SemiSouth power Jfets .......... FW J2

[sp300b]

...

Best solution up to now, but commonly not recommended, no pre at all, only shunt attenuator 10k with Charcroft foils in the signal path and short cables to J2.................. simply marvelous!

Most natural sound! May be bass is not totally precise, but all colors of sound are much better, which is more important to me.

I suppose the high input impedance of J2 (220k balanced) and the high gain (20db) and as Zen Mod wrote, the very small input capacitance of J2 makes this direct solution possible.

I recommend to try this possibility also ............... when you have your building of J2 finished. :headphone:

Hello Generg,

Better than this ?

[AR2]

A few tips to J2 builders that might help you in your quest...

• Definitely install protection Zeners, do not omit them "for the better sound"

• Make sure that your Voltage across LED string measured to ground is around 12V. With my LEDs that I purchased brand new from Mouser, 20mA each, I was measuring 17V! Ended up removing two in order to get the right voltage.

• Have closely MATCHED Semi South jFets, will make your life much easier

After that, Dolce Vita

[generg]

Hello Generg, Better than this ?

Hi sp300b, the "poor serbian mans" solution, I don´t have it. I tried the unbalanced, normal version from the DIYforum some months ago with BA-1 and F$ and I liked more my stepped attenuator.But the luxury version of Zen Mod and balanced could be a very good choice, did you hear it already with your J2?

[generg]

A few tips to J2 builders that might help you in your quest...

• Definitely install protection Zeners, do not omit them "for the better sound"

• Make sure that your Voltage across LED string measured to ground is around 12V. With my LEDs that I purchased brand new from Mouser, 20mA each, I was measuring 17V! Ended up removing two in order to get the right voltage.

• Have closely MATCHED Semi South jFets, will make your life much easier

After that, Dolce Vita

Thanks AR2 I will look for the voltage and install the Zeners!

[sp300b]

Hi sp300b, the "poor serbian mans" solution, I don´t have it. I tried the unbalanced, normal version from the DIYforum some months ago with BA-1 and F$ and I liked more my stepped attenuator.But the luxury version of Zen Mod and balanced could be a very good choice, did you hear it already with your J2?

Not yet....I'm using it with Babelfish.Thanks to AR2 for advices

[Tea-Bag]

Not yet....I'm using it with Babelfish.Thanks to AR2 for advices

And PSM OB?

[sp300b]

And PSM OB?

Balanced PSMLS with modified buffer stage

[sp300b]

So, Let's the party begin

[sp300b]

In my case: All PNP transistor used are type BC560C

[sp300b]

LTP Jfets selected and put in their position.Termal paste and heat shrinking tube

[sp300b]

and some more parts soldered

[AR2]

LTP Jfets selected and put in their position.

Termal paste and heat shrinking tube

Uhhhh, jFet manijak

[sp300b]

Uhhhh, jFet manijak

Somebody (JFet) likes it (constantly) Hot

[generg]

These JFets are female they like the treatment at the hairdresser ........ I am so eager to hear your impression sp300b........!Do you still hear your Sonido BLH with the 144 driver?

[sp300b]

These JFets are female they like the treatment at the hairdresser ........ I am so eager to hear your impression sp300b........!

I already know it will be superb....

Do you still hear your Sonido BLH with the 144 driver?

Yes, I do.

[sp300b]

First PCB is almost let's say TEST READY :to_become_senile:p.s. I hate 3mm LED, so I (always) use 5mm LED

[sp300b]

One more picture

[sp300b]

And prove that I'm listening good advices :hi:Safety Zeners....

[sp300b]

ZM, please, take a look and approve this

[sp300b]

And prove that I'm listening good advices

Forgot to mention 100 Ohms for Gate Stoppers, too ;-)

[generg]

100 Ohm is not a must ....ZM advice is starting with 47Ohm and going up and let the ears decide......A good start for you and the gorgeous Sound for you we heard.....

[Zen Mod]

ZM, please, take a look and approve this

yes!especially that part about Philips 12"