Hi Stretchneck
Neither my USSA7 nor USSA8 have used the FQ3P but rather obsolete 2SK2013/2SJ313 and 2SD2081/2SB1259 (now more recently obsolete). They could probably be adapted to have the FQ3P but have in mind that both these versions are considered prototypes….
see https://quebecdiy.forumactif.com/t54-ussa-8-turbo-edition-semi-limitee-classe-ab for more info.
Fab
Neither my USSA7 nor USSA8 have used the FQ3P but rather obsolete 2SK2013/2SJ313 and 2SD2081/2SB1259 (now more recently obsolete). They could probably be adapted to have the FQ3P but have in mind that both these versions are considered prototypes….
see https://quebecdiy.forumactif.com/t54-ussa-8-turbo-edition-semi-limitee-classe-ab for more info.
Fab
Your manual is well done. I had commented your manual a few weeks ago on my ipad…..but the file was not save with my comments 😡for an unknown reason….I will have to include my comments again into the document….maybe I can simply provide them in a list by email….
Fab
Fab
I'll put the manual as an editable file in the dropbox this afternoon. Maybe that's easier 🤓...
After one or two verification builds I think it would be the easiest when I upload the gerber files in the thread so that everyone who wants to build a "big one" could order the helper boards by him/herself...
fab and I are exchanging about the documentation. I have to do some graphics to clear the interconnection between the different boards ("wiring diagram") and then it could go into the hot phase...
fab and I are exchanging about the documentation. I have to do some graphics to clear the interconnection between the different boards ("wiring diagram") and then it could go into the hot phase...
Hey guys, I'm in Italy till next monday evening for work. I hope I can finish the package after my return.
Hi Pinnocchio
v 0.8 USSA pcb is a mini version for lower power amplifier to integrate in a small chassis. I use this pcb in my portable all-in-one music server/amplifier. In that case it is for an USSA-4B version. See attached pictures. Useful when I want good sound in a remote location rental cabin in the woods….
Fab
v 0.8 USSA pcb is a mini version for lower power amplifier to integrate in a small chassis. I use this pcb in my portable all-in-one music server/amplifier. In that case it is for an USSA-4B version. See attached pictures. Useful when I want good sound in a remote location rental cabin in the woods….
Fab
Attachments
Sure it can be used as a headphone amp. But in that case I would not install the power ouput transistors and rely only on drivers since they operate at more than 50ma which is quite enough for any headphone in class A region….
For headphone you can also use USSPA pcb with jfet input.
See below this USSA v0.8 pcb used in a preamp with bjt input and only drivers as output. Note the input cap on pcb is bypassed with a wire. However I have used a speaker crossover cap to protect the TKD potentiometer….
Fab
For headphone you can also use USSPA pcb with jfet input.
See below this USSA v0.8 pcb used in a preamp with bjt input and only drivers as output. Note the input cap on pcb is bypassed with a wire. However I have used a speaker crossover cap to protect the TKD potentiometer….
Fab
Attachments
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Great advice, thanks Fab! My headphones are 16Ohm and not very sensitive...
Which DAC did you use in this built?
Which DAC did you use in this built?
Hi baggerbole
in the last shown preamp there is no DAC (it was a previous build several years ago).
in my all-in-one portable amplifier, because of space constraints, it is a raspberry pi hat DAC AK4493 bought on Ali Express.
Fab
in the last shown preamp there is no DAC (it was a previous build several years ago).
in my all-in-one portable amplifier, because of space constraints, it is a raspberry pi hat DAC AK4493 bought on Ali Express.
Fab