[francisdemarte]

I'm torn over these two amps. I want to do a budget build and expand in the future. Is it worth it to do a 2CH B22 build or should I don't bother and stick with a regular M^3?

 

[aloksatoor]

upgradability wins in my book unless you specifically want the bass boost feature, lesser heat dissipation and less complexity of the m3

 

[linuxworks]

I have both. in fact, a 2ch b22, 3ch b22 and 3ch m3.

really hard to tell the diff between them, they are both transparent. I use my b22 to drive spkrs (would not do that with the m3, really). but the m3 is more efficient in terms of power and power supply *needs*. m3 is also way easier to debug and build.

to answer you directly, a 2ch b22 is JUST FINE. you won't miss the 3rd channel with your ears, only your test gear (if you have any).

 

[cobaltmute]

cfcubed did a budget b22. You could do something like he did and then add either balanced or the sigma22 later.

 

[linuxworks]

my budget b22: http://www.head-fi.org/forums/f6/rol...ml#post5765067

like I said, nothing at all wrong with 2ch b22.

if I was making an amp for just phones, I'd go with m3. if you DO plan to also power small speakers, go with b22.

 

[ShinyFalcon]

For M³, more opamp choices, easier to adjust gain (adding resistors in series vs changing 4 caps and 2 resistors for β２２), quicker and easier to build, etc.

 

[jcx]

M3 will not give as much Vswing for Hi Z cans since its limited by op amp Vsupply limits and loses a few V because of output/bias device limits

Beta 22 gives up more V but can be run from higher supply V to more than make up the difference

Two channel Beta22 shouldn't be viewed as a compromise - it can beat 3-channel in technical performance

with two dual supplies (dual mono) and "balanced" 4-pin headphone connector (but still running single ended) a two channel Beta22 would only be limited by the Beta22 pcb layout itself - no "3-channel" builds could equal it on the "ground contamination" issue "3-channel" is supposed to improve

if you can find a pwr xfmr with two CT secondaries you can have two isolated dual supplies while paying for only one xfmr - E/U,I split/dual bobbin xfmr have less interwinding parasitic C than toroids

 

[francisdemarte]

Now this is interesting! That's a great looking build Linuxworks!

Seems like 99% of all B22 builds I've seen on head-fi are the 3CH builds. 2CH is almost never considered and I assumed to be a compromise, the populated third board brings up the build cost considerably.

The build cost of the 2CH B22 and M^3 pretty close. The B22 option of being able to power small speakers is also be big plus.

On the other hand I like Audio Technica cans which are low impedance. My ATH-W1000 are only 40 ohms. Is this still going to be worth the effort and cost to construct either of these amps?

 

[Bilavideo]

I'm in awe. Like others, I had always assumed that you were giving up an audible benefit by only going two channel, especially when the M^3 is three channel. This is very exciting news, and I'm glad to hear from those who have heard both (not a huge group out there, so it's a real coup to have it here).

 

[cfcubed]

Quote:

Originally Posted by cobaltmute /img/forum/go_quote.gif cfcubed did a budget b22. You could do something like he did and then add either balanced or the sigma22 later.

Yes and I stumbled into a reason to finish a 4-ch build so I will hear both. My 2-ch sounds pretty good to me tho

 

[linuxworks]

Quote:

Originally Posted by jcx /img/forum/go_quote.gif with two dual supplies (dual mono) and "balanced" 4-pin headphone connector (but still running single ended) a two channel Beta22 would only be limited by the Beta22 pcb layout itself - no "3-channel" builds could equal it on the "ground contamination" issue "3-channel" is supposed to improve

I built 2 s22 PSUs and was toying with the idea of having one PSU per b22 board (still staying with a 2 board config). for speakers which naturally don't share any common wires, this would be as monoblock as you could get

 

[fishski13]

Quote:

Originally Posted by francisdemarte /img/forum/go_quote.gif I'm torn over these two amps. I want to do a budget build and expand in the future. Is it worth it to do a 2CH B22 build or should I don't bother and stick with a regular M^3?

my B22 was a 2CH before a 3CH. i also have an M3. both are excellent, but as much as amps can sound different from one another, they each have a different "sound" to my ears. the choice would come down to personal preference and neither one is "better" than the other.

i wouldn't sweat the difference between a 2CH and 3CH build. although i couldn't A/B them side by side, they both sound great and differences were small to nil.