Millenia STT-1

Same as with my other post.  Visiting a frineds studio where they have one of these which doesn't work when you switch to the valve side.  Does anyone have the diagrams.  Does anyone know what valve they take or any other useful spares I can take ?

Guys at Millenia don't like to give their schematics. Their official maintenance guys only have specific part of them once they have identified where the problem is located!
Don't know for tubes... You should open it!
Good luck

https://www.mil-media.com/uploads/original/downloads/Origin%20tube-layout1.pdf

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I had one for many years and in the spirit of 8 year old me I took it apart once to figure it all out.  As a general point - dig into the project schematics on Fred Forssell's website and you will find lots of useful info, he has shared many of the concepts used in this box there (the opto comp, the CAPS eq, the cohen double balanced pre). 

The only area I didn't look closely at was the tube section, I didn't much like how it sounded.  I rarely see tubes fail with silence so I'd suspect PSU issues or switching relays first.

Tubes can fail with silence if their filaments burn out.

Thanks very much for all the tips everyone.  Unfortunately the studio is in a different country & I can't look in the box because I won't get to look at it until I pay the studio a visit next week on Thursday.  Since I return on the  following Monday there will be little chance to get any spares while I am there.  Also there is nobody at the studio until I visit.  I know sounds like an odd scenario ...

I sold mine maybe 10 years ago but there are lots of points in the signal chain where things are switched in and out, insert points etc. I'm betting that if you looked at the signal flow diagrams you could have your friend do some signal flow tests that would help you narrow i down before you travel.

Good luck.

ruairioflaherty said:

I sold mine maybe 10 years ago but there are lots of points in the signal chain where things are switched in and out, insert points etc. I'm betting that if you looked at the signal flow diagrams you could have your friend do some signal flow tests that would help you narrow i down before you travel.

Good luck.

Click to expand...

A great idea in theory but there is nobody at the studio until the day I arrive !