[StolenToast]

Supposedly the people at Grace designed the m9XX using an HD800 as their primary reference. So that makes sense.

Woulda sworn it was the X00 given no other knowledge (which I did not have).
 
I do want to say I leave my m9xx in and on always but I notice that it stays warm.  Now, I'm no elecmatrancer (not even an apprentice!) but that suggests to me that when it's idle it draws more power than just enough to power the indicator dot.  And when I say warm I mean warm, not hot.

 

[scorpioh]

Anyone has opened up the m9xx to catch a glimpse of the circuitry? I wonder if electrolytic capacitors are used.

 

[fjrabon]

Woulda sworn it was the X00 given no other knowledge (which I did not have).

I do want to say I leave my m9xx in and on always but I notice that it stays warm.  Now, I'm no elecmatrancer (not even an apprentice!) but that suggests to me that when it's idle it draws more power than just enough to power the indicator dot.  And when I say warm I mean warm, not hot.

Yeah, there's actually a train of thought that DACs sound their best when warm. Don't know if I believe it, but it's a theory that's ouchea.

 

[ViperGeek]

Hey!  Great news!  Additional Grace-blessed power supplies are now available on their website:
 
http://www.gracedesign.com/products/m9XX/m9XX.htm
 
- Dave

 

[ViperGeek]

  I do want to say I leave my m9xx in and on always but I notice that it stays warm.  Now, I'm no elecmatrancer (not even an apprentice!) but that suggests to me that when it's idle it draws more power than just enough to power the indicator dot.  And when I say warm I mean warm, not hot.

 
I can't find the reference ATM, but I developed the distinct impression that the Grace m920 amp runs in Class A mode, which means, the less signal it amplifies, the more power it uses (gross oversimplification, I know).  The m920 gets nice 'n warm too, although not uncomfortably so.  I wonder if the m9XX has the same architecture/Class as its bigger brother?
 
- Dave

 

[Ormia]

Anyone has opened up the m9xx to catch a glimpse of the circuitry? I wonder if electrolytic capacitors are used.

At some point in the discussion found on mass drop, you will be able to find pictures of the internal comments of the m9xx.

 

[Neotribal]

  Hey!  Great news!  Additional Grace-blessed power supplies are now available on their website:
 
http://www.gracedesign.com/products/m9XX/m9XX.htm
 
- Dave

Thanks! Ordered a spare.

 

[scorpioh]

At some point in the discussion found on mass drop, you will be able to find pictures of the internal comments of the m9xx.

Thanks! It's on page 13. Full solid state polymer caps. It's going to last quite a long time. Nice!

 

[fjrabon]

   
I can't find the reference ATM, but I developed the distinct impression that the Grace m920 amp runs in Class A mode, which means, the less signal it amplifies, the more power it uses (gross oversimplification, I know).  The m920 gets nice 'n warm too, although not uncomfortably so.  I wonder if the m9XX has the same architecture/Class as its bigger brother?
 
- Dave

It's a current amp with a custom topology for 0 output impedance.  I think I read somewhere that it's class A from 0-90 and then switches to AB for 90.5-99.5, but please don't quote me on that.

 

[fjrabon]

 
Thanks! It's on page 13. Full solid state polymer caps. It's going to last quite a long time. Nice!

things like this have lead me to be more and more and more impressed with this thing.  It's like every time I actually research some small aspect of it, it turns out to be much more imrpessive than I initially thought.  Like if anything this was probably underhyped due to Michael Grace's trademarked brief and to the point engineer way of speaking.

 

[sheldaze]

Yeah, there's actually a train of thought that DACs sound their best when warm. Don't know if I believe it, but it's a theory that's ouchea.

Unfortunately, that is true.
 
Fortunately, it is pretty minor for most Delta-Sigma DACs.
 
It's a pretty deep rabbit hole when you start considering things like this. But it's pretty simple for me. After I sell my The Element (with ODAC rev B), I will have a single Delta-Sigma DAC in the house, which is the Grace Design m9XX. It has no on/off switch, so it just stays on 

 

 

[EinZweiDrei]

am i double amping if my m9xx is on high power while connect to an external amp through line out?

 

[fjrabon]

am i double amping if my m9xx is on high power while connect to an external amp through line out?

Only if the volume is above 90. 90 is unity gain for a 2V line level out.

 

[JamieCole]

  Unfortunately, that is true.
 
Fortunately, it is pretty minor for most Delta-Sigma DACs.
 
It's a pretty deep rabbit hole when you start considering things like this. But it's pretty simple for me. After I sell my The Element (with ODAC rev B), I will have a single Delta-Sigma DAC in the house, which is the Grace Design m9XX. It has no on/off switch, so it just stays on 

 

 
And @fjrabon - Correct me if I'm wrong... did I read somewhere that Grace was working on a power down function for a future firmware update? 
 
Looking forward to receiving and listening to mine! The pictures of the internals on page 13 over on the Massdrop discussion board are pretty sweet. However, I especially liked the Mini Mouse headphones a few posts prior. 
 

 

[JamieCole]

Ah, this is the post from Will regarding the potential for a sleep/power down function in a future firmware update.  
 
http://www.head-fi.org/t/785553/grace-design-x-massdrop-m9xx-dac-amp-review-first-impressions/225#post_12037569