[Framgeld]

Hi all!
 
I have the Audeze LCD-4 headphones paired with the Chord Hugo TT, and to say the sound is stunning is a massive understatement... but I have been reading various posts regarding the connectivity options that the Hugo TT has, and I am a tad confused. I have read that sometimes (personal opinion?) using balanced XLR provides better sound quality. After shelling out £6200 for new kit, it seems I may as well go "all in" and get the most appropriate cabling too.
 
My LCD-4's came with a single cable:
 

1. 1 x 6.35mm jack plug (into the Hugo TT) <---> 2 x 4-pin mini-XLR (one into each ear cup).

 
The official Audeze balanced XLR cable (the ADZ6B4) is configured as follows:
 

1. 1 x 4-pin male XLR <---> 2 x 4-pin female mini-XLRs.

 
Now this is where I get confused... the Hugo TT has two XLR outputs (assuming Left and Right channels). It appears to me that the official Audeze balanced XLR cable isn't compatible with the Hugo TT without some form of adaptor / splitter, which I would prefer to not have to do.
 
... so if I were to go down the "pure XLR" route, what are the correct XLR cable configurations required?
 
To make things even more confusing, I was reading on the forums here that Rob Watts has confirmed that the RCA outputs are "cleaner" due to there being less components in the path. If this is case... is it possible to connect the Audeze LCD-4's to the RCA connectors instead, or should I stick to using XLR only?
 
Or am I better off just sticking with the 6.35mm jack connection that the LCD-4's were shipped with?
 
Thank you in advance for any advice.
 
P.S. The audio source I am using is a Windows 10 PC via the USB HD connection, using JRiver Media Center 22 via the Chord ASIO driver.

 

[x RELIC x]

Hi all!

I have the Audeze LCD-4 headphones paired with the Chord Hugo TT, and to say the sound is stunning is a massive understatement... but I have been reading various posts regarding the connectivity options that the Hugo TT has, and I am a tad confused. I have read that sometimes (personal opinion?) using balanced XLR provides better sound quality. After shelling out £6200 for new kit, it seems I may as well go "all in" and get the most appropriate cabling too.

My LCD-4's came with a single cable:

• 1 x 6.35mm jack plug (into the Hugo TT) <---> 2 x 4-pin mini-XLR (one into each ear cup).

The official Audeze balanced XLR cable (the ADZ6B4) is configured as follows:

• 1 x 4-pin male XLR <---> 2 x 4-pin female mini-XLRs.

Now this is where I get confused... the Hugo TT has two XLR outputs (assuming Left and Right channels). It appears to me that the official Audeze balanced XLR cable isn't compatible with the Hugo TT without some form of adaptor / splitter, which I would prefer to not have to do.

... so if I were to go down the "pure XLR" route, what are the correct XLR cable configurations required?

To make things even more confusing, I was reading on the forums here that Rob Watts has confirmed that the RCA outputs are "cleaner" due to there being less components in the path. If this is case... is it possible to connect the Audeze LCD-4's to the RCA connectors instead, or should I stick to using XLR only?

Or am I better off just sticking with the 6.35mm jack connection that the LCD-4's were shipped with?

Thank you in advance for any advice.

P.S. The audio source I am using is a Windows 10 PC via the USB HD connection, using JRiver Media Center 22 via the Chord ASIO driver.

The headphone out will be the same quality as the RCA output so don't worry about using the headphone output and losing out on quality. You aren't adding anything extra in the signal path as Chord DACs don't employ an extra headphone amp in the signal path. Chord DACs are single ended and the XLR is there for convenience to feed external balanced amps. The reason balanced sounds better on most other gear is because the balanced topology is better implemented than the single ended topology. The Hugo TT measures better as a single ended device and you should not apply the same thought process as with other gear just to go balanced.

In fact Rob Watts discourages using the RCA and XLR outputs to drive headphones as they are really only meant to feed an external amp. You can read his reply on the matter in these posts from the DAVE thread, which is also relevant to the TT:

http://www.head-fi.org/t/766517/chord-electronics-dave/840#post_12124924

http://www.head-fi.org/t/766517/chord-electronics-dave/1695#post_12355143

The impedance mismatch and the lack of current drive from the XLR will not be good for driving headphones from the XLR outputs. Again, Chord DACs measure much better than almost all other balanced DAC/amps so there is no need to use balanced. One other thing is that the headphones don't care if your source is balanced or not, it's the source gear implementation that you are hearing the improvements from a balanced topology.

