Spectral DMC 30SS - how to increase Tape Output Pots to Maximum ?

[dgw]

Tape Out from my Spectral does not give out sufficient gain into my Studer A810. It works well but would be better with higher gain. The preamp has "precision dial trimmers" ( under the hood ) on the main system board which allows for adjustment over a 18db range. Two of them = One for each stereo channel. They are "continuously adjustable”. They are marked with "unity gain" at 12 O’clock and "maximum" at 6 O'Clock. But changing from the default unity gain position to the 6 position makes hardly any difference.

So .. does "continuously variable" mean I have to wind the dial around several times to get up to the 18 db gain and how would I know when the maximum output is reached, apart from continuously testing the settings ? And does it mean that when maximum 18db is reached, the dial goes back to Unity Gain and how would I know when this point is reached, apart from keeping on testing the settings ? If this is the case, it could be a long and tedious process to set the dials to maximum 18db gain ?
The Manual does not answer this question.

 

[dan31]

Have you tried contacting Spectral? Mark has been very helpful over the phone. You have a legitimate query so they should be able to help.

 

[dgw]

Unfortunately Spectral USA won't help me because I am not in USA. And my nearest national Spectral Distributor in Germany also won't help because I didn't buy it from them or from one of their resellers. So, I am hoping that somebody here knows the answer ! I think that probably all these kind of continuously variable devices work in the same way and somebody knows about how to use them. Many thanks.

 

[dan31]

Have you set the preamp to it’s maximum output gain? This may help the tape outs. Not sure. You can also check the input gain and be sure that you have the higher input gain selected.

 

[dgw]

Yes, it is set to maximum output gain. And yes it is set to maximum input gain. Extra 18db on Tape Out is available vis the continuously variable pots. So that is my question = how to set those pots.

 

[analogsa]

Could you post pics of the pots in question? If those are the blue ones with a yellow screw head I see, then they are simple single turn pots. Turning them clockwise to the end will ensure maximum gain. The same is true for multiturn pots too, only those require 10 or 20 complete turns to reach the full span.

No potentiometer reverts back to zero, only digital encoders may behave this way.