Nattawut 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 and Sentimental Studio, all audio solution provider.
Experienced and lively explore the listening rooms & audio shops in Japan as his most favorite to do.

Friday, April 7, 2017

JBL Graphic Controller Preamplifier & Solid State Energizer Modification

Since 60's, JBL made several audio equipment.

Power amplifier : SE400S, SE408S, SE460, SE400, SE400E, SE401 and SE402

Integrated amplifier : SA600 and SA660

FM Tuner : ST860

And only preamplifier : SG520

All above have great sound and really match with vintage JBL speakers like they've claimed.

But now some components have expired and should be replaced.

Let bring them back to "better" life with high quality components.


SG520 Graphic Controller Preamplifier.


This SG520 just repaired before with standard Japanese components.





So I just replace standard capacitors with Western Electric paper in oil and RIFA electrolyte.






Better look & better sound with long life and high quality components.


Next was SE401 amplifier with Germanium power transistor & interstage transformer !

Top amplifier in picture is SE408S and bottom is SE401.


Indicated for JBL D50S8R (S508) Olympus.


This JBL amplifier was repaired too.


Replace components and treat power supply section.


Audio section with standard components.


After cleaned & replaced.




Seem JBL audio equipment have higher quality than we think before.

That's why some of Japanese guy still using these with their vintage JBL speaker systems.

Cheers if you are JBL fan and find them in reasonable price.