Ideas for my next build project?
« on: February 08, 2019, 03:23:52 AM »
I bought an old Ampro 730 tape machine in a garage sale for $15.
The mechanical transport of the unit is in a very bad condition as well as the magnetic head.
So I want to use the electronic parts to build a tube mic preamp.
The power transformer and the choke seems to be in good condition and it got's enough amps to run a 6X4, 6AQ5, 6AU6 and a 12AX7 tubes.
Any suggestions for a mic pre with a 6X4 rectifire and  6AU6 and 12AX7 preamp stages?
(I don't think to  use the 6AQ5 for a mic pre).
After finding the schematic for this project I'll buy the right input / output transformers and new caps.


Re: Ideas for my next build project?
« Reply #1 on: February 08, 2019, 02:10:42 PM »
Just use the recovery amplifier as a mic pre. A play head is probably like 1K-ish already so it's the right impedance for a mic in. And it should make a lot of gain. If there are higher voltages available for bias use that to make 48V phantom.


Re: Ideas for my next build project?
« Reply #2 on: February 10, 2019, 02:50:41 AM »
Thanks, it sounds like a great idea


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