Comming back to component choices the Fraunhofer Institute has released what they call
a silizium-carbite power transistor. They claim 50% less loss, very high speed and overload margin and temperature stabilty up to 600° celsius. The first amp with that transistor is the Progressive Audio A2. It is a 2 x 100W Class A integrated. It is also claimed that this transistor is mechanically very tough. I spare you the rave about the sound. SiC has a tetrahedric structure found in nature only in metheorites and vulcanic stone. It was used before as grinding powder. It´s Mohs hardness is 9.6 .
a silizium-carbite power transistor. They claim 50% less loss, very high speed and overload margin and temperature stabilty up to 600° celsius. The first amp with that transistor is the Progressive Audio A2. It is a 2 x 100W Class A integrated. It is also claimed that this transistor is mechanically very tough. I spare you the rave about the sound. SiC has a tetrahedric structure found in nature only in metheorites and vulcanic stone. It was used before as grinding powder. It´s Mohs hardness is 9.6 .
In English - Silicon Carbide? Not really new. Infinion is on their third generation process for SiC semiconductors: Silicon Carbide Schottky Diodes - NEW 3G now available! - Infineon Technologies All this does is further compromise the Fraunhofer Institute's questionable credentials. The origin of MP3 making audio claims?
Well, the Infineons are diodes and not transistors. I do not use MP3 much but it is the de facto standart even for musicians. A have a little band and we where searcing for a produces. The producer wanted the music on MP3 to listen in it´s car! That´s a matter of fact. Music for the masses is on MP3. I have not heard before that Frauenhofer has a queationable reputation.....For the majority of people MP3 sounds as good as CD. Not for me but when the bitrate is high enough i could fool you in a double blind test. As far as i know Fraunhofer has also much better algorithms but MP3 got famous. Masking is an intesting concept i think.
What is the crossover frequency and what do you like to crosover rrbadrike ?
What is the crossover frequency and what do you like to crosover rrbadrike ?
Infineon does have a VJFET :
SiCED | Switches
Nelson Pass also have SiC JFETs from SemiSouth in his First Watt J2.
Not sure who is first ......
Patrick
SiCED | Switches
Nelson Pass also have SiC JFETs from SemiSouth in his First Watt J2.
Not sure who is first ......
Patrick
> Not sure who is first ......
It was just a neutral remark / question, and not an accusation.
Someone is selling the SemiSouth for much less than 50USD at the forum.
http://www.diyaudio.com/forums/vendors-bazaar/164271-semisouth-sic-jfet-16-pc-shipping-now.html
I think the lower distortion comes from the much higher transconductance, much like UHC Mosfets (which costs much less, albeit difficult to get).
And with them asking for 20k Euro for a A2 (not even monoblocks) :
Progressive Audio A2 MKII - Vollverstärker - LOFTSOUND Hifi High-End Studio
one can afford quite a few JFETs from SemiSouth.
For me, paralleling 400 small signal JFETs sounds more fun.
Schönen Gruß,
Patrick
It was just a neutral remark / question, and not an accusation.
Someone is selling the SemiSouth for much less than 50USD at the forum.
http://www.diyaudio.com/forums/vendors-bazaar/164271-semisouth-sic-jfet-16-pc-shipping-now.html
I think the lower distortion comes from the much higher transconductance, much like UHC Mosfets (which costs much less, albeit difficult to get).
And with them asking for 20k Euro for a A2 (not even monoblocks) :
Progressive Audio A2 MKII - Vollverstärker - LOFTSOUND Hifi High-End Studio
one can afford quite a few JFETs from SemiSouth.
For me, paralleling 400 small signal JFETs sounds more fun.
Schönen Gruß,
Patrick
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After some research i found that the information i gave you is not accurate.
What Fraunhover was claiming is the world record in efficiency in DC/AC converters with 99.03% on Juli 29th 2009. The transistor they used is the bespoke SemiSouth so they are not the invertors as i thought. Sorry about this.
What Fraunhover was claiming is the world record in efficiency in DC/AC converters with 99.03% on Juli 29th 2009. The transistor they used is the bespoke SemiSouth so they are not the invertors as i thought. Sorry about this.
My measurement on the Tan film chip from Mouser showed pretty good performance at 1/4 rated power but much worse as power increased. I suspect they are good for higher values of resistance (10K or more) than most others, but for lower values I would try metal film in larger case sizes.
If anyone wishes to turn this into a PDF they have my permission for this site only.
I recently ruled out this idea when thinking about how the capacitance parallels up so high.
Without actually doing the work I suspect there is a direct relationship between Rds on and capacitance whether in a single device or an array. Power dissipation would be the big hurdle.
Yes, there is a definate gm/C relationship that depends on process. I think the problem is just the huge C limits the applications. I have found the BF862 and 2SK222 to be the best I can find. I was told the 2SK222 is still in production and available in TO-92 for those that can not deal with SOT-23. It outdoes the 2SK170 in any low current application at 8pF for 10mS @ 1mA.
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