[project86]

I admit the dual 3-pin combo jacks that also accept 1/4" TRS is kind of nice. But for strictly balanced use I hate that style.... so there's no pleasing me I guess. 

 

[jacal01]

No no no.  Au contraire.  We chased that issue pretty good on the HiFi-M8 thread when we were voting on its connectors, and the consensus is that the 4-pin XLR much much preferred over the dual 3-pin XLR for headphone cable use, for just that weight/bulkiness aspect.  Most guys there using the balanced headphone configuration are now outfitting their HP cable with the 4-pin connectors, and having short cable adapters made for when they confront a dual 3-pin situation.
 
In fact, the RSA connector was/is promoted as an M8 option, also for that reason, and in fact the mini 4-pin XLR connector turned out to be the most preferred for portable use, and was much bemoaned because it wasn't included in the original member voting poll.

 

[project86]

I guess that "advantage" isn't really true now that I think about it. You either have dual 3-pin XLRs that double as TRS jacks, or else a single 4-pin XLR along with a dedicated TRS jack. Either way, two front panel holes.

 

[jacal01]

That's right.  The panel real estate requirements stay about the same.  The only real advantage is the size of the connector(s) at the end of your headphone cable.

 

[PETERCALV]

  Just a quick update that Questyle will be sending me a replacement CMA800 after the current Chinese Bank Holiday. They tell me it is a modified design with extra outputs (don't know what yet) and a mono switch.
 
I will keep you posted when it arrives.

Good news! The replacement amp is on its way! The model number is CMA800R. Here is an image of it before it was packed for shipping:
 

 
Here are the notes sent to me by Alden:
 
1. This is the upgraded version, model name is change to CMA800R, "R" means "Reference". With the full balance function, it will be a reference for not only our HP amp, but also, I am confident for most HP amplifiers.
2. The front panel added "Full Balance Output", and "Mono/Stereo" option. Switch to "Mono" option, you can connect "Full Balance output" to listen Left /Right channel, function as Mono amplifier, so full balance will need a pair of CMA800R. You can use a Pre-amp to control it, there is "Pre-amp" input on rear panel.
 
Looks interesting! It should be with me in a few days hopefully.

 

[zenpunk]

The XLR output  seem to only have three pins and there is only one so not too sure how it could be a balanced design???

 

[jacal01]

I like the way Questyle is aggressively developing their product for the global market.
 
I see the new kids on the block between the volume knob and the SE headphone outputs.  In fact, if you look at the amp interior photo linked to the embedded image above, you can see that it's still of the old style CMA800.
 
The mono/stereo switch is somewhat confusing.  Mono position means that you need 2 CMA800R amps to get left channel/right channel function, as in mono blocks?  Stereo is SE?  Is that a single 3-pin XLR connector or a 4-pin?  Can you tell?
 
I wonder if the CMA800R THD specs have changed as well...
 
This just in...  zenpunk thinks it's 3-pin.

 

[project86]

I haven't gotten around to asking Alden about it, but the earlier post does make sense - single 3-pin XLR output, dual CMA800R units required for balanced listening.... kind of like the new Woo monoblocks. I guess the volume control no longer applies when using it in that way? Interesting.
 
In other news, I just received the HiFiMAN HE-6 in the mail. Curious to see how the CMA800 handles it - Alden said he had not tried it, and was unable to locate a dealer in the area who carried it. Apparently HiFiMAN is not super popular in that area, or maybe they all just have HE-400 and HE-500 but no HE-6. 

 

[jacal01]

That's not as outlandish as it sounds at first blush.  If they keep their present pricing structure, you can have a true balanced output architecture via dual mono amps for about $3K.  Rack space could get to be an issue tho, especially in conjunction with a preamp feed.  I sorta wish that they would have rotated their amp housing 90° for the balanced mono model, like they did for the CMA600.
 
That's interesting about the HE-6 unavailability.  You would think given their relative proximity... But who knows?

 

[project86]

  That's not as outlandish as it sounds at first blush.  If they keep their present pricing structure, you can have a true balanced output architecture via dual mono amps for about $3K.  Rack space could get to be an issue tho, especially in conjunction with a preamp feed.  I sorta wish that they would have rotated their amp housing 90° for the balanced mono model, like they did for the CMA600.
 
That's interesting about the HE-6 unavailability.  You would think given their relative proximity... But who knows?

 
 
Yep, from their experience, HiFiMAN is not that popular in their area. Not sure exactly what "their area" encompasses though.... could just be a small regional thing, or their circle of headphone enthusiasts. 
 
The good news - spent some time with the HE-6 on the CMA800 today, fed from their QAS192 DAC. Wow. That's a top level rig right there. Very dynamic and very high resolution. I get comfortable, fairly loud levels when I turn the knob to around 12 o clock or maybe 1 for more quiet recordings. I could go to maybe 2 or 3 for super soft jazz or classical, but the dynamic peaks might blow me away. And I didn't hear any evidence of clipping whatsoever, or running out of steam in any way. Have to go back and forth with the AURALiC Taurus mkII for comparison since that's an amp confirmed to drive the HE-6 very well, but so far I'd say CMA800 is very much up to the task. 

 

[PETERCALV]

Yes, Alden has confirmed to me that they can be used like monoblock headphone amplifiers. I wanted to clarify that I could use two of them with either my Eximus DP1 or Naim DCA V1. He has stated that is how they are meant to be used.
 
I would imagine then, that Questyle will now have to bring out a DAC with built in preamplifier to fill in the gap?

 

[jacal01]

Maybe.  The issue with integrated DAC/amps right now is that DACs seem to be evolving at a fast clip these days and amps and preamps not so much.  Perhaps the preamp circuit is not much of an add-on.  Separate preamps are generally about I/O signal selection as much as anything, anyway.
 
That's encouraging news about the HE-6 headphones.  There's a resident crowd that seem to think that planars are best driven by speaker amps.

 

[jacal01]

It occurred to me that the obvious balanced amp configuration is stacked, not side-by-side.  Check to see if the CMA800R has dimples in its top cover to match the cone legs seating arrangement on its bottom. That would be a telltale.

 

[project86]

Doesn't appear so from that pic. I used the CMA800 stacked on the CAS192, and the spiked feet seemed like a liability, so now I use some sorbothane puck thingies under the spikes. Have a set under the CMA800 too, just to protect my shelf.

 

[jacal01]

Good suggestion.  I hadn't really given much thought to the CMA800 cone feet apices digging into my cherry hardwood shelf, I guess because the weight isn't there with a single amp (~3-4 kg?).