yes surprise, surprise...
dsdjoy had the better eyes and saw the GR on the SK370...
for my simple mind it was clear....
Aleph J about 8mA, one SJ109......
J2 as the name already says, all "double"
so at least 2x 8mA for the two J109......but later I thought Papa took two J109 not to drive better the capacity of the SS, but to double the transconductance of the input J-fets......
later I thought UHHHH with the old frontend of BA-1 Papa drove up to six pairs of IRF with one IRF601 adjusted at 15mA... so why so much mA for the easy to drive SS pair.....
so I slowly accepted the idea of less bias for the j-fets
Accepted. We will go an play at home, until Nelson invites us
This FirstWatt J2 amp is magnificently perfect !
Since Semisouth is not existing anymore, in my opinion there will not be any other amps like this.
Who should be cloning it for commercial purpose (far east or anywhere else) without Semisouth ?
One more reason to buy the original !
This FirstWatt J2 amp is magnificently perfect !
Since Semisouth is not existing anymore, in my opinion there will not be any other amps like this.
Who should be cloning it for commercial purpose (far east or anywhere else) without Semisouth ?
One more reason to buy the original !
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Accepted. We will go an play at home, until Nelson invites us
This FirstWatt J2 amp is magnificently perfect !
Since Semisouth is not existing anymore, in my opinion there will not be any other amps like this.
Who should be cloning it for commercial purpose (far east or anywhere else) without Semisouth ?
One more reason to buy the original !
Semisouth isn't the only semiconductor manufacturer. Other manufacturers follow similar trends in technology, SiC FETs etc. High-end Audio isn't their only market. Maybe another company will buy the intellectual property and continue to make the same parts.
I did not see cloned FirstWatt chassis in any of the usual suspect web sites and forums during the last 12 months.
Nowadays Taiwan is a developed country. Also the democratic rule of presumed innocence should apply to everyone.
We can also take into account - as one possible option - that this Taiwan company makes them for the supplier of Nelson. It can be a copy or can be not. Either way is possible, and until someone prooves the case, I kindly like to suggest to not post accusations against people or whole nations.
Nowadays Taiwan is a developed country. Also the democratic rule of presumed innocence should apply to everyone.
We can also take into account - as one possible option - that this Taiwan company makes them for the supplier of Nelson. It can be a copy or can be not. Either way is possible, and until someone prooves the case, I kindly like to suggest to not post accusations against people or whole nations.
No accusation, but my understanding was that Nelson had this extrusion made. Could be wrong. I think it is important to remember that you would not have the J2 or possibly this extrusion, or even this section of the forum, without Nelson. I try to guard against taking advantage of that in anyway. Not saying anyone is doing so, just saying.
I understand your point of protecting intellectual property. Both USA, Germany and other countries with strong engineering capabilites are damaged by piratery.
However, I also think and saw, that someone who wants to make a profit on counterfeit products is scrupulous.
Pirates do not need original J2 circuit with or without measured and specially selected parts. They could just throw something in that looks like it, sounds half-way decent, make the same case and sell it - pretending it is an original. The counterfeit product quality is usually not in relation to quality of original product. Are there such cases for Audio Amplifier business ?
My feeling is: no
Second group is the hobbyists in China and Taiwan, who like to have chassis that looks 90% like Passlabs chassis. They build X0.2 clones believing they sound like the original (they are far away from that). As I see it, those guys are happy with themselves, enjoying to rebuild what they admire but can not always afford. There are many in DIY Forums in East Asia, but they are DIY guys like we are.
The third ones are copying design, schematics, ideas and use that to build own, commercial products - in different chassis under own brand names. I am talking about industry piracy ! These, I believe, are the more / most dangerous ones, which should not get the schematic and tips/tricks. This group of intellectual property right (IPR) "recyclers" exists in USA, Germany and any other part of the world.
I believe that this dangerous group of IPR-recyclers does not care about FW heatsinks, they use their own.
Only DIY-people who admire Pass/FirstWatt would want to use the same cases/chassis.
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Now I am listening to another J2 inspired amp version of mine.
I had 4 matched, and 4 unmatched semisouth. I mixed them (not random), to get a defined "unmatched" combination.
My J2 inspired amp now sounds a bit 'fuller', more 'bold' and seems to have a bit more bass than original J2. The price I pay for that, compared to original, is a bit less clarity (i.e. clear definition and position of instruments and singers on virtual stage).
My measurements say, I have still less distortion than original. My ears say, I have more than original. Seems there are more things between earth and heaven than THD measurements at 1khz/1W.
Anyway, I noticed:
I like them both. When listening to them, I stop analyzing the amps.
Musik is just there, it sounds so sweet and correct - enjoyable and I notice myself doing other things than analyzing tones - because both amps, being slightly different, are exactly right.
I think that can be called the sweep spot !
I had 4 matched, and 4 unmatched semisouth. I mixed them (not random), to get a defined "unmatched" combination.
My J2 inspired amp now sounds a bit 'fuller', more 'bold' and seems to have a bit more bass than original J2. The price I pay for that, compared to original, is a bit less clarity (i.e. clear definition and position of instruments and singers on virtual stage).
My measurements say, I have still less distortion than original. My ears say, I have more than original. Seems there are more things between earth and heaven than THD measurements at 1khz/1W.
Anyway, I noticed:
I like them both. When listening to them, I stop analyzing the amps.
Musik is just there, it sounds so sweet and correct - enjoyable and I notice myself doing other things than analyzing tones - because both amps, being slightly different, are exactly right.
I think that can be called the sweep spot !
