Sure-Electronics.com class d amps

[dugain]

Hello Wimdehaan
Unfortunatly I cannot send you email because under moderation!.
Could you please send me one with your email adress?
Best regards

[wimdehaan]

my email address is:

whaan [at] lumc [dot] nl

so [at]=@ and [dot]=.

wim

[mhelin]

Has anyone tried running the outputs single-ended like for tweeters requiring less power in active speakers setup. Just connect the positive output to speaker via capacitor, and from speaker to ground (not to the negative output)? Kind of unbridge the amp. I guess that might also help removing some hiss.

[v-bro]

Not a bad idea, however how would the output stage handle cap charging?

Maybe this could be well used for a line array set-up.

[col]

I think mhelin means that the cap would become the high pass for the tweeter?

[mhelin]

Originally Posted by col

I think mhelin means that the cap would become the high pass for the tweeter?

Yes, I guess some cap is needed anyway as the output is at 1/2 Vss I think, because this is a single supply amp.

You could as well have the cap functioning as 1st degree xover. For an example if you use a waveguide like in Zaph's Waveguide TMM (Zaph|Audio) you could use just a 3.9 uF cap for the tweeter and nothing else. For the woofer(s) then you could build an active (or passive line level) xover simulating the needed response (http://www.zaphaudio.com/WaveguideTM...rs-tweeter.gif) which looks like a 12 db/oct @ 2kHz LP. You don't need two woofers / amp channels (used like Zaph did in his passive xover design), just use a single woofer and implement an active (well, you have to buffer the passive filter anyway) variable baffle-step compensation circuit like this:
http://sound.westhost.com/bafflestep.htm

[zougloub]

I have one AA-AB009 (v1.1) and there's a few aspects that I think are worth to share:
+ the sound is good for the price of the board
- the daughter board AA-AB123 cannot be removed properly
"Fortunately" in my case only the top components tend to die
- the TK-2050 are... sensitive, kind of hard to solder
They tend to blow up easily and their main failure mode is "short Vcc to Vdd".
- I'm pretty sure that some components are under-rated for reliable operation
I don't know whether the TK-2050 also blow up in other systems.

In this thread I saw different kinds of daughter boards, they must have evolved...