View Single Post
Old 3rd Dec 2017, 3:00 pm   #7
TIMTAPE
Octode
 
Join Date: Jul 2006
Location: Perth, Western Australia
Posts: 1,965
Default Re: Revox A700 flutter only at 7.5ips?

Shawthing, are you quite sure your test procedure - of listening to various classical music tapes - is sound? If you are using different tapes for testing the different speeds this could be a source of error. One tape might have more friction, or stiction, than another for example. Or there might be more recorded W & F on one tape than another.

Also, different types of music vary in how much they expose W and F in a tape machine. For example, long, drawn out piano chords are great for revealing Wow. Whereas a musical instrument with much vibrato/tremolo, or short notes in rapid succession, can disguise speed irregularities.

Best to test in a way that the only factor you are changing at a time is the tape speed. I agree with Michael that a scope view of the speed sensor inductor's output would test the capstan motor's speed stability.

Last edited by TIMTAPE; 3rd Dec 2017 at 3:10 pm.
TIMTAPE is offline