[ButtUglyJeff]

  PHA3 as source driving the LC + mdr- z7 is pretty awesome. Musical, top to bottom extension. Doesn't follow the stereotypes as described in general on the forums, for sure...

 
Interesting.  How do you feed the LC from the PHA-3, from the single ended line out, or from the balanced headphone outs?

 

[Hansotek]

one more question for you good folks.....i understand the LC does not come with a power cord,is there any special kind of power cord i need to buy?..can anybody point me in the right direction in order to get the proper cord?

You don't necessarily need any kind of special power cable. I have been A/B-ing a few different cables, however and I have noticed some differences in the sound.

I compared a generic $5 monoprice cable with the $99 Pangea AC9-II. I found the monoprice had a little bit of a grey haze of low-level noise which negatively affected attack, decay and microdynamics. The Pangea fixed this problem, as I hoped. Further comparisons revealed that the soundstage image was somewhat disorganized and inconsistent with the monoprice cable. The Pangea offered a more articulate and well-defined image.

The biggest/best difference I noticed however, was in the overall smoothness. I found the monoprice had a fairly small window of "satisfactory" listening volume between the level of greyed-out microdynamics and slightly-too-harsh transients. I thought the Pangea opened up this window considerably, allowing me to fully enjoy the LC at louder and quieter volumes compared to the monoprice.

I also noticed better extension at both ends and the bass seems a bit cleaner overall.

These weren't night and day differences, mind you - just 1% here and 2% there. I felt the net effect was noticeable... but people have different priorities, and I can certainly understand the appeal of paying $5 vs. $100. It should also be noted that the Pangea AC9-II is nearly wrist-thick and is probably fairly impractical for many people.

I'm going to be adding the Audioquest NRG-3 later this week for another device, but I certainly plan on trying it with the LC and posting impressions here to add to the knowledge base.

 

[XenHeadFi]

  one more question for you good folks.....i understand the LC does not come with a power cord,is there any special kind of power cord i need to buy?..can anybody point me in the right direction in order to get the proper cord?

The Carbon is lighter than you expect. Even the 14AWG Monoprice cable can shift the Carbon around on its own without adding some weight or feet to the Carbon. With larger power cables, you will have to think a little on placement so the Carbon doesn't get pushed or pulled around. I have the Monoprice cable and put the Carbon on some nice rubber feet. Its still easy to move, but has enough friction to not move on its own.
 
It does not require any special power cable. Just one that has the US standard female plug on one end and whatever plug is standard where you are. The Carbon has its own power supply that is universal from "85-250VAC 50/60Hz"

 

[mandrake50]

I decided to check out this hum situation with my LC. My unit is SN 186. First I don't have any ubber sensitive IEMs. So, obviously this is not important for my use. I just grabbed a couple of sets that I use with my portable gear these days. Tthe Fiio EX1 for SE and for balanced, the RE600.  With no signal input (Foobar paused) using SE out I could hear a little hum barely audible starting at 2 O'clock on the volume control. It got quite noticeable at full volume an included a static like component. I then checked with the balanced output. There was zero detectable noise or hum even with volume maxed out at 3X gain. Interesting! I then decided to try to see if it was the amp or inputs that were responsible. I went back to the SE output, cranked the volume to max and unplugged the two XLR cables from the Pulse Infinity. Guess what, the noise went to zero again. In this case it seemed pretty obvious to me that the LC was not producing the noise.
 
Being curious, I decided to plug the SE out from the Infinity into the LC to see what influence using that input may have on the noise. No noise at all at max volume from the SE inputs and output, even at 3X gain, zero detectable noise at max volume. OK, so I switch back to the balanced inputs. The noise was gone, again even with everything maxed out.
 
My conclusion is that, for my unit, with the level of sensitivity of the test IEMs, there is no detectable internally generated noise from the LC. The noise present on the SE output, using balanced in from the Infinity, seems to be the product of a grounding problem between the Infinity and LC. Once I bound the grounds through using the cables between the SE input/output pairs there is no noise.
 
Obviously this worked in my particular setup with my SN 186 LC. There may be differences in individual units. But, this little experiment may give others an idea on something that they may try if having hum problems.
 
Two things to mention here. First, even without the SE cables in place, I would not consider the level of hum to be a problem. The audio level of music playing  at the 2 O'clock position on the volume control (where the hum first became audible) would be more than enough to damage my ears, if not kill the IEMs. In short I would never hear it in use.
 
Second, and a separate subject, but related, I could hear no channel imbalance at any volume setting in either SE or balanced output, nor using either balanced or SE input.
 
