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Digitising 78s without a 78rpm turntable

T

Tumeni Notes

pfm Member
I had been harbouring thoughts for a while of digitising some or all of my Dad's 78s, which had been languishing in a cupboard in the family home since the 1980s or so, and which had languished in a corner of my music room since the early 2000s.

I've been editing audio files with Audacity for years, and noted that the Pitch and Speed adjustment feature included presets for adjusting between the standard TT speeds - 33 to 45, 45 to 78, etc. I had toyed with the idea of getting the Rega Planar 78, but noted that the TT was £400, whereas £80 would get me the RB78 cartridge .... so I looked out the old Rega Planar 3 that I have as a secondary TT, and ....

Purchase Rega RB78 cartridge, remove existing Audio-Technica ATF-5 from the P3 and install RB78. Minor snag - the RB78 has only two tags at the rear, not four, so either the left or right of the arm cables is connected to the cart, with the others tied up out of the way. Single RH channel can be later converted to Mono in Audacity.

Removed current TT felt mat to avoid contamination, and replaced with an old rubber mat that was previously used for record cleaning duties

Clean 78s prior to playback - cleaning fluid is tap water with some washing-up liquid and a few drops of wetting agent, rinse under the tap, then final rinse with purified water. Paint pads from B&Q are ideal for applying the fluids. Leave to dry. Once dry,

Set to 45, connect recorder (Tascam) to Tape Out, and drop stylus. Take WAV file to PC, load into Audacity, make corrections including preset speed adjust, save as FLAC

I'll try and add some pics and screen grabs later.
 
Great project. The British Library use Shure M44s with a range of stylii from ESC with different tip sizes depending on the groove width of the disc - though that's obviously not the cheapest solution and another rabbit hole...
 
I see a transfer service offered online, using EMT 950 TT with varying carts depending on source disc - 10" discs £12 per side, 12" at £14 per side, and Manual restoration (using Cedar) at £28 per hour.

£80 for the cartridge has almost paid for itself.
 
One thing to note is that recording at the wrong speed and then using digital Pitch & Speed adjustment to fix it will result in loss of output at one of the frequency extremes if the source and capture device do not have enough frequency response bandwidth to capture the full frequency spectrum that's produced at the capture speed. For example, say you have a tape deck that only runs at 7.5ips and has a frequency response of 30Hz-16kHz....

If you try to digitise a 15ips tape using that deck, it will play at half speed and all of the frequencies on the recording will drop by an octave. However, because the deck can only playback frequencies as low as 30Hz, any frequencies below this are lost, so when you speed the recording back up in the digital domain to double speed using a Pitch & Speed adjuster, the lowest frequency on the sped up file will now be 60Hz.

If you try to digitise a 3.75ips tape using that same deck, it will play at double speed and all of the frequencies on the recording will increase by an octave. However, because the deck can only playback frequencies as high as 16kHz, any frequencies above this are lost, so when you slow the recording back down in the digital domain to half speed using a Pitch & Speed adjuster, the highest frequency on the slowed down file will now be 8kHz.

Given the limited bandwidth of 78rpm records I suspect this won't be an issue but I'd still recommend capturing at as close to the correct speed as possible. For 78rpm records, capturing at 45rpm will preserve more low frequency spectral information than capturing at 33rpm since you aren't having to speed it up as much post-capture.
 
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