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

[Zen Mod]

Do the same with PCB

yes I'll do ......... but only when i check what I have as idea for non-harmful servo

[AR2]

Last year when I heard for the first time J2 at Nelson's place, I was very excited about that amp. Maybe I am too conservative in my expression - I was ecstatic about it. It sounded really great. As I had option to compare it to F5, F3, M2... I was positive J2 was it! Later in the year I build my F5 and F3 and tend to like them a lot. Both of these amps were my favorite, but F5 was kind of ahead of F3. Maybe because I do not have speakers that F3 would shine on, some highly sensitive full rangers that are slightly brighter. F5 on the ones I am using for everyday listening is something I would recommend to anyone. Really great amp.

Last summer when I visited Zen Mod, he had great surprise for me - Babelfish J2 boards and two sets of Semi South JFETS. I do not have to say that I was more than surprised and too shy to accept the gift. But after some "arm twisting" I was off the road to SF with the precious package. I wanted to wait a moment when my workload would allow me to fully enjoy assembly of my present and to give it a proper attention. I got good parts, all Dale resistors, decided to use my Threshold case, and I was ready to go. I was really patient, what is really not my stronger side. Shortly after, I was ready to do the first test run, and to my disappointment it didn't go well. My measurement were weird, my DC offset was bad, amp acted erratically... OK Skype with Zen Mod, again measurements, resistor value changes, parts swapping, still bad... Ha I managed even to confuse Zen Modlu. It took about two weeks of testing until it become clear what was going on. The first problem - LED diodes were off, and they were trowing everything out of balance. Ended up eliminating two and landed on four with what I was getting the right voltage measurement. The other problem I had — during all this trial and error time I managed to burn two Semi Souths. I said OK, I will order more, but lets have one channel working just to hear it. What was left were two badly mismatched Semi Souths. We were able to make it work, but as such it was very unstable and prone to loose balance. I ordered 6 more Sami Souths, 4 to install and 2 just in case. When they arrived, install was breeze, amp acted as it should, by the book. All in all LEDs were the source of all problems.

Finally I am trilled owner of working Babelfish J2. What is left to do is to tap some holes in my case, solve few mechanical issues, and that is it. In the meantime, I will listen. And listening I did.

I was deliberating — do I post my findings? There are not too many people that were as fortunate to receive such a present from Zen Mod, and out of respect for Nelson he is not going to make these boards as a production run. Do I really tell you what I am hearing, or I keep that for myself? It is really hard to be quiet about this. My hand is typing without my decision to do it...

Shortly - this is THE amp. This is the king of the amps. This amp is the ultimate nirvana you have been searching all these years. This is the holly grail of all amps. This is the tube amp that doesn't glow, but sounds like one and than better than one. If anyone tries to take this amp from you, you will be defending it until you have no more limbs to fight with, just like in Monty Python's Holly Grail... but you will still be able to spit.

All my hats down to Nelson and Zen Mod. I am bowing down to the point I am touching ground with my nose. I do not know what Nelson did in his case, and I still do not know, and I know that Choky didn't know what Nelson did, but he was able understand and to add some, and maybe do it in his own way. He is definitely on the same wavelength with Nelson. He added his signatures in the circuit, free of market constraints that Nelson has to respect... And he did it in the big way.

So how does it sounds? It sounds perfect. Nićega previše, Nićega premalo. It sounds right and complete. Singers voice has bass, has mids, has chest. Female singers has bre... upps, chests, you could feel them expanding and shrinking as the air travels through them. Voice is just real. Highs are magical. They are plentiful, but not dry or clinical, they are just magical. This is an amp for any speaker. It has everything in there, so speaker will take it if it can. There is so much base, and midbase you could take shower in it, but it is still not muddy or wooly. It is just right and warm and precise at the same time. That is it, I am not going to say anything about it, someone will come and try to take it. But I tell you I will fight until I could only spit. Zen Modla deserves for this one to be called Zeuss of Audio and to sit above the Olymp, but lets be local and practical, take him out to the Fruška Gora, that will do just fine.

