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

I need help to find a schematic for a diy hybrid tube preamp from the eighties

Have received a request from someone who has a DIY tube preamp from the 80s. It has 4 ecc83 in the phono stage and one ecc82 in the line stage per channel. An error has occurred and I have received a request to take a look at the amplifier. There is a separate power supply with a rectifier tube (type unknown) 6x4 or similar, as well as an el34. In the front it says: Stereo Hybrid preamp, so there are probably some transistors in the circuit as well. Does anyone come up with a diy preamp with tubes that people built in the eighties with these tubes, which were hybrid.? The pictures say very little. Haven't received it yet. A typo on the front. Standbuy instead of Standby!
 

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May be a passive RIAA between two gain blocks: two paralleled CC-two paralleled CF-RIAA-two paralleled CC-two paralleled CF
See TubeCad for a similar circuit.

Power supply is a series pass 6CA7/EL34 regulator.