[remilio]

Originally Posted by Ergoforce /img/forum/go_quote.gif
 
So it is by design that low impedance headphones (even as high as 100 Ohm), will generate hum noise on M9 if connected single end.
 
I wonder if the hum noise also would be present for Sennheihser HD700 with impedance of 150 ohm. My guess is it would be audible.

 
I cannot confirm that. I tried many low impedance phones through single-ended output of M9 and none of them had hum. UNTIL the certain level of volume (which is BTW insanely loud).

 

[Articnoise]

 

I got an answer back from Kingwa. I quote:
 
"Audio-gd headamp product models had high power output and high gain, they are not suited in ear headphones.
Kingwa"
 
A disappointing answer. During the years, I have tried around 10-15 different high-end headphone amplifiers. None of them had problems with hum noise using ER-4*.
 
So it is by design that low impedance headphones (even as high as 100 Ohm), will generate hum noise on M9 if connected single end.
 
I wonder if the hum noise also would be present for Sennheihser HD700 with impedance of 150 ohm. My guess is it would be audible.

 

No noise and no hum with any headphones or in-ear I have tried with the M9. Maybe worth to try without the HE-350 and see if it will help. 

 

 

 

[Ergoforce]

Already did. 

   

No noise and no hum with any headphones or in-ear I have tried with the M9. Maybe worth to try without the HE-350 and see if it will help. 

 

 

 
Already did. Either someone else will confirm this trying M9 + Etymotic ER-4*, or my M9 is not functioning correctly.
 
Knowing the impedances of the in-ear and headphones you've tried, would help me to suspect it's my M9 is wrong. I see several of starved solder joints inside M9. Or Maybe chassi- and signal grounds are swapped on the single end jack or connected where it shouldn't be.

 

[Ergoforce]

   
I cannot confirm that. I tried many low impedance phones through single-ended output of M9 and none of them had hum. UNTIL the certain level of volume (which is BTW insanely loud).

 
The question is how low were the impedance(s) on the headphone(s) you tried?
 
ER-4PT is 27 Ohm, ER-4S and ER4SR are 100 ohm. The hum is louder with ER-4PT and as I wrote earlier, I shorted all inputs on M9 and the hum noise is constant regardless volume level ( = even level 00).
 
And I assume you haven't tried with Etymotic ER-4* headphones?

 

[remilio]

   
The question is how low were the impedance(s) on the headphone(s) you tried?
 
ER-4PT is 27 Ohm, ER-4S and ER4SR are 100 ohm. The hum is louder with ER-4PT and as I wrote earlier, I shorted all inputs on M9 and the hum noise is constant regardless volume level ( = even level 00).
 
And I assume you haven't tried with Etymotic ER-4* headphones?

Reread your previous post, you talked about <100Ohm headphones in general. I haven't tried Etymotics, using IEMs with such a monster is not my cup of tea.

 

[Articnoise]

  Already did. 
 
Already did. Either someone else will confirm this trying M9 + Etymotic ER