FSSA amplifier build thread with review

Hi
10 pcbs (5 pairs) is about 8$ USD for each pcb (pcb+ shipment to my house +custom fee). To be Added to that is shipping price to your house.
More pcb and price is cheaper.

Fab
If you’re happy to make it happen then if you could supply me with 2 sets (no harm in me having a spare pair incase I make a mistake!) and the others who have requested PCBs. If there are any PCBs left over out of a small group buy then I am happy to pay for you to keep them for any future experiments or whatever you would like to do with them - thanks for your great work. Just send me a PM and I’ll wire you the cash to support this.
 
I think the Diyaudio store is already sold out now for the matched quad...🙄
You will have to rely on other sources.

But the matched octet is still available. Maybe if one bought that he could sell it to another user? Like a micro-group buy 😀. A little bit more expensive unfortunately.

@fab: Is there a BOM you could send us? I'd like to create a basket at digikey for the components...
 
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I've just started collecting parts and PCBs for a new AB class relatively high voltage amp (45-50V) and I'm realizing that I've got the NOS Toshiba JFETs and Mos while I can easily buy the Profusion LatFet.
I'm a very slow builder, owing to the limited amount of time I can dedicate to this gorgeous hobby, but, if you can live with it, I'd be glad to add my name to the list for this promising amp.
I'd also add the Sanken drivers to compare them with Toshiba Mosfets ... and decide for the best!.
Many thanks

AnthonyA . 2 sets fssa and 1 set ussa
nfsgame - 1 set FSSA
Vunce - 1 set FSSA
Stretchneck - 3 sets fssa and 1 set ussa
ClaudeG - 1 set FSSA with Sanken
meanie - 1 set FSSA1 (toshiba driver)
zman01 - 1 set FSSA
touchdown - 1 set FSSA with Sanken
 
Brainco...... x2 stereo sets (4 PCB) FSSA for TOSHIBA outputs

AnthonyA . 2 sets fssa and 1 set ussa
nfsgame - 1 set FSSA
Vunce - 1 set FSSA
Stretchneck - 3 sets fssa and 1 set ussa
ClaudeG - 1 set FSSA with Sanken
meanie - 1 set FSSA1 (toshiba driver)
zman01 - 1 set FSSA
touchdown - 1 set FSSA with Sunken

GENERAL:
I have a spare set of USSA 5.4 Boards Available at cost + UK/EU postage.
 
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@meanie thanks for the remark

I don't have both schematics/board layouts on hand but if the changes are related to the pinout of drivers and some cap/resistors around, I could easily make a hand-made daughter board to adapt the different drivers. If it's not feasible, I'm not interested in the Sanken since I only have matched Fets/Mosfet drivers for one amp/2 channel boards.

In case, Fab could suggest if it's doable or not ...
 
Hi

Pcb:
For clarification the FSSA pcb can receive both the Sanken BJT and Thoshiba Mosfet drivers without changes except some resistors values. The Sanken and Toshiba mosfet have a compatible pin out.
This is the USSA and FSSA that use different pcb.

BOM:
I have a preliminary Annotated (from one of the first builder ) build manual version and I could make a clean-up version this weekend to share the BOM. Have in mind that it is not at all as much detailed and comments as the USSA3 or USSA5 manual.

Fab
 
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If you’re happy to make it happen then if you could supply me with 2 sets (no harm in me having a spare pair incase I make a mistake!) and the others who have requested PCBs. If there are any PCBs left over out of a small group buy then I am happy to pay for you to keep them for any future experiments or whatever you would like to do with them - thanks for your great work. Just send me a PM and I’ll wire you the cash to support this.

Hi
Thanks for your offer. With the recent USSA5 pcb offering from Brianco there is only one request for the USSA5 pcb. You can contact me by PM about that.

Fab
 
I'm interested in the Toshiba ones... is it these?

Linear Systems Matched JFETs – diyAudio Store

You have found the input jfet and I stand corrected there is indeed still an octal of the LSK170/LSJ 74 B grade sets available . I had overlooked to check the drop down selection box...🙂
One note is that if IDSS is higher than 9ma then with a higher voltage PSU a small heatsink would be recommended for the input stage 4 transistors. I will add that in the manual.

The Toshiba mosfet driver 2sk2013Y/2sj313Y are TO-220 package and obsolete since a while so only remaining stock from 3rd party. The Sanken BJT version (FSSA2) has been made for that reason.

Fab
 
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Brainco...... x2 stereo sets (4 PCB) FSSA for TOSHIBA outputs
AnthonyA . 2 sets FSSA2 and 1 set ussa 3b+ Ntc, poly cap, sanken+ caddock
nfsgame - 1 set FSSA
Vunce - 1 set FSSA
Stretchneck - 3 sets fssa and 1 set ussa
ClaudeG - 1 set FSSA with Sanken
meanie - 1 set FSSA1 (toshiba driver)
zman01 - 1 set FSSA
touchdown - 1 set FSSA with Sunken
 
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