Hi Fab
Teasing teasing... USSPA 1... and 2! What are the differences?
I am likely to get involved into something I don't really need ;-)
Enjoy your WE
Claude
Teasing teasing... USSPA 1... and 2! What are the differences?
I am likely to get involved into something I don't really need ;-)
Enjoy your WE
Claude
Hi Claude
The difference between USSPA1 and 2 is about the same as between amplifiers FSSA1 and 2....
The Mosfet driver is replaced by darlington Sanken bjt. The result is a similar open loop gain for both USSPA versions. The main advantage is that this bjt is still in production compared to the obsolete mosfet....
Fab
The difference between USSPA1 and 2 is about the same as between amplifiers FSSA1 and 2....
The Mosfet driver is replaced by darlington Sanken bjt. The result is a similar open loop gain for both USSPA versions. The main advantage is that this bjt is still in production compared to the obsolete mosfet....
Fab
Hi Claude,
Very interesting to read that you grow up in Düsseldorf. As a child I live in Mettmann and the last school years i was in Düsseldorf. After that I was a few years at the Wuppertal university. Today I live in Gerresheim a part of Düsseldorf. In which Part did you live? When my calculations are correct then you must be a child of the middle 70?
So we are nearly at the same age, maybe our ways have crossed without knowledge.
I have had a look after your loudspeakers, impressive ones (congratulations), and find following informations about a person who used them with a 15 W tube amplifier (in the response part). Infinity Renaissance 90
So my thought is it could be possible, maybe Fab knows something more about it. If I could help you feel free to ask me.
Schönen Sonntag
André
Very interesting to read that you grow up in Düsseldorf. As a child I live in Mettmann and the last school years i was in Düsseldorf. After that I was a few years at the Wuppertal university. Today I live in Gerresheim a part of Düsseldorf. In which Part did you live? When my calculations are correct then you must be a child of the middle 70?
So we are nearly at the same age, maybe our ways have crossed without knowledge.
I have had a look after your loudspeakers, impressive ones (congratulations), and find following informations about a person who used them with a 15 W tube amplifier (in the response part). Infinity Renaissance 90
So my thought is it could be possible, maybe Fab knows something more about it. If I could help you feel free to ask me.
Schönen Sonntag
André
I was based initialy at Kaiserswerth, then at various locations as that place less and less affordable, finaly Krefeld and Bonn. I remember Gerresheim very well as I went to the French school in Grafenberg. I was born in 1970 and that school was neighbour of a German school, perhaps you were there???
Many thanks for the link, will look at it in detail! And, well, I am talking to Fab, more and more tempted given all the reports inclusive yours already
bb
Claude
Many thanks for the link, will look at it in detail! And, well, I am talking to Fab, more and more tempted given all the reports inclusive yours already
bb
Claude
USSPA PCB
Tomtest and Ernst had their respective pcb shipped today.
I will send you a preliminary build manual this week.
Assanden you are next.
Fab
Tomtest and Ernst had their respective pcb shipped today.
I will send you a preliminary build manual this week.
Assanden you are next.
Fab
May i know if the heatsink dimension of 350x151x50mm is enough for use in this amp ?
Or should i go to the next size up 400x151x50mm ?
Thanks
Or should i go to the next size up 400x151x50mm ?
Thanks
Hi meanie
350mm length heatsink is enough to run 25Wrms (max power) full class A into 8 ohms at lower than 50C. Into 4 ohms you will get half power in class A and more power than 25Wrms in class AB. But who listens to more than 12 Wrms on a daily basis....
Fab
350mm length heatsink is enough to run 25Wrms (max power) full class A into 8 ohms at lower than 50C. Into 4 ohms you will get half power in class A and more power than 25Wrms in class AB. But who listens to more than 12 Wrms on a daily basis....
Fab
Thanks Fab,
I will start posting pictures of my build process soon...
I intend to build it like the Pioneer M22 of the mid 80's design, semi open with torodial and capacitors in the middle section of the wooden platform.
I will start posting pictures of my build process soon...
I intend to build it like the Pioneer M22 of the mid 80's design, semi open with torodial and capacitors in the middle section of the wooden platform.
An externally hosted image should be here but it was not working when we last tested it.
Hi meanie
I had a look at the vintage M22 amp it had an original look, reminds me of McIntosh tube amp with big black transformers where your heat sinks are located.
Keep us posted
Fab
I had a look at the vintage M22 amp it had an original look, reminds me of McIntosh tube amp with big black transformers where your heat sinks are located.
Keep us posted
Fab
Hello Fab, I am looking forward to building the USSPA. Is there a for you noticeable difference in sound between Fet ans Sanken version?
Ernst
Ernst
Hi Ernst
Since I only just recently built version 2 and made a few changes in my system it is difficult for me to respond. I have not done yet an A/B comparison. Normally I like to do it with another passionate like me... however I can already say that I am satisfied with both versions.
Version 1 has been built a few members but not version 2.
Once I can provide more insight on the version 2 I will let you know.
Fab
Since I only just recently built version 2 and made a few changes in my system it is difficult for me to respond. I have not done yet an A/B comparison. Normally I like to do it with another passionate like me... however I can already say that I am satisfied with both versions.
Version 1 has been built a few members but not version 2.
Once I can provide more insight on the version 2 I will let you know.
Fab
Hi Fab,
I finally found the pcb you sent to me.
It has been my wife forgetting them in a drawer.
Now looking forward to build this amp.
Keep you updated,
Frank
I finally found the pcb you sent to me.
It has been my wife forgetting them in a drawer.
Now looking forward to build this amp.
Keep you updated,
Frank
Hi Cixio
Your wife wanted to build it by herself..😛
Or she thinks you have already too many amps....
Fab
Your wife wanted to build it by herself..😛
Or she thinks you have already too many amps....
Fab
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Ha, the old trick where it gets stashed in a pile of mail in a drawer and she forgets about it. Had that happen many times!
My source for the 2SJ 313/2SK2013 has gone unresponsive!
May i know where can i get them now ?
Is match N/P pair a must ?
Many thanks
May i know where can i get them now ?
Is match N/P pair a must ?
Many thanks
Hello
My USSA-5 does not have the 2SJ313/2SK2013 paired and no problem on this subject but if you can find them paired it will be better.
Maybe it is possible to replace them with darlington as on the next FSSA but sel Fab can give you the answer.
I bought my transistors from this seller and they are authentic:
NEW Toshiba Vintage MOS FET 2SK2013 / 2SJ313 1Pair | eBay
You can contact Nicmac on this forum which may have sets available.
😉
My USSA-5 does not have the 2SJ313/2SK2013 paired and no problem on this subject but if you can find them paired it will be better.
Maybe it is possible to replace them with darlington as on the next FSSA but sel Fab can give you the answer.
I bought my transistors from this seller and they are authentic:
NEW Toshiba Vintage MOS FET 2SK2013 / 2SJ313 1Pair | eBay
You can contact Nicmac on this forum which may have sets available.
😉