pinnocchio
Irish steady hands technique is good until the bottle/PCB ratio is bellow 1:10 at about 1:1 it makes opposite what it ment to do
Received missing parts for MiniPSU, soldered them, powered UP, no fire, no smoke --> happy.
Have made some YT video too:
YouTube
Mile
Nice build but for some reason I do not like the cables all over the chassis + signal wiring/ribbon going around/under the transformer.
For prototype build it is very easy to use 1,5/2,5mm^2 solid core wire, just cut, align and solder, no meas at all.
Regards
Peter
Irish steady hands technique is good until the bottle/PCB ratio is bellow 1:10 at about 1:1 it makes opposite what it ment to do
Received missing parts for MiniPSU, soldered them, powered UP, no fire, no smoke --> happy.
Have made some YT video too:
YouTube
Mile
Nice build but for some reason I do not like the cables all over the chassis + signal wiring/ribbon going around/under the transformer.
For prototype build it is very easy to use 1,5/2,5mm^2 solid core wire, just cut, align and solder, no meas at all.
Regards
Peter
Attachments
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Some months ago, I built Fabs USSA-5 class A amplifier on a very nice black PCB designed by Project16 and Alex.
The USSA-5 turned out to be an excellent amplifier that do most things very well, but what specifically impressed me, was the smooth and detailed highs and the big soundstage. I was curious about the other USSA iterations, and several members from diyaudio.com recommended the USSA-3, which is a simpler design than the USSA-5.
The USSA-5 PCB can be used for USSA-3 amplifier, and Fab has produced an excellent building manual, that walks you safely through the build. I finished my USSA-3 about a month ago, so I have had a good long listen before posting my impressions. I have compared the sound of my USSA-3 to the USSA-5 and Bonsais SX-Ovation.
I am running all my amplifiers on completely identical power supplies, so the differences I am experiencing can only be ascribed to the circuit design and my choice of components.
The USSA-3 has a very full and natural sound. All well recorded acoustic instruments will be reproduced in a very realistic way – almost tube like. Where solid state amplification excels in dynamics and detail, they often have a sort of hidden "whitish" glare that is – more often than not - less natural sounding than what a good tube amplifier can do. Many good solid-state designs are somewhat tilted towards a bright sound reproduction, that highlights details and recording artefacts like studio walls and such. I think, too many audiophiles are focusing more on details and soundstage when choosing their system, instead of asking themselves the important questions: "Can this system really reproduce the nylon strings on a Spanish guitar? Can it reproduce the left side of a Steinway grand piano in a way that energize the room? Does this system reproduce the warm bloom of a bass solo on jazz recording?" The USSA-3 do ALL these things more convincing than the other amplifiers I have built (that includes several Pass First Watt amplifiers)
During the last couple of months, I have been swapping between my USSA-5 and my SX-Ovation, having a tough time deciding on which amplifier I preferred. Where the USSA-5 excelled on finesse and detail, the SX-Ovation was a bit more dynamic with better lows, but some rough edges here and there. Somehow the USSA-3, with its simpler input stage and smaller amount of feedback, comes across as the more musical of the three designs.
The highs of the USSA-3 are pleasing and smooth and the bass is mighty fine too. The bass has a ”looser” quality than the USSA-5 due to a lower damping factor but is somewhat similar to the full BJT bass of the SX-Ovation. When listening to the USSA-3 you stop focusing on all the audiophile artefacts of a good recording, and just enjoy the wonderful sounds flowing towards you from your loudspeaker. The sound is big and very much full-range.
I can only recommend that all fans of the USSA-5 also build the USSA-3. I am pretty sure that you will be pleased and surprised. I want to thank Fab for sharing this design, and as always, his building instructions are second to none.
There has already been several group buys for the USSA-5 PCB on the Quebec DIY audio forum, and I am sure Fab will do another run of PCB’s if the demand is there – and it really should be. Buy the PCB – and go build yourself an USSA-3 or an USSA-5. Both designs will reward you in the most impressive way, but for me in my current setup the USSA-3 is the preferred option
The USSA-5 turned out to be an excellent amplifier that do most things very well, but what specifically impressed me, was the smooth and detailed highs and the big soundstage. I was curious about the other USSA iterations, and several members from diyaudio.com recommended the USSA-3, which is a simpler design than the USSA-5.
The USSA-5 PCB can be used for USSA-3 amplifier, and Fab has produced an excellent building manual, that walks you safely through the build. I finished my USSA-3 about a month ago, so I have had a good long listen before posting my impressions. I have compared the sound of my USSA-3 to the USSA-5 and Bonsais SX-Ovation.
I am running all my amplifiers on completely identical power supplies, so the differences I am experiencing can only be ascribed to the circuit design and my choice of components.
The USSA-3 has a very full and natural sound. All well recorded acoustic instruments will be reproduced in a very realistic way – almost tube like. Where solid state amplification excels in dynamics and detail, they often have a sort of hidden "whitish" glare that is – more often than not - less natural sounding than what a good tube amplifier can do. Many good solid-state designs are somewhat tilted towards a bright sound reproduction, that highlights details and recording artefacts like studio walls and such. I think, too many audiophiles are focusing more on details and soundstage when choosing their system, instead of asking themselves the important questions: "Can this system really reproduce the nylon strings on a Spanish guitar? Can it reproduce the left side of a Steinway grand piano in a way that energize the room? Does this system reproduce the warm bloom of a bass solo on jazz recording?" The USSA-3 do ALL these things more convincing than the other amplifiers I have built (that includes several Pass First Watt amplifiers)
During the last couple of months, I have been swapping between my USSA-5 and my SX-Ovation, having a tough time deciding on which amplifier I preferred. Where the USSA-5 excelled on finesse and detail, the SX-Ovation was a bit more dynamic with better lows, but some rough edges here and there. Somehow the USSA-3, with its simpler input stage and smaller amount of feedback, comes across as the more musical of the three designs.
