
was applied to 78s was not standardised. This later became the standard 'RIAA' equalisation
that your record player electronics will implement, to a greater or lesser degree. There were
a whole load of different curves defined before that - there are charts available.

If you can use an audio editing program (Audacity, Adobe Audition...) then you could apply
a combination of the LP RIAA curve and a 78 curve and get a better result
(highs and lows balanced). It would be an interesting little project.

(*) some of these have a flip-over stylus, one side for LP, one for 78s. If you have a
moving magnet cartridge, you might take the risk. If you have a moving coil cartridge,
then (a) you will know it, and (b) I wouldn't try any of this.

HTH, Jon N