@tschak love it. The best I could do is check for dropout. I'm pretty chuffed that so far I've been able to recover everything from the program tapes I recorded in the early 1980s, though I had to go a circuitous route via #a8cas.
The text in the image reads:
A HELPFUL HINT
What is it that the computer finds so interesting about these tapes? Listen to one of them. I's not music to your ears. Yet you can recognize some of the sounds the computer listens for. The information starts with a steady tone. Then there is a short “blip” followed by more of the steady tone. The tone is at 1000 cycles per second. This pitch is just below the C two octaves above middle C. Alter the tone comes a burst of sound rather reminiscent of a rainstorm.
When you are used to the sound of a good tape, you can quickly check a tape by ear to see if it is a computer tape or not. If you can tell what the tape contains by listening to it, you are a mutant, and will go far in the computer world.