Burning Amplifier BA-2

[Zero Cool]

the area for C203 large enough for the Elna Silk cap N.P. mentioned?

[cviller]

Originally Posted by Zero Cool

the area for C203 large enough for the Elna Silk cap N.P. mentioned?

Yeah, they are large enough - those mentioned by papa is actually normal radial electrolytics. I'll add a special footprint for those before fabrication.

[joho]

Dear Mr.Pass,

Can you tell us something about the BA-2 sound compared with an Aleph (5) series poweramp?
What are the procs and cons?


Thx in advance,
Johan.

[cviller]

Well I'm not pass and I haven't heard the beast yet, but from the schematics I would think that it is safe to say that it sounds more like a pushpull amp.
You will have less 2nd harmonic distortion and more 3rd. So it will probably sound more analytic and have a better control over the bass.

[tms0425]

Originally Posted by cviller

Hmm.. I have to think about that. The reason for the distance (~5mm) I have chosen is that it fits with many standard terminals. If you can point me to some reasonably priced easy to get terminals of a different spacing than 5mm, I might change it.

BTW: The board is 2.7x5.4 in inches.

Here is what I'm using on your power supply boards. They get a little bit tight as you can see...

[cviller]

Originally Posted by tms0425

Here is what I'm using on your power supply boards. They get a little bit tight as you can see...

I think it might be possible to just add some more holes, so you can connect like you are proposing.

I have added some extra holes for the two 2sj74 option instead of the illusive 2sj109...

Another two things thing that need to be sorted out are 1) the trimpots - they should be accessible when vertically mounted (they kinda already are since they are so close to the edge) and 2) Q203 needs a little heatsinking, which there must be room for.

[Nelson Pass]

I find that I can put 2SJ74's right in the 2SJ109
hole pattern. Am I in error?

[cviller]

Originally Posted by Nelson Pass

I find that I can put 2SJ74's right in the 2SJ109
hole pattern. Am I in error?

In the darker corners of this forum, there is a strong passion for being able to mount the flat parts of to-92 casings together...
It should give slightly better heat transfer between the dies - I would guess the timeconstant to be fairly large though.

[tms0425]

Originally Posted by cviller

In the darker corners of this forum, there is a strong passion for being able to mount the flat parts of to-92 casings together...
It should give slightly better heat transfer between the dies - I would guess the timeconstant to be fairly large though.

You can also use the sweet little dual inline to-92 heatsinks from the group buy but you need to lay them end to end. That way either single j109 or j74 pair fits nicely. Peter did this on the Aleph J boards.

[AR2]

Originally Posted by tms0425

You can also use the sweet little dual inline to-92 heatsinks from the group buy but you need to lay them end to end. That way either single j109 or j74 pair fits nicely. Peter did this on the Aleph J boards.

Yes, that is quite fine, but where to get now those heatsinks?