I'm not overthinking anything...and I didn't have to go to graduate school to know that you can do all kinds of numerical crunching with a DAW.
I'm concerned about the mechanical aspects of the original deck and the yet-to-be decided upon surrogate deck, operating at a yet-to-be disclosed speed.
Do we even know at what speed the original deck operated...?
I'm curious...besides the theoretical considerations...how many times has anyone here taken a cassette tape that was recorded on a high speed deck...played it back at a different speed on a different deck...transferred that into a DAW...and then used the DAW's time stretch and pitch correction to make it sound exactly like it did when it was played on the original deck that it was recorded on...?
But that really wasn't even what I was talking about.
I know that if you just focus on the numbers, it's all basic math...but time stretching the audio in the DAW is not the same thing as doubling or halving the original tape speed, and you can only stretch an audio track to a point before it doesn't sound right.
Again...this is non-graduate school, simple stuff...
...if you record 4 notes played at a tempo with each note 1/4 second apart...and then you want that stretched to last for 2 seconds...it won't sound the same, even if the notes stay on pitch.
At any rate...I'm a simple guy, I want to see it to believe it, because too much theory sounds good, and then you find out that the audio doesn't sound quite right after it's been sped up, slowed down, time stretched and pitch-shifted into submission...but we are so far ahead of the reality here that starts with first finding an appropriate playback machine or at least trying to figure out what's wrong with the current machine.
So I'm not really the one overthinking it...let's start with Step 1.