Some more reading below (click to read) regarding Rob's single ended implementation vs balanced (from the Mojo thread, but also relevant to all of Rob's DACs):

Spoiler: Rob Watts and John Franks on balanced output

Originally Posted by Mojo ideas View Post

Originally Posted by MrDerrick View Post

Of course the balanced output is going to be better than the Mojo, the Mojo doesn't have balanced output.
No that simply is not correct! A single ended design, done right with a large enough voltage swing will easily out perform a balanced output. Balanced designs are used by some designers to overcome inherent limitations within designs. Usually to overcome substrate noise on the chip that shouldn't be there or to increase the output voltage swing of their amplifiers. We don't suffer those limitation or problems so we don't need a dodgy fix for them. Our measurements clearly show this. Sorry to burst you bubble man.

Balance operation is a fix for problems we don't have. We have no substrate noise and we have plenty of output swing. Single ended done right is far better than a balanced design far less distortion.

Originally Posted by Rob Watts View Post

Originally Posted by agisthos View Post
Rob you should give a definitive 'why SE is better' explanation. Get it over with, because many (most) audiophiles have been biased towards balanced and are not going to understand where you are coming from.

One good argument I heard from the Densen founder (Thomas Sillesen) is that each half of the signwave runs through a series of components that will always have tolerances different from each other, so when combining the signal they will not ever match, causing an increase in distortion (of some kind I cannot remember).

Charles Hanson, of Ayre, who is a proponent of fully balanced equipment, has even stated that for pure sound quality SE will always sound better, but this is on the bench, where the power supply and analog signal stages can be kept physically apart. When putting them in a box he prefers balanced.
Well this is a complex subject, and sometimes a balanced connection does sound better than single ended (SE) - in a pre-power context - but it depends upon the environment, and the pre and power and the interconnect. But the downside of balanced is that you are doubling the number of analogue components in the direct signal path, and this degrades transparency. In my experience every passive component is audible, every metal to metal interface (including solder joints - I once had a lot of fun listening to solder) has an impact - in case of metal/metal interfaces it degrades detail resolution and the perception of depth. So going balanced will have a cost in transparency.

In DAC design, going balanced is essential with silicon design; there is simply too much substrate noise and other effects not too. But with discrete DAC's you do not need to worry about this, so going SE on a discrete DAC is possible, and is how all my DAC's are done. But differential operation hides certain problems (notably reference circuit) that has serious SQ effects; so going SE means those problems are exposed, which forces one to solve the issue fundamentally. In short, to make SE work you have to solve many more problems, but the result of solving those problems solves SQ issues than differential operation hides when you do measurements.

Rob

Originally Posted by Rob Watts View Post

Component count is very important for transparency. Doubling the number of parts in the direct signal path does degrade depth perception and detail resolution.

But there is another problem with balanced operation. Imagine a balanced differential in, differential out amplifier. The input stage is normally a differential pair (maybe cascoded) with a constant current source. Now the input stage is free to move up and down to accommodate the common mode voltage - but the input stage common mode impedance is non linear, and if the common mode voltage has a signal component (it always will have due to component tolerances) then this will create a signal dependent error current, thereby generating distortion. Unfortunately, the negative feedback loop of the amplifier can't correct for this distortion as it can't see the error on the summing nodes. So there will always be a limit to the performance. With SE operation, this problem does not occur, as the differential input stage is clamped to ground.

Now DAC designers are well aware of this - that's why all high performance DAC's use two single ended I to V converters from the current OP of the DAC's, then use a differential to SE converter to create the voltage OP. There are other reasons for doing this as well, as the DAC requires a very low impedance virtual ground for low distortion, and you can only get this using dual SE amps - another problem is RF and its much easier to decouple SE than differentially - this in turn creates a lot more noise floor modulation, making it sound less smooth.

But for me the most important is transparency. I had an amp that had two modes - differential or SE - listening in balanced mode flattened the sound stage depth dramatically,and it sounded harder, less smooth. That said, there are circumstances when balanced operation can be better than SE, for example when you are looking at connecting a pre-amp to a power amp, and what is best depends upon particular circumstances. In short, if SE operation is noisy, try balanced.

Rob

 

[Framgeld]

Relic,
 
Thank you for the detailed response. It also makes sense.
 
Based on all of that, it would seem that the option to go for is:
 

1. sticking with the 6.35mm jack connection that the LCD-4's were shipped with

 
And once again... thank you.

 

[AlanYWM]

  Relic,
 
Thank you for the detailed response. It also makes sense.
 
Based on all of that, it would seem that the option to go for is:
 

1. sticking with the 6.35mm jack connection that the LCD-4's were shipped with

 
And once again... thank you.

 
Yes, if you are basically using the TT without an external amp, then you should stick with the 6.35mm jack. However, if you want to use an external amp (together with the TT) that happens to have balanced outputs, you may then want to have a cable with something like a 4-pin XLR connector. It is up to you. I use an external amp with balanced outputs with my TT and my headphones cables are all with 4-pin XLR plugs.

 

[ubs28]

I believe the XLR output is intended for amplifiers rather than for headphones.
 
So it's best to use the standard cable for your LCD-4 and use it in the headphone output.