• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

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I just few days ago put on simulator the RIAA of kodabmx and is 42 dB with 6N23P as input and 48 dB with 6N2P as input.

to SCD:
is very difficult reach 50-60 dB on RIAA pre-amp. without severe noise problem, unless you insert a step-up transformer like the Lundahl 9206 on the input that is specific for MC cartridge....all the best
 
Class A Balanced Monoblocks

Class A balanced monoblocks, 24WPC
 

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Cleaned up my Kedvesem (Darling in Hungarian): added a choke (monyed om the underside, stuffed another potentiometer in (could have been a 100K, but all I had was a 22K), fixed the pilot light (no big blue LEDs at home ...:(), installed an IEC connector.
Else it is much original shape - DIYtubes/Tom McNallys PCB, 1626 triodes and a 6SL7 as driver. All transformers are Banbury's (now discontinued). Even the choke is Banbury's.
 

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Here's one. This bugger used to be a KT88 push-pull triode connected class A thing I built almost a decade ago for a friend. And now it's come back home. And since I saw no use for it as it was, I decided to give it a remake. Now it's an EL34 UL AB1 PP, first of a pair. Not exactly the prettiest amp I've ever built, but hey! They were originally built in this color as per what the "customer" wanted... The other one (on the left side of the image) is a KT66 PP lab prototype, though when the picture was taken it was running GE 6L6GC's...

The innards are a bit messy, reflecting the much more complicated front end this modified thing has compared to what it was before... It's just a 6U8A pentode/triode connected as a VAS + cathodyne, but stuffing around 20 components where there were originally just a handful was really a, well, a handful...
 

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