Need some tube help!

[mixich]

HI,I got few Q's...
I have a mic preamp Presonus that has ordinary 12AX7 tube (which is an equivalent for the europian name for a tube "ECC 83" ).
Now I want to try an experiment and change the factory tube with one Telefunken tube from my 1955 Blaupunkt radio.Old but good preserved.Anyway none of the tubes I've got is ECC 83.
The tube names are:
ECC 85
ECH 81
EABC 80
EF 89
EL 84
1.Does somebody knows what are these tubes for and could I use some of
them for my experiment with the preamp?
2. Could I use that preamp as a DI box with some other tubes used in guitar amps?
3. Could I use some of these tubes with a tube Mic ?

Thanks

[Ty_Bower]

You need to go here: TDSL Tube search

Type in the number of each of your tubes, and you will find out what it does.

You may find the links which lead to "The National Valve Museum" particularly interesting.

[pauldune]

The ecc85 is usable as a replacement for the ecc83; however it has less gain; 55x instead of 100x. The connections are the same; but the curves are different. So if it will work in your mic? Who knows... probably the resistors need to be adjusted.

[llwhtt]

The ECC85 (6AQ8) only has a 6 volt heater, so if the ECC83 is running on 6 volts it will probably work. At least it won't hurt anything. That was a very popular tube with Luxman years ago.

Craig

[mixich]

Thanks guys...