[nkk]

So, how would I do this? I have researched it a bit, and come up with the following:

I need 2 sigma11 (aka a sigma22)
I need two PCBs, but how do I do the third channel on each? I would think I just totally ignore it, right?
Of course, a bigger case, or two cases.

Is that all? I feel like it should be much more complicated.

-Nkk

 

[tintin47]

That is mostly it. You need a balanced source, of course. If you want to, you could fill all 3 channels of both boards like normal and have 2x unbalanced amp or a balanced one, depending on what you want. You could also fill only one of the active grounds and have both a balanced an unbalanced amp in one.

 

[nattonrice]

Your questions are answered on the AMB website for the M3:
The M³ Stereo Headphone Amplifier

Go to "Other Options" and then scroll down to "Balanced configurations".

I believe you will want two sigma11 boards (one for each channel) if you intend for a "dual mono" power set up.

 

[nkk]

Wow...I poked around on their page and never saw that. Thanks.

-Nkk

 

[nattonrice]

Hehe yep~
Ti (and Alex Cavalli, Peter Millet, ect) takes care of us pretty good on his diy pages

 

[nkk]

Also, (and this is a stupid question), if I use two s11, I can still use just use plug from the wall? Everything in me says that should be ok, but will that not ruin the dual mono design? How essential is the dual mono pwoer set up? Does it actually effect the sound?

-Nkk

 

[johnwmclean]

You could go totally dual from IEC depending on $$.
A single IEC inlet, two trannies = good enough.

 

[tomb]

You might try contacting cetoole. He built one of the best balanced M3's in existence for Grawk. He may have some valuable insights.

 

[Beefy]

Quote:

Originally Posted by nkk /img/forum/go_quote.gif I need 2 sigma11 (aka a sigma22)

No, this isn't right at all. Two S11's is NOT a S22. But......

Quote:

Originally Posted by nkk /img/forum/go_quote.gif Also, (and this is a stupid question), if I use two s11, I can still use just use plug from the wall? Everything in me says that should be ok, but will that not ruin the dual mono design? How essential is the dual mono pwoer set up? Does it actually effect the sound?

...... I don't personally see the benefit of dual mono for the M3 anyway. For headphone use you will only be drawing 0.6A even with two fully populated amp boards. The S11 can handle this easily with proper heatsinking. And it would be even less if you left the ground channels unpopulated, which is perfectly fine if you mostly use balanced phones.

It isn't like the B22, where the current draw is considerably higher and you need to spread out the heat production.

 

[johnwmclean]

mmm... isn’t this getting into Beta22 territory dollar wise.

 

[johnwmclean]

..

 

[Beefy]

Quote:

Originally Posted by johnwmclean /img/forum/go_quote.gif mmm... isn’t this getting into Beta22 territory dollar wise.

No. I was going to balance my M3, and it would all fit nicely into a single 2U chassis. And a single S11 saves a significant amount of money compared to single or dual S22's.

 

[johnwmclean]

Quote:

Originally Posted by Beefy /img/forum/go_quote.gif No. I was going to balance my M3, and it would all fit nicely into a single 2U chassis. And a single S11 saves a significant amount of money compared to single or dual S22's.

I thinking along the lines of a single S22, and a 2 or maybe 3 board Beta22, obviously balancing has to be weighed up.

 

[amb]

Quote:

Originally Posted by nkk /img/forum/go_quote.gif Also, (and this is a stupid question), if I use two s11, I can still use just use plug from the wall? Everything in me says that should be ok, but will that not ruin the dual mono design? How essential is the dual mono pwoer set up? Does it actually effect the sound?

Even if you use two separate IECs and two power cords, the AC wiring in your house is common... How far do you want to go? Have a separate power generator per channel? lol

 

[johnwmclean]

Quote:

Originally Posted by amb /img/forum/go_quote.gif Even if you use two separate IECs and two power cords, the AC wiring in your house is common... How far do you want to go? Have a separate power generator per channel? lol

I take it on those grounds, you’ve ditched the concept of monoblock design? Just curious...