jpbeale wrote:
> I think the Sony MZ-RH1 has already been carefully studied by many
> more qualified. But just to add to the available data, I measured mine
> to have an input noise level of -122.8 dBu (A-weighting) using the mic
> input with "High" sensitivity and +30 recording level. Graphs from
> RMAA are shown on the pages below. The mic input shows a bit more
> rolloff at low frequencies than line input.
>
> http://beale.best.vwh.net/measure/audio/MZ-RH1_MIC.htm
> http://beale.best.vwh.net/measure/audio/Sony_MZ-RH1_line-in.htm
>
> Since my audio attenuator has an output impedance of 1 kohm it may be
> slightly more noisy than a 150 ohm source (about -127 vs -129 dBu I
> think).
Thank you very much sharing your professional measurements.
I agree that the relatively high output impedance of 1 kohm results in
a higher noise level. Though, I guess that a 150 ohm source might
improve the noise figure by more than 2 dB. You could measure the
noise at 150 ohm simply by replacing your attenuator by a plain
resistor of that size. The 1 kHz reference signal with the attenuator
are only required to calibrate the setup. Unfortunately, this change
of the output impedance might also slightly change the input
sensitivity of the recorder (depending on its input impedance).
Regards,
Raimund
|