Calibrating Soundcraft Sapphyre 48ch....

[deaf-mute]

Hello,

I recently purchased an old soundcraft Sapphyre 48 track, with patchbay, and
wanted to know if anyone has any idea how to calibrate the VU meters
and the Meterbridge... The same signal differs from track to track.

The board has integrated oscillators but not sure which is the best freq to use, what I should be fiddling with to change the vu meter and where I should root on the patchbay...

I sort of am guessing that the 1khz freq would be the right one, and that that should be patched into each channel's line input and should read 0db,
with the faders at 0---- is this the correct way to proceed?

I'd also like to calibrate the tape send levels if that's possible...

Any help or advice would be very welcome

 

[Tim Brown]

I don't know that board.

But what I always did was send a tone through a channel with the faders set at 0 (and everything flat), so that every meter got the same 0 reading, and that way I knew that my gain structure was "officially" the same through out the entire system.



Tim

 

[deaf-mute]

Thanks for the help tim...

I did some research on this and it's like you said, I need to send a test tone (sine oscillator at 1khz, which is integrated in my mixer). I need to make sure that this signal is at odb which I can do by taking an electronic volt meter and measuring it... I think the reading should read 1.228v.

Once this is checked you can then send that test tone via the patch to each channel via the patch bay's channel line in... Then you can calibrate the vu meters making sure that the output on each channel is at 1.228v for a balanced signal and 0.614v for an unballanced signal. each strip must be unscrewed to get to the little screw where you calibrate the signal.

I think that's as far as I can go at the moment but as soon as I have more info, I'll post it for those who are interested.

Best regards

Andrew

I don't know that board.

But what I always did was send a tone through a channel with the faders set at 0 (and everything flat), so that every meter got the same 0 reading, and that way I knew that my gain structure was "officially" the same through out the entire system.



Tim