[deathg0d]

eugenek, i am planning to get hd800 as well and i have a similar setup as yours so what are you thoughts?

 

[oneplustwo]

You certainly can. It just won't be quite as "dual mono" which many of the hard core people here would prefer. But I'm not sure anyone would be able to tell the difference frankly. With my own, I used a single sigma for a while before my second sigma was in working order and I personally didn't notice a difference myself FWIW. One thing to consider, if you'll be powering speakers, it might be good to split the load between 2 sigmas. Also, make sure you size your trafo(s) accordingly.

By gain of 5, I assume you mean a combined gain of 10? That should be fine.

 

[Beefy]

The concern with having two power supplies for a balanced build isn't for sound quality, or any ideal of your amp being dual mono. It is for heat management on the MOSFETs on the S22. Four boards suck a lot of current, and if your unregulated voltage is high that means a LOT of heat will be generated.

A single S22 powering four boards should probably use larger than default heatsinks, and be very well ventilated.

 

[pila405]

There are some cases / enclosures with heat sinks on the sides, can you recommend me on some good enclosures to do the task?
It doesn't have to look good, just to be built properly and made off aluminum.

 

[oneplustwo]

these are a bit pricey, but look quite nice:

 

[pila405]

But its HUGE! Is there something like that just about half the width?

There are some enclosures which you can attach the heat sniks on the sides to the MOSFET. Do you know what I am talking about?

Look on the photo gallery of the b22 on AMB's site. The one with the red front panel [meant to be used with AKG K1000] - The seconed one after Ti's b22.

 

[oneplustwo]

I don't think it's that much bigger. Were you looking at this one?

If you're doing a three channel and sigma in one case, that's going to be comfortable.

EDIT: Now that I think about it, you're probably doing a 2 channel using one board for each side? In which case, this is kinda big.

 

[pila405]

But the b22 is gonna be in different chassis...I need a enclosure which is half as wide as what you offered. But thank you very much, it is exactly the style I wanted.

 

[EugeneK]

Quote:

Originally Posted by deathg0d /img/forum/go_quote.gif eugenek, i am planning to get hd800 as well and i have a similar setup as yours so what are you thoughts?

I love it. ^.^ B22 + HD800 is more detailed than Auditor + HD800

 

[Magsy]

I've got mine, 4 boards, 1 psu and 120va trafo in a square of 310x310mm but it is stupidly tight. Those cases just look big, a balanced B22 is BIG!

My single psu is ok, it is pretty hot tho but I've been burning it in for 20 nights for 8 hours a night, flat out. Totally fine!

 

[pila405]

But I want the supply to be in different enclosure...

 

[dazzer1975]

got the backplane boards ordered the beta boards and psu boards and the parts available on ambs shop thus far.

still deciding wether to go 2 channel active ground or fully balanced. Going balanced would require an upgrade of my source too, but to diy a beta 22 and not go the whole hog seems a bit silly lol

gotta do some more reading to check out my options before I buy any more parts etc but looking forward to it all.

printed off all the releveant build info bookmarked a few threads here and on headwize so should be ready to go for the summer time when I plan to tackle it.

 

[linuxworks]

Quote:

Originally Posted by dazzer1975 /img/forum/go_quote.gif still deciding wether to go 2 channel active ground or fully balanced. Going balanced would require an upgrade of my source too, but to diy a beta 22 and not go the whole hog seems a bit silly lol

strongly disagree.

balanced is hype for most consumers. its about ego more than anything.

I'll take the opposite view and say that balanced is 'a bit silly' in this context. I may bring my 2ch b22 and 3ch b22 with me to the next meet. I challenge anyone to do a DBT and tell me which was which. I doubt anyone could.

I wish ego would not enter into 'building the biggest' amp. this is not the reason to build 'big amps' (sigh).

 

[m1abrams]

NOTE: I have not built or heard any beta22

I agree with linuxworks that going balanced is probably not going to make much of a difference for most headphone users. One reason that would make me build a balanced beta22 is if I planned on using it for speaker duty where the extra power maybe needed.

 

[linuxworks]

I've been using my 2ch b22 for speaker use (8" tannoy 2way pbm8's) and it seems to fill the room with volume (and bass, too!) before I even get to '11' on my volume control (lol). typical size bedroom, not large living room, though.

I'd go b24 before I'd go balanced on a b22 for spkr use. balanced b22 is VERY expensive and it seems like the b24 is the better choice if you truly are going to drive 'hard' (large) spkrs.

it took me a long long time to even 'concede' to do a 3ch b22

and I did it because the backplane was 'there' and easy to use. to be honest, I never heard any diff on the 3ch version. once you are 'very good' being better does not make the sound any better; only makes your wallet lighter and your stereo rack heavier