Anyone calibrated a TSR-8 ?

[teamdresch]

A friend of mine got one ( almost unused - great condition ), and I had a quick look through the manual .. obviously he's going to have to open up the machine, but how hard is it to get at the calibration points?

[blues-hacker]

I guess the first question I have is Why? what is the machines use history, if known ?

What / how will the machine be used?

the biggest factor in pro studios doing frequent calibration, is setting the machine to various tape types, or working with tapes perhaps started on another machine, ie, setting a balance factor between machines

If this is a home studio use, and user is satisfied with Quant-456, which I believe the TSR-8's were factory cal'd to, unless you have an oscilloscope, and some other tech tools, and an appropriate cal tape, you're not really going to be able to cal it anyways - better off having a local reputable service center check it over, verify it for 456, and take it home and enjoy it.

just my .02

b-h

[Herm]

I agree if it is working well and there is no sign of something amiss I would leave it alone. Clean the heads do demag and start recording.

[regebro]

Basically, feed it 0db line level signals on all channels (and 0db here means 0db in relation to whatever level it wants, that is, +4dB or -10dB, whatever it is), a 1000 hz tone or something similar. The VU meters should all show 0 dB. Press record. Rewind, play back. The VU meters should still show 0db. The signal that comes out should be the same level that the one you sent in.

If this all happens, then it's probably fine. If you want to be picky, you can do the whole thing over on 100Hz and 10kHz. And if you want to be really picky, buy a calibration tape, and make sure that whatever IT plays shows up as 0dB.

When you have done all of this, you have calibrated it. Unless it's strangely calibrated, you don't need to actually tweak anything.

[The Ghost of FM]

Originally posted by teamdresch
A friend of mine got one ( almost unused - great condition ), and I had a quick look through the manual .. obviously he's going to have to open up the machine, but how hard is it to get at the calibration points?

The calibration controls should be accessible by opening the bottom cover.

Lay the machine on its back to gain access to this area of the machine.

Heed the warnings all ready mentioned here and good luck!

Cheers!

[Muckelroy]

I have made a "test tone CD" from generating sine waves on Sound Forge (1K, 10K, 100Hz), and burning it to 2-minute long tracks on an audio CD.

When calibrating the input levels, would it be accurate to play the CD, run it through a channel on my mixer setting it to 0dB on the mixer meter, and then run it to each channel, one at a time, on the tape machine? (given that I set the machine to monitor "source" on the meters, and all)

I guess my question in a nutshell is this: can a mixer meter be used to accurateley set a source tone to 0dB, or do the mixer meters require calibration as well ?

-callie-

[A Reel Person]

that tape decks more than several years old will all need a bit of touch-up calibration.

The good news is, that the dropoff of signal, or discrepancy between record & playback is usually minimal, and even if it indicates calibration would help, it's still useable as-is in most cases.

In some cases that would mean hitting the tape a little extra hot to compensate for minor calibration issues.

Okay?? Okay!!

[Muckelroy]

it was just a yes or no question....

[BRDTS]

.....A friend of mine got one ( almost unused - great condition ), and I had a quick look through the manual .. obviously he's going to have to open up the machine, but how hard is it to get at the calibration points.....?
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As mentioned, all the pots are at the bottom. Before proceeding through the section 3-5 calibration, make sure all dbx is off and make sure you're using a new test tape. Old test tapes are notorious for giving false readings on the voltmeter scales.

[BRDTS]

........have made a "test tone CD" from generating sine waves on Sound Forge (1K, 10K, 100Hz), and burning it to 2-minute long tracks on an audio CD.

When calibrating the input levels, would it be accurate to play the CD, run it through a channel on my mixer setting it to 0dB on the mixer meter, and then run it to each channel, one at a time, on the tape machine? (given that I set the machine to monitor "source" on the meters, and all)

I guess my question in a nutshell is this: can a mixer meter be used to accurateley set a source tone to 0dB, or do the mixer meters require calibration as well ? ..................

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What's the tape machine? Are you still talking about a TSR8? If so, and if your mixer is referencing 0db on its own meters to -10, sure, you can calibrate the tones that way to the tsr8 input pots. Input pots don't typically drift that much, so a -10, input at the tsr will probably already go to zero on the meters.

But, if 0db is referenced to +4 on your mixer, you sure don't wanna be changing the internal tsr8 input pots to get a zero reading that way!

[The Ghost of FM]

Originally Posted by Muckelroy

I have made a "test tone CD" from generating sine waves on Sound Forge (1K, 10K, 100Hz), and burning it to 2-minute long tracks on an audio CD.

When calibrating the input levels, would it be accurate to play the CD, run it through a channel on my mixer setting it to 0dB on the mixer meter, and then run it to each channel, one at a time, on the tape machine? (given that I set the machine to monitor "source" on the meters, and all)

I guess my question in a nutshell is this: can a mixer meter be used to accurateley set a source tone to 0dB, or do the mixer meters require calibration as well ?

-callie-

If you're looking for a yes or a no, the answer is no.

Specific voltages and/or magnetic flux levels on a calibration tape dictate what is or isn't 0Vu on a meter.

Cheers!