Ripping cassettes at high speed

I have a large number of audio cassette tapes that I need to convert into MP3s. I have been using Audacity for this process as described in the Audacity manual, but it is slow going because each tape needs to be played in real time. I am wondering whether it is worth buying a cassette deck that can play tapes at high speed, and then use Audacity to correct speed and/or pitch once a tape has been ripped. Would that work? Would it downgrade the sound quality? Any tips or advice would be welcome.

Maybe if you had a high-speed duplicator. Just blasting a tape past normal heads at high speed is almost guaranteed to lose the crisp high frequencies—given that the tape had them in the first place. Heads are tuned and balanced for speed. Nowhere is it written you couldn’t balance a set for double speed, but then they might not work so well at X1.

Also jury’s out on what happens to Dolby and DBX if you do that. Both of those are delicate balances between show tones and volume.

Dolby made their name by being the first reliable noise reduction service you couldn’t tell was working. I can imagine throwing all the balances off by changing the speed (and pitch) of the show.

Koz

Yes it would work.
Yes it would downgrade the sound quality (and as koz wrote, Dolby Noise Reduction would not work correctly, so you would need to play back with Dolby Noise Reduction turned off, which would mean more hiss).
Encoding to MP3 also reduces the sound quality.
If you want the best sound quality, record at normal speed and export is a lossless format such as WAV of Flac. If you really need to use MP3, set a high bit rate such as 220 - 260 kbps VBR (preset “Extreme”).