I realize that all of this only applies to my unit, but it would seem to indicate that there is no intrinsic problems with the design of the Liquid Carbon.
 
Oh and BTW, I really like the way it sounds.

 

[Peridot]

  I decided to check out this hum situation with my LC ...

 
Out of interest did you start with the LC cold, or had it already been powered up for a period of time?

 

[mandrake50]

   
Out of interest did you start with the LC cold, or had it already been powered up for a period of time?

It had been running for about three hours, playing music into my He 560.

 

[wym2]

 I have also found that when running the amp in 3x mode it does have more punch and a bit more bass. But when I run it in 1x the soundstage gets wider. I hope this FYI is of some help.

the 3x mode shouldn't be used with CIEMs right?  maybe LCD-2
 
but not with the CIEMs/IEMs to avoid damaging the BA drivers?


 
Subjectively, I notice some "congestion" on 3x with complex symphony passages. So I have decided to listen for one week at only 3x and let the LC bake a bit more. 48 hrs and there still seems to me some "thickness" compared to 1x. 
 
MBP → SDragon → Mojo →AQ Big Sur trs →LC → HE400i

 

[mandrake50]

   
Out of interest did you start with the LC cold, or had it already been powered up for a period of time?

I was curious so I cranked the LC up for about an hour into the HE 560. I measured 100 DB average at the ear position using my old trusty RS SP meter with C weighting. The case got only about 2 degrees F higher than normal, but it was well heated. Results did not change.
 
I decided to remove the SE cables as a check. Hum was back. I took a wire with alligator clips on each end and clipped it to the shell of the RCA connectors on one channel at each of the Infinity and LC ends. This achieved the same reduction/elimination of the noise as the RCA cables being connected. To me. an obvious differential ground potential problem. My question is why the shell of the XLR connectors, which I thought should be connected to the shield on the cable and (maybe) chassis ground on both ends, would not take care of the problem.
Ignorance may be bliss, but does not help in understanding problems with electronics. 

 

[XenHeadFi]

My question is why the shell of the XLR connectors, which I thought should be connected to the shield on the cable and (maybe) chassis ground on both ends, would not take care of the problem.

 
Easiest answer is that the shield is connected to only pin 3 and not to the top lug? Or the shield is only connected to one end and not the other?

 

[mandrake50]

Standard OEM XLR cable. I will drag the meter out and check.
 
Well, the cables that I have use an anodized shell. While the shell of the XLR connectors on equipment are usually at chassis ground potential, the anodization  is an insulator. I think that I have some with a bare shell. Will try those next.

 

[bflat]

I asked about this grounding issue some time back on trying to make a RSA 4 pin to dual XLR adapter and was pointed to this website for reference:
 
http://pin1problem.com
 
All that stuff is beyond what I can understand but maybe it will help you guys figure out where the issue may be.

 

[ButtUglyJeff]

Well, I switched DACs from my HiFi-M8 to my CLAS-db (single ended) and its made the world of difference.  I'm about 40 hours in and my MDR-Z7 has never sounded better. Vocals have improved.  Bass has tightened to allow the sub bass to shine more.  And treble has become more "sparkly".
 
I can hear the limitations of portable DACs now and its time for something desktop.  I wonder if Alex's fake DAC is a little less fake?

 

[woodcans]

   
Interesting.  How do you feed the LC from the PHA-3, from the single ended line out, or from the balanced headphone outs?

 
Using the single ended line out. 

 

[Shawnb]

Like others have reported I also have a hum on the SE output. Connected my Shure 535's and below 11 o'clock It's a very faint hum but as you go past 12 o'clock it starts getting louder.
The balanced side is dead silent, so it's just the SE that has the hum.
 
Since this is my first piece of expensive gear is this normal? Should this hum be something I should be sending the unit back for?
 
I also hve an issue with the power button, It seems loose and and when pressed seems to give en extra click before it turns off or on. Not sure if that's something i should be returning over as well.
 
Otherwise it's a great amp so far.

 

[bflat]

  Like others have reported I also have a hum on the SE output. Connected my Shure 535's and below 11 o'clock It's a very faint hum but as you go past 12 o'clock it starts getting louder.
The balanced side is dead silent, so it's just the SE that has the hum.
 
Since this is my first piece of expensive gear is this normal? Should this hum be something I should be sending the unit back for?
 
I also hve an issue with the power button, It seems loose and and when pressed seems to give en extra click before it turns off or on. Not sure if that's something i should be returning over as well.
 
Otherwise it's a great amp so far.

Both are normal - SE noise and the relay during power up. Your LC is fine. You may even hear some channel imbalance on your IEMs at low volume out the SE. All normal. Stick to balanced and enjoy!