2sk135/2sj50 amp schematic?

[umut1001]

hi.my friend gave me 6pairs of 2sk135/2sj50 transistors.and i heard that theyre very good and low thd transistors also at low bias..does anyone have a good design?is it worth to build?

[Zen Mod]

maybe not best ..... but certainly decent - designs derived directly from Hitachi ap. notes

if you can't find any , I'll try to find Magnum IA125 schematic I have somewhere

[umut1001]

i like lateral sound.i hope you will find me a good schema. diy brotherhood

[zeonrider]

Originally Posted by umut1001

i like lateral sound.i hope you will find me a good schema. diy brotherhood

Not diy brotherhood, diy Tribe!
regards zeoN_Rider

[dangus]

There were a lot of amps designed around that family of transistors in the '80s. If you have access to electronics hobby magazine back issues you should find a few different designs. I don't remember any being singled out for sound quality. [An amp by H.J. Heckert, reprinted in Audio Amateur, used a bunch in parallel to do 550 watts into 4 ohms. I always thought that would be a nice subwoofer amp.] Googling with the transistor numbers and amplifier should turn something up.

On the other hand, the original transistors have been out of production a long time, so you might be better off selling them to people who need spares.

[umut1001]

i heard that old hitachi laterals has better sound quality than 2sk1058s.so i want to build a nice 50-75watts amp for myself.i dont want to sell them

[umut1001]

Originally Posted by zeonrider

Not diy brotherhood, diy Tribe!
regards zeoN_Rider

we are all sisters and brothers.came from Adam and Eve.Darwin is a lier

[Zen Mod]

Magnum IA125 - output stage

decent sounding .... even if Iq was in range of few tents of mA

if you need more esoteric approach - try on Japanese sites

[umut1001]

yes its very similar to Nico Ras's RAS100 amp.i tried it it was sounding very good but suddenly burned.i didnt understand.my friend also built it and told same problem

[Salas]

''I've got one of these. It's a fabulous amp.
Seeing this thread, I've dug out the original WW articles, June/July/August 1982.''

''Glad you got it fired up.
I must be honest, with my cloth ears, I can't tell my JLH96 apart from my JLHMOS82.
I can tell slight differences between my JLH69 and JLH96.
I do dig it out from time to time, but have not done so for a while.''

JLH69's words about one I revived, I had it first build in the 80's. I recommend it too. Very good amp. Never burned since first build.

The pcb is roughly 125X85mm. Note Q13 is drawn in reverse in the theoretical. 2SJ50's D goes to -V in reality.