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    Building, troubleshooting and testing of these amplifiers should only be
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    the safety precautions around high voltages.

Layout / Schematic for Tube Mic Preamp with Transformer

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Hi,
Does anybody know of any good layouts/schematics for a simple 1 channel DIY tube mic pre with transformers? I do not need phantom power.

In the circuit I want to avoid any IC chips.

For components my budget target is £100 - £200.

Is this schematic any good?
Build a tube Mic Pre: Build Your Own Two Channel Vacuum Tube Mic Preamp! | Tape Op Magazine | Longform candid interviews with music producers and audio engineers covering mixing, mastering, recording and music production.

I can’t really seem to find anything online. Ideally I want a vintage schematic, but most of all importance is that it is relatively easy to build.
 
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If you want transformers the RCA MI-11241 from the BC-2B is a classic. The feedback
and low current draw make it easy on the transformer so you wont need anything as expensive as an LS27 shown in the schematic at this link. RCA BC-2B Recording Studio Console c. 1952 – Preservation Sound The schematic at the link is correct other than the cathode voltages and transformer numbers. 15K:600 is about right for the output transformer. The input transformer should be about 1:10 turns ratio to get the specified 40 dB of gain
 
Here's a vintage mike preamp to consider. You could build only one channel if needed and omit the phantom power. The expensive UTC transformers can be substituted as well as the tube choices.
 

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