Akarakrit Uamkruea, blogger and audio gear maker who passionate in vacuum tube, audio & music.
Producing electronics projects since high school. Seriously upgrade and modify vintage audio equipment for “Real Sound” concept.
He is a co-founder of Soundaries, all audio solution provider.
Experienced and lively explore the listening rooms & audio shops in Japan as his most favorite to do.

Monday, July 21, 2014

Monday Modify : Continue With NEC Mono-Block Part 3

Just hear the sound from these Siemens F2a mono-block amplifiers.


After finish assembly these amplifiers. I've found the problem with "Hiss" sound 
and try to discover the main cause.

Not from ground-loop or components but I missing "Grid Stopper" 
on WE409A/6AS6 the driver tubes.

Problem's gone when install carbon composition resistors on their grids.

Waiting for spray their cover part to complete the look.






So my cat fell asleep with the sound from this amplifiers. ZZZzzz