[ptr]

Hey there, I'm looking at building an octal monogram cornet, I've just got a couple of questions.

My impression is that it shouldn't be too hard, simply combining the changes in both the octal and the monogram units.  Would this be correct, or are there other changes that need to happen?

Would it be possible to make this unit stereo capable?  I don't need the linestage and I would like to have a unit that is capable of playing almost anything.  I'm making the assumption that the monogram setup is capable of playback equal to that from a standard cornet from vinyl (not 78's), correct me if I'm wrong.  (Or if I'm not making any sense.)

I don't mind doing some fairly esoteric mods, I used to have a job building and modifying prototype electronics, nothing can be as bad as trying to re-route tracks on surface mount gear...

Cheers

Peter.

[hagtech]

The MONOGRAM is only one channel.  That is all we need for a variable EQ system, and I use that to our advantage to free up some tube sections - which are then used for the line stage portion.

So you can't easily make a stereo version.  Not enough tubes to do it.  And no way to reasonably put in a volume control on a Cornet.  

You could probably do an octal MONOGRAM, using 6SL7 tubes.  But you'd have to recalculate EVERYTHING.  All resistors and capacitors would change.  

jh

[hagtech]

Aha, I just realized you didn't need the linestage (volume).

In that case, you could probably adapt the variable EQ sections into an octal.  Again, probably have to recalculate bias, supply drops, and EQ values.  Add the mono switch as in the CORNET2.  Then you could do both mono and stereo records.

Lotta work doing the math.  Good luck!

jh

[ptr]

Cheers, I'd probably need too much help on the maths for that to be practical, I only ever did elementary maths in school and I'm yet to go and rectify that.  I'm far better at building than designing.

I may end up doing things slightly differently.

Cheers

Peter.