UDNeSS, or You don't need Semisouth's

[EUVL]

That mission is accomplished as far as I am concerned.
FirstWatt J2


Patrick

 

[Oneminde]

That mission is accomplished as far as I am concerned.
FirstWatt J2

Patrick

Kewl. I need to go over the thread, something I have not done yet.

This open up the question of does it sound similar (worse, same or better). It is unavoidable.

Great work non the less

 

[EUVL]

I shall not answer questions for subjective impressions.
You'll have to build both and find out yourself.

We'll publish final schematics.
And that will also be it.


Hope someone else will build in the end,
Patrick

 

[Oneminde]

I am working on a preamplifier project, although on a break from the project until past new years, and will need a power amp (or 2-3) so I might be up for testing it.
What is more important is that I am trying to locate an amp that can qualify as a reference amp for my loudspeaker development side of things. In reality, auditioning a loudspeaker on multiple platforms (classes) is unavoidable.
And once you get into diya, we all know that after a while, one starts to collect em .. lol

 

[EUVL]

A reference amplifier should be transparent and not have its sonic signature.
In that sense, these would not be my choice.

If I should have a single-ended reference, it would probably be the SL, or the XELF :
https://www.diyaudio.com/forums/hea...oneer-super-linear-circuit-3.html#post5296415
The XEN XELF Headphone Buffer


Patrick

 

[Oneminde]

I will take a look at the links you provided.

My point was not only reference (neutral) but a span of classes as well as clean and noisy. You want both the clean and neutral sound as well as an amp that has a good handling on even order harmonics or the triode effect.

I am considering building myself the Yamaha M-5000, I like the fact that it uses floating ground which should make it very quiet. Then there is the Honeybadger developed here on diya.

Who says you can only have one amplifier

 

[EUVL]

Study those two first.
They represent two extremes.


Patrick

 

[Oneminde]

^
Will do

 

[EUVL]

After completing stability test and frequency response measurements, this is another mission accomplished.
Maybe somebody will build something during the holidays.




Merry Christmas,
Patrick

.

 

[EUVL]

Here is the V2.0 PCB gerber files.


Patrick

.

 

[EUVL]

And an adaptor PCB to convert 4x 2SK209GR to 2SK389 pin-out.
Of course you can also use 2SK389BL or a matched pair of 2Sk170BL.


Patrick

.

 

[Dennis Hui]

Thank you Patrick.

 

[dBel84]

Excellent, thank you for all the work you put into bringing this to the community

..dB

 

[Oneminde]

Fantastic - Looking forward to building a version. Thanks for the effort.

 

[EUVL]

Bear in mind this is designed for 8R load.
You need to have the right speaker first.


Patrick

 

[Oneminde]

How low will it go ?

 

[EUVL]

First Watt J2 power amplifier | Stereophile.com
The imitant would not be too different.


Patrick

 

[Oneminde]

Better to be on the safe side, so 8 ohm's loads. That should be plenty of headroom down to 4ish ohm's.

 

[EUVL]

You missed the point.
Please read the review.


Patrick

 

[Oneminde]

The J2 rises high above that dispute between cults. Most likely, the First Watt J2 preserves music's vital chi because it's a simple, high-bias, class-A, single-ended, low-feedback design, created by Nelson Pass—one that has no need to impress the mainstream masses or drive 4 ohm speakers.

I don't get the chase for very high sensitivity. I usually listen to my music between 70-85dB, so in that regards, the 25ish watts should be more than enough. But yes, according to Herb, this amplifier has no problems rendering the music with a lifelike sensation with 8 ohm nominal loads.