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Another USSA-5 Build and Review
Another USSA-5 Build and Review
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Old 24th June 2018, 02:34 PM   #1
bvtrinh is offline bvtrinh  United States
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Default Another USSA-5 Build and Review

Just like ggetzoff, I had read sparse reviews about the USSA-5 here and there but from what I read, piqued my interest. I contacted Fab to see about purchasing a pair of boards but was saddened when he informed me he did not have any boards for sale. Instead, he kindly offered to give me a pair of boards with only one condition: I build and provide a review of the amp. I have been occupied by other things and have not kept to the timeline I agreed to. That changed after I saw ggetzoffs post which reminded me to stop being lazy and complete the amp. I just need to complete the power supply in order to test the amp modules per instructions. Then I need to finish the chassis, get it powder coated, finally assembly and review!

Here the boards have been assembled for a few months now. I also have it on the heatsinks.
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Old 24th June 2018, 02:48 PM   #2
e_fortier is offline e_fortier  Canada
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Another USSA-5 Build and Review
Looking forward for your review.

I had the chance to deal w Fab on many occasions and he’s a very generous and kind person.

Good luck w your amp.
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Old 24th June 2018, 05:06 PM   #3
poseidonsvoice is offline poseidonsvoice  United States
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Another USSA-5 Build and Review
Hi!

Looking good! Love the heatsink color!

What are the diameters of the test point holes on these pcb’s? 0.040 inches or 0.062 inches?

Thanks,
Anand.
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Last edited by poseidonsvoice; 24th June 2018 at 05:10 PM.
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Old 24th June 2018, 07:30 PM   #4
fab is online now fab  Canada
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Another USSA-5 Build and Review
Hi
Thanks for interest and post

You seem to have nice and big heatsinks which makes it perfect to increase bias furthermore and especially if you have 4 ohms speakers to increase class A power. Or you can also slightly increase PSU voltage to get a little more power in class AB.

From your pictures I seem to notice a possible mistake for P2 and P4 which value seem to reversed. P2 should be 10k (103) and P4 should be 1K (102).

Remember that if you follow the manual and test each mounted section (CCS, input stage, medium stage, output stage) one at a time you normally get a working amp board at end of test procedure. Step-by-step testing makes it easier I believe.

Looking forward to seeing the final assembly (internal and outside).

Good luck
Fab
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Old 24th June 2018, 07:41 PM   #5
zman01 is online now zman01  Bangladesh
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Another USSA-5 Build and Review
Nice to see another USSA 5 build underway. And the color of the heat-sinks should make for a pretty distinct looking chassis.

Good luck with the build and keep the updates coming.
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Old 24th June 2018, 10:03 PM   #6
bvtrinh is offline bvtrinh  United States
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Quote:
Originally Posted by nycavsr2000 View Post
Hi!

Looking good! Love the heatsink color!

What are the diameters of the test point holes on these pcbs? 0.040 inches or 0.062 inches?

Thanks,
Anand.
Hello and thank you! Im not sure how big the holes are. The pins I soldered on wobbled in the hole prior to soldering. Perhaps Fab or someone can chime in.

Bao
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Old 24th June 2018, 10:09 PM   #7
bvtrinh is offline bvtrinh  United States
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Quote:
Originally Posted by fab View Post
Hi


From your pictures I seem to notice a possible mistake for P2 and P4 which value seem to reversed. P2 should be 10k (103) and P4 should be 1K (102).


Looking forward to seeing the final assembly (internal and outside).

Good luck
Fab
Hello Fab,

They are definitely reversed! Thank you for the catch! Im at the point in the manual where I start adjusting the current sources and am glad you noticed that before I proceeded.

I probably will run higher bias and see how it sounds!

Bao
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Old 24th June 2018, 10:56 PM   #8
Project16 is offline Project16  France
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Quote:
Originally Posted by nycavsr2000 View Post
Hi!

Looking good! Love the heatsink color!

What are the diameters of the test point holes on these pcbs? 0.040 inches or 0.062 inches?

Thanks,
Anand.
The test point holes are of diameter 0.040 inches.
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Old 26th June 2018, 05:01 PM   #9
pinnocchio is offline pinnocchio  Canada
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Those are nice big heatsinks! You should be able to go for 1.3A

Congrats on your build!!

Do
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Old 10th November 2018, 02:45 PM   #10
Hicoco is offline Hicoco  France
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Another USSA-5 Build and Review
Quote:
Originally Posted by bvtrinh View Post
Hello and thank you! Im not sure how big the holes are. The pins I soldered on wobbled in the hole prior to soldering. Perhaps Fab or someone can chime in.

Bao
Hi bvtrinh, nice and congrats could you share the test point type or post a link were you find it,
Thanks
FR
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