Post your Solid State pics here

[fab]

Thank you . No , it's only for testing purpose, or small sub woofer , I don't know yet ....

Hi Alex

I see that you have made a new revision of the pcb (v 0.5)
What are the enhancements?
This small power amplifier is not really meant to perform that well for a subwoofer application compared to other amps since the damping factor is not very high....
Also, have in mind that the specific caps shown on the pictures are not as per the official BOM. You may get a different performance and/or sound...
Nichicon type (as indicated on the pcb ?) for Caps are usually not with very low ESR in general compared to Polymer caps...

Good luck with your build!

Thanks
Fab

 

[planet10]

This small power amplifier is not really meant to perform that well for a subwoofer application compared to other amps since the damping factor is not very high....

It really depends on the woofer and the box it is in.

dave

 

[fab]

It really depends on the woofer and the box it is in.

dave

Ok, thanks for notifying. what is the minimum damping factor you have experienced satisfactorily for a subwoofer and what subwoofer design type is less affected by low damping factor?
Fab

 

[planet10]

Again it depends on the woofer. I expect that a woofer could be designed that is happen with a current amp — damping factor <1.

dave

 

[fab]

Again it depends on the woofer. I expect that a woofer could be designed that is happen with a current amp — damping factor <1.

dave

Wow ! that is a very low damping factor value.

The ussa5 has a damping factor of about 30 to 35 for 8 ohms load (measured at 100 Hz).
What I really meant is that its main attraction is the wide and deep soundstage but in a low frequency application such a subwoofer it would not show...

Fab

 

[planet10]

Any damping factor of about 20 or higher is pretty much the same once you connect a speaker with speaker wire.

dave

 

[dady]

My 'all jfet class A I-V/Pream/Line Amp and Regu' (schematic from Erno Borbely)

Hi, when you get the boards? they are better than Borberly originals pcb
Best Regards

 

[anatech]

Hi Dave,
I would put that number up to somewhere in the 60 to 100 range depending on variables.

-Chris

 

[dady]

Hi Chris again!

 

[anatech]

Hi Esteban!

 

[chalky]

Dummy Load

Got fed up with my scruffy old, ad hoc, dummy load so I decided to build a more durable one. Does 4ohms ( 200W ) or 8ohms ( 400W ), with either 0.1uf, 1uf, or no capacitor in parallel. Monitor output is selectable from directly across the load or via a 10:1 attenuator.

 

[kct]

^^^ very nice and useful addition to the shop.

 

[rottalpha]

USSA 5.0 audio amplifier

fantastic chraftsmanship!

 

[alex mm]

fantastic chraftsmanship!

thank you .

 

[Bigun]

wow, that's a fancy load ! (could add a thermal cutout ?)

 

[chalky]

Yeh, a thermal cut out would be a good addition for soak testing powerful amplifiers. Thanks for the idea; simple to add so I might just do it.

 

[borys]

New year, so time for the new projects, some are smaller and some are bigger.
Mini PSU for audio amplifier, DC protect, delayed ON and fast OFF build in.

 

[smartx21]

New year, so time for the new projects, some are smaller and some are bigger.
Mini PSU for audio amplifier, DC protect, delayed ON and fast OFF build in.

Very nice and useful!

 

[smartx21]

New year, so time for the new projects, some are smaller and some are bigger.
Mini PSU for audio amplifier, DC protect, delayed ON and fast OFF build in.

A lynx-eyed guy (not me) found this...

 

[borys]

smartx21

Thanks a lot.

That is ctrl+C and ctrl+V job hehe.
Corrected files below.

Thanks