The highs of the USSA-3 are pleasing and smooth and the bass is mighty fine too. The bass has a ”looser” quality than the USSA-5 due to a lower damping factor but is somewhat similar to the full BJT bass of the SX-Ovation. When listening to the USSA-3 you stop focusing on all the audiophile artefacts of a good recording, and just enjoy the wonderful sounds flowing towards you from your loudspeaker. The sound is big and very much full-range.
I can only recommend that all fans of the USSA-5 also build the USSA-3. I am pretty sure that you will be pleased and surprised. I want to thank Fab for sharing this design, and as always, his building instructions are second to none.
There has already been several group buys for the USSA-5 PCB on the Quebec DIY audio forum, and I am sure Fab will do another run of PCB’s if the demand is there – and it really should be. Buy the PCB – and go build yourself an USSA-3 or an USSA-5. Both designs will reward you in the most impressive way, but for me in my current setup the USSA-3 is the preferred option
Attachments
Having build both versions of the USSA you are talking about (plus a couple more before that), I can only agree with you. At the moment, the USSA 5 is my main amplifier, the USSA 3 is fully assembled but just missing the final chassis which I'm working on.
You seem to be enjoying the amp which makes me very happy for you and Fab. He gave so much time and attention to detail for these amplifiers, gave detailed instruction manual and lots of help on the French forum. Everyone should try these amps.
Here's my version of the USSA 5
Amplificateur USSA: Dans le ventre de la bete - construction par Pinnocchio - Page 7
Thanks
Do
You seem to be enjoying the amp which makes me very happy for you and Fab. He gave so much time and attention to detail for these amplifiers, gave detailed instruction manual and lots of help on the French forum. Everyone should try these amps.
Here's my version of the USSA 5
Amplificateur USSA: Dans le ventre de la bete - construction par Pinnocchio - Page 7
Thanks
Do
Hello Do,
It was your praise of the USSA-5 that originally sparked my interest. You had built and listened to so many well-known amplifiers, and the fact that you preferred the USSA-5 made me curious.
I attached a photo of my final build of the USSA-3.
I totally agree with you, everybody should try these amplifiers.
It was your praise of the USSA-5 that originally sparked my interest. You had built and listened to so many well-known amplifiers, and the fact that you preferred the USSA-5 made me curious.
I attached a photo of my final build of the USSA-3.
I totally agree with you, everybody should try these amplifiers.
Attachments
Hey Do,
Yes, I am running my transformer section in a separate chassis with chokes (CLC). It is a heavy solution that takes up a lot of space, but that way I can use the transformer section on several amplifiers.
I built the USSA-1 and the USSA-5 and these amplifiers are an acoustic treat, so it is logical that I will embark on the construction of the USSA-3 following the encouraging comments.
You definitely should build the USSA-3. You will not be disappointed
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repair and improvement of an older project
I’ve been repairing and improving previous builds lately. Nothing seems to work great the first time.
This is several improvements to a preamplifier I built about a year ago, post # 5082. Changes include.
· The original build had the PCB from the NAD P100 phono preamp. It had some bad connections, so I replaced it with and Elliott Sounds Product phono preamp (P06) http://sound.whsites.net/project06.htm and a subsonic filter (P99) http://sound.whsites.net/project99.htm
· I damaged the power supply with a careless wiring mistake. So I rebuilt it, and added 0.4A fuses.
· Overall I rearranged things to make the wiring more neat and tidy.
1. Subbu DAC V3.0
2. Subbu DAC power supply
3. Twisted Pear USB DAC
4. Elliot Sounds Product power supply, P05B
5. Elliot Sounds Product preamplifier, P37
6. Elliot Sounds Product phono preamp, P06
7. Elliot Sounds Product subsonic filter, P99
8. Ground loop interruption circuit
9. Gold Point selector switch
10 Gold Point volume control.
I’ve been repairing and improving previous builds lately. Nothing seems to work great the first time.
This is several improvements to a preamplifier I built about a year ago, post # 5082. Changes include.
· The original build had the PCB from the NAD P100 phono preamp. It had some bad connections, so I replaced it with and Elliott Sounds Product phono preamp (P06) http://sound.whsites.net/project06.htm and a subsonic filter (P99) http://sound.whsites.net/project99.htm
· I damaged the power supply with a careless wiring mistake. So I rebuilt it, and added 0.4A fuses.
· Overall I rearranged things to make the wiring more neat and tidy.
1. Subbu DAC V3.0
2. Subbu DAC power supply
3. Twisted Pear USB DAC
4. Elliot Sounds Product power supply, P05B
5. Elliot Sounds Product preamplifier, P37
6. Elliot Sounds Product phono preamp, P06
7. Elliot Sounds Product subsonic filter, P99
8. Ground loop interruption circuit
9. Gold Point selector switch
10 Gold Point volume control.
Attachments
ALPHA 20W Class A
Playing now wonderfully through my 10F/8424 RS225-8 transient perfect FAST speakers:
Playing now wonderfully through my 10F/8424 RS225-8 transient perfect FAST speakers:
