[CaptainFantastic]

With my FiiO m11, iPhone and iPad it works just fine. This is so bizarre

You said that your other headphones do not do this when plugged into the THX 798. What is the impedance on the other headphones? Here is why I ask... my experience with the Chord Mojo: I was listening via the Samsung S9 -> Mojo at work for months on my HD-600, HD-650, or HD-660S. These are all 300 or 150 ohm impedance headphones. Then I plugged in the Audioquest Nighthawk (25 ohm impedance). All of a sudden, a buzzing background noise became evident. I posted and asked on the Chord Mojo forum. Turned out (in my case), that this was due to RFI that was audible only on low impedance headphones. With the Sennheisers it was not there - period. In my case, because of the Mojo specifics, this was cured / is cured by turning off 3G.

In your case, I can only venture to guess that the THX 798 is the problem causing the noise but it is only audible with the low impedance MX4s. Do you have another low impedance headphone to plug in? And even then, could the big planar technology (Tesla 1.5 magnet) in the MX4 do this when coupled with that particular amp? Just providing some ideas. Maybe Audeze can provide an opinion. I see that they are viewing this forum right now.

 

[redbaaron]

You said that your other headphones do not do this when plugged into the THX 798. What is the impedance on the other headphones? Here is why I ask... my experience with the Chord Mojo: I was listening via the Samsung S9 -> Mojo at work for months on my HD-600, HD-650, or HD-660S. These are all 300 or 150 ohm impedance headphones. Then I plugged in the Audioquest Nighthawk (25 ohm impedance). All of a sudden, a buzzing background noise became evident. I posted and asked on the Chord Mojo forum. Turned out (in my case), that this was due to RFI that was audible only on low impedance headphones. With the Sennheisers it was not there - period. In my case, because of the Mojo specifics, this was cured / is cured by turning off 3G.

In your case, I can only venture to guess that the THX 798 is the problem causing the noise but it is only audible with the low impedance MX4s. Do you have another low impedance headphone to plug in? And even then, could the big planar technology (Tesla 1.5 magnet) in the MX4 do this when coupled with that particular amp? Just providing some ideas. Maybe Audeze can provide an opinion. I see that they are viewing this forum right now.

I've been using the MX4 with the THX 789 amp all day (for several days) without this issue. Even on high gain there is no hum (high gain is totally overkill on these headphones). Therefore, I believe there is something wrong with CortoLmaltese's setup.

 

[groovyd]

Is a poor ground on the ground shield going to the headphone (outside most ring) from within the amp. It can also happen if your headphone cable ground shield is not very good or not well connected on both ends of the cable (on one side to the amp and on the other side to each driver). I got the same thing using a McIntosh D100 DAC/pre-amp connected to their own McIntosh MHP1000 of all things using their own supplied light blue cable. I was able to fix it by getting rid of their supplied blue cable and instead using a good quality Norne Audio cable but likely any decent cable should prevent it. It was likely due to a bad solder joint within the McIntosh blue cable. If swapping with a high quality cable doesn't fix it the problem likely lies at either the solder joints to the driver inside the headphones (likely to happen with any amp but not necessarily) or most likely a cold solder joint inside your amp between the output amp and the headphone jack. You can also try cleaning the headphone jack of your amp with a q-tip and some rubbing alcohol turned off of course. It doesn't take much to turn the headphone cable into an antenna essentially.

Also try using a headphone cable that is coaxially shielded.

 

[521994]

You will not believe what the issue was. I tried everything and as a last thought was “static electricity”. Yes, static electricity... I Was seating on a synthetic sofa cover which generated a lot of static electricity by rubbing. I removed the cover and there you go, no more noise....

 

[redbaaron]

You will not believe what the issue was. I tried everything and as a last thought was “static electricity”. Yes, static electricity... I Was seating on a synthetic sofa cover which generated a lot of static electricity by rubbing. I removed the cover and there you go, no more noise....

That is very interesting!

 

[521994]

That is very interesting!

Will be cool if someone in the community with scientific background could explain it

 

[sahmen]

Will be cool if someone in the community with scientific background could explain it

Well, in theory, that might sound right, but given some of the so-called "science" I have heard spewed inside this same community, this might not be such a great idea.

I am not trying to impugn anyone's name in particular. I am just referring to such famous debates about themes such as the science of cables, audiophile fuses, or digital devices, digital noise, and the difference they might make or not make. Oh, and the co-relationship (if any) between "scientific measurements" and sound quality...

Just doing my duty as a community citizen by cautioning you to be careful what you wish for, when you ask for "science" in this forum

Of course you may completely ignore my caveat and proceed as if nothing happened, and that would be okay too

 

[521994]

Well, in theory, that might sound right, but given some of the so-called "science" I have heard spewed inside this same community, this might not be such a great idea.

I am not trying to impugn anyone's name in particular. I am just referring to such famous debates about themes such as the science of cables, audiophile fuses, or digital devices, digital noise, and the difference they might make or not make. Oh, and the co-relationship (if any) between "scientific measurements" and sound quality...

Just doing my duty as a community citizen by cautioning you to be careful what you wish for, when you ask for "science" in this forum

Of course you may completely ignore my caveat and proceed as if nothing happened, and that would be okay too

Well, I know exactly what you mean. I am an engineer my self. So if an electrical engineer can share thoughts, these are more than welcome. after all the problem has been solved

 

[Hifiearspeakers]

Well, in theory, that might sound right, but given some of the so-called "science" I have heard spewed inside this same community, this might not be such a great idea.

I am not trying to impugn anyone's name in particular. I am just referring to such famous debates about themes such as the science of cables, audiophile fuses, or digital devices, digital noise, and the difference they might make or not make. Oh, and the co-relationship (if any) between "scientific measurements" and sound quality...

Just doing my duty as a community citizen by cautioning you to be careful what you wish for, when you ask for "science" in this forum

Of course you may completely ignore my caveat and proceed as if nothing happened, and that would be okay too

+1

Multiplied by infinity

 

[paulybatz]

You will not believe what the issue was. I tried everything and as a last thought was “static electricity”. Yes, static electricity... I Was seating on a synthetic sofa cover which generated a lot of static electricity by rubbing. I removed the cover and there you go, no more noise....

Holy wow Batman

 

[Keyboarder]

Enjoying the heck out of my MX4s with the RME-ADI2 DAC this fine evening.

How are the LCD-MX4's directly into the RME ADI-2 and are they sensitive enough that you use the smaller IEM output or the larger regular headphone out?
I just finally gave in and ordered the ADI-2 and wondering if it will be adequate or if I should consider adding a THX 789 or 887 so I can use my balanced MX4 cables.

Info much appreciated!

 

[paulybatz]

Regular or pro RME

 

[Zojokkeli]

How are the LCD-MX4's directly into the RME ADI-2 and are they sensitive enough that you use the smaller IEM output or the larger regular headphone out?
I just finally gave in and ordered the ADI-2 and wondering if it will be adequate or if I should consider adding a THX 789 or 887 so I can use my balanced MX4 cables.

Info much appreciated!

I’ve driven MX4s adequately with a Playstation 4 controller, so literally any DAC/amp will have enough power to drive them.

 

[Keyboarder]

Regular or pro RME

The regular version with updated AKM AK4493 chip

I’ve driven MX4s adequately with a Playstation 4 controller, so literally any DAC/amp will have enough power to drive them.

Yeah, I've used my MX4's with a LGV35 phone and surprised how good it was, but wasn't as good as with a proper desktop amp. I'm not just looking to drive them, but looking to drive them to the peak of their capability, or near it.

I'm really wondering if they are efficient enough to use the IEM interface. I know I can just wait and try it, just wanted to know others thoughts and experiences.

 

[paulybatz]

I’ve driven MX4s adequately with a Playstation 4 controller, so literally any DAC/amp will have enough power to drive them.

Whhhaaaattttt???