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TonyDuell · 3rd Dec 2017, 7:32 pm

I will admit now that I have not seen this type of machine, so flame me if you like.

I think the tacho head signal would tell you something. If it's rock-steady in frequency then the speed is not varying, and the flutter is either due to something mechanical further on (very unlikely) or the tape is not recorded properly.

Since you think the lower speeds are steady, could you record a constant signal of around 500Hz on tape running at 3.75ips? Then play it back at 7.5ips. You could tell if that was fluttering I think. It would of course play back an octave higher (at around 1kHz) but that is no problem.

3rd Dec 2017, 7:32 pm	#9
TonyDuell Dekatron Join Date: Jun 2015 Location: Biggin Hill, London, UK. Posts: 5,208	Re: Revox A700 flutter only at 7.5ips? I will admit now that I have not seen this type of machine, so flame me if you like. I think the tacho head signal would tell you something. If it's rock-steady in frequency then the speed is not varying, and the flutter is either due to something mechanical further on (very unlikely) or the tape is not recorded properly. Since you think the lower speeds are steady, could you record a constant signal of around 500Hz on tape running at 3.75ips? Then play it back at 7.5ips. You could tell if that was fluttering I think. It would of course play back an octave higher (at around 1kHz) but that is no problem.