I need a little help setting up a Studer A800

[Robert Stevens]

The manual is a bit hard to decipher, somewhat inaccurate at times, and for sure out dated.

I want to set the my machine for +4 operation (320 nWb/m). Eventually, probably increase it to +6 but I want to start conservative. I've set the jumpers in the VUs to +4 position, and aligned the inputs on VU meter for a +4dbu 1K sine wave to -7vu with the calibrate button pushed and 0vu with it out. I believe that to be the correct settings for the sync and repro inputs and record card input. Please correct me if I am wrong.

Now I have a 250nwm test tape. I will be using Quantegy 499 to start. Do i set the 1K test tone to 0vu or -3vu or something else (the jumper thing in the vu meter is what is confusing me here). Remembering that I am not going for +6 operation out of the box but rather +4.

Thanks...

[Mike Rivers[_2_]]

On 8/31/2016 5:27 PM, Robert Stevens wrote:

> I want to set the my machine for +4 operation (320 nWb/m).
> Eventually, probably increase it to +6 but I want to start
> conservative. I've set the jumpers in the VUs to +4 position, and
> aligned the inputs on VU meter for a +4dbu 1K sine wave to -7vu with
> the calibrate button pushed and 0vu with it out. I believe that to
> be the correct settings for the sync and repro inputs and record card
> input. Please correct me if I am wrong.

> Now I have a 250nwm test tape.


The +4 jumper sets the meter calibration so that 0 VU = +4 dBu. This is
what you want.

The basic principle of any reference fluxivity calibration, or any
recorder calibration for that matter, is to first set up the reproduce
section, then use that as your "test meter" to set up the recording
section. So the first thing you want to do is play your calibration tape
and set the reproduce level for the proper reading on the VU meter. The
bible for using a calibration tape is MRL's publication "Choosing and
Using MRL Calibration Tapes" which you can download here:

http://mrltapes.com/choo&u.pdf

According to the table in that publication, if you have a 250 nWb/m tape
and want to set the recorder up for 32o nWb/m, set the reproduce level
so that the VU meter reads -1 dB

Then check the repro EQ to be sure it's flat and adjust if necessary.

Now you can start on the record side. Set the bias however you want for
the tape you plan to use, probably somewhere around 2 dB drop over the
peak at 10 kHz, then set up the record EQ, and finally, with +4 dBu
going in, set the record level so the VU meter reading the repro level
reads 0.

And after doing that 23 more times for the rest of the tracks, Bob's
your uncle.




--

For a good time, call http://mikeriversaudio.wordpress.com

[Scott Dorsey]

Robert Stevens > wrote:
>The manual is a bit hard to decipher, somewhat inaccurate at times, and for=
> sure out dated.

Join the Studer mailing list, there are a lot of folks with those machines
out there and most of them are on the Studer list which I believe is hosted
at recordist.com still.

>I want to set the my machine for +4 operation (320 nWb/m). Eventually, pro=
>bably increase it to +6 but I want to start conservative. I've set the jum=
>pers in the VUs to +4 position, and aligned the inputs on VU meter for a +4=
>dbu 1K sine wave to -7vu with the calibrate button pushed and 0vu with it o=
>ut. I believe that to be the correct settings for the sync and repro input=
>s and record card input. Please correct me if I am wrong.

I think you're confusing two things here, the operating level of the inputs
and outputs, and the level to tape.

The first question is what reference tape you're using. If you buy the
320 nW/m reference tape from MRL, then you set the machine up so the meters
read zero when playing back the tape.

The _voltage_ levels of the inputs and outputs when the meters are reading
that way are set by those straps.

>Now I have a 250nwm test tape. I will be using Quantegy 499 to start. Do i=
> set the 1K test tone to 0vu or -3vu or something else (the jumper thing in=
> the vu meter is what is confusing me here). Remembering that I am not goin=
>g for +6 operation out of the box but rather +4.

I would suggest you FIRST do the straight alignment to 250 nW/m since that
is what you have the tape for. Set the azimuth, then set the playback so
that the meters read zero.

If you want to set to a higher level, then you set the playback so that the
meters read _lower_ than zero... which would be -4dB across the board playing
back a 250 nW/m tape. Because the tape is _lower_ than the level you want to
be setting in that case.

Once you have the repro alignment nice and flat and the meters stay rock
solid when the tone ladder is played back (and the azimuth is rock steady too)
then you can do the record alignment.

Once you get it on the mark, touching the alignment up before each session
becomes a ten-minute job.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."