Here are the few shots of my current set up, that is waiting to be housed in the case bellow.

[hifish]

...All my hats down to Nelson and Zen Mod. I am bowing down to the point I am touching ground with my nose. I do not know what Nelson did in his case, and I still do not know, and I know that Choky didn't know what Nelson did, but he was able understand and to add some, and maybe do it in his own way. He is definitely on the same wavelength with Nelson. He added his signatures in the circuit, free of market constraints that Nelson has to respect... And he did it in the big way. So how does it sounds? It sounds perfect. Nićega preciše, Nićega premalo. It sounds right and complete. Singers voice has bass, has mids, has chest. Female singers has bre... upps, chests, you could feel them expanding and shrinking as the air travels through them. Voice is just real. Highs are magical. They are plentiful, but not dry or clinical, they are just magical. This is an amp for any speaker. It has everything in there, so speaker will take it if it can. There is so much base, and midbase you could take shower in it, but it is still not muddy or wooly. It is just right and warm and precise at the same time. That is it, I am not going to say anything about it, someone will come and try to take it. But I tell you I will fight until I could only spit. Zen Modla deserves for this one to be called Zeuss of Audio and to sit above the Olymp, but lets be local and practical, take him out to the Fruška Gora, that will do just fine....

Wonderfull! and many Thanks to the ZM and Papa - The One and Only!!!They've brought so much Joy and Happyness into our lives... :respect: :respect:

[Vix]

Fantasticno!

[Zen Mod]

[sp300b]

[hifish]

:respect:Kudos to that too (in my case!)!

[bata bane]

Excellent description AR2, bravo But if you ask me, somebody put Germanium in those Fet cases, now after listening J2, I am compleatly sure abot that

[generg]

You see Zen Mod,Your Friends AR2 has not forgotten you ........... How do you feel now after this wonderful description. I hope you read it ten times at least .......Best for you

[Zen Mod]

naah ......... he's just over-enthusiastic ......... that's just another Babelfish .besides - I don't like to blush

[sp300b]

that's just another Babelfish .

You old man...It's much more a Shark than a ...fish

[generg]

Poor Zen Mod, he always wanted a babel fish for better understanding between people and now he produced a babel shark.. But who knows what a device can do that produces so much enthusiasm, you see AR2 wants us to defend it at any price if someone wants to take it away........Brothers let us build many babel sharks so there is no robbery .....

[Magura]

Did anybody say "breasts" ? Magura

[Zen Mod]

breasts !

[Sipi]

why ? Aaahh, that's why...

[Sipi]

There's a nice shampoo dispenser

[Zen Mod]

Generg - what's the story with your little Sonidos ?

[generg]

I made only a small test, before they fell on my right foot.........they had some advantages, not so hot highs, and a little bit more volume, but not the fantastic resolution of the Thiel Koax.now they are waiting for a second try, I will give them when I have finished Babel J2 with your boards, I will try them with one and two output devices.......but even for me being retired it is not possible to work on all frontiers at the same time.My wife finds them much more ugly than the ready made Thiel..... so there is still another frontier to consider...ha,ha

[Zen Mod]

you can always bribe that frontier ( don't forget that all FRs are shining after 200 hrs at least ; Sonidos aren't exceptiongood thing is that you don't have shout from start , to fight with)

[sp300b]

Very important thing that I forgot to mention !

Seems to me that BJ2 warming of a heatsinks is much less in comparison to Babelfish, although both of them were using the same supply power and the same operating conditions (Id = 2A).

Most obviously this is thanks to the superb SJEP120R100 design which proves to be high efficiency and minimal loss devices.

Really seems that SIC is very promising new technology.

Fraunhofer researchers succeeded in reducing the power dissipation of conventional inverters by 30 to 50 percent when compared with results obtained using traditional silicon-based transistors.

[Zen Mod]

[sp300b]

Let's check the opinions of the others on Big Diy (link)