altruistica
Member
I'm calibrating two TASCAM MSR16 machines.
I've already ascertained that these two machines have different 'inception dates' (yeh, been watching too many 'Bladerunner re-runs) as observed in their different audio cards. For those that don't know the machine, one quirk is that there is no control pot for adjusting the input signal on the machines (which may be the problem). The first stage of calibration is checking that a 0.316V (-10dBv) input produces a 0.316V output on each channel. (The manual doesn't mention what you have to do if this is not the case? Anyone know?).
Next is the usual order of affairs, playback MRL, check repro level, meter zeroing, then repro eq, then biaising, then rec levels at both speeds. Finally you should be able to rec levels across the frequency range and play them back within +/- 3dB. All well and good and I've achieved this on both machines........here's the problem though (well two, but I'll ask that one later).
The first is that when I record a 1Khz tone on machine A @ 0VU (or should I say 0dB) (ie. 0.316V), and play it back on machine A, it reproduces at the same level. If I now take this tape and play it back on machine B, it reproduces at -3dB, even though the MRL tape (250nWb/m IEC compensated) I've used on both machines has been set to playback at 0dB on both machines. If I now record a similar tone on machine B at 0dB, it plays back at 0dB on machine B, but when taken to machine A plays back at -3dB. The only thing I can figure out is that machine B (which I suspect is an older machine with audio cards that have the HI/LOW rec levels the other way round...see my other post for that) might have a different internal reference level than machine A. As I said, you don't actually set the input level with a trimmer........it's already predetermined.
I haven't got a manual for machine B so it might be that there was a different calibration level used....anyone know?
I think there will be a workaround for this situation, but I might have to have a think about it.
BTW, the reason why I want two working machines is because if I start taking work from outside, the last thing I want is a machine that has a problem with no way to carry on working. This way I can fix one machine while carrying on working with the other machine.
Could it be that Tascam had a different MRL tape in mind (one referenced to 180nWb/m) for the older machine. If I've understood what I've read, then using a 250nWb MRL on a machine that was expecting a 180nWb MRL, would mean me setting the dB meters on machine B to +3dB. This would then make swopping the tapes between machines possible?
Would I need to calibrate machine B again from scratch (ie would the biasing and rec levels be dependent on the initial repro level /meter adjustment?
Thanks for any help offered.
Al
I've already ascertained that these two machines have different 'inception dates' (yeh, been watching too many 'Bladerunner re-runs) as observed in their different audio cards. For those that don't know the machine, one quirk is that there is no control pot for adjusting the input signal on the machines (which may be the problem). The first stage of calibration is checking that a 0.316V (-10dBv) input produces a 0.316V output on each channel. (The manual doesn't mention what you have to do if this is not the case? Anyone know?).
Next is the usual order of affairs, playback MRL, check repro level, meter zeroing, then repro eq, then biaising, then rec levels at both speeds. Finally you should be able to rec levels across the frequency range and play them back within +/- 3dB. All well and good and I've achieved this on both machines........here's the problem though (well two, but I'll ask that one later).
The first is that when I record a 1Khz tone on machine A @ 0VU (or should I say 0dB) (ie. 0.316V), and play it back on machine A, it reproduces at the same level. If I now take this tape and play it back on machine B, it reproduces at -3dB, even though the MRL tape (250nWb/m IEC compensated) I've used on both machines has been set to playback at 0dB on both machines. If I now record a similar tone on machine B at 0dB, it plays back at 0dB on machine B, but when taken to machine A plays back at -3dB. The only thing I can figure out is that machine B (which I suspect is an older machine with audio cards that have the HI/LOW rec levels the other way round...see my other post for that) might have a different internal reference level than machine A. As I said, you don't actually set the input level with a trimmer........it's already predetermined.
I haven't got a manual for machine B so it might be that there was a different calibration level used....anyone know?
I think there will be a workaround for this situation, but I might have to have a think about it.
BTW, the reason why I want two working machines is because if I start taking work from outside, the last thing I want is a machine that has a problem with no way to carry on working. This way I can fix one machine while carrying on working with the other machine.
Could it be that Tascam had a different MRL tape in mind (one referenced to 180nWb/m) for the older machine. If I've understood what I've read, then using a 250nWb MRL on a machine that was expecting a 180nWb MRL, would mean me setting the dB meters on machine B to +3dB. This would then make swopping the tapes between machines possible?
Would I need to calibrate machine B again from scratch (ie would the biasing and rec levels be dependent on the initial repro level /meter adjustment?
Thanks for any help offered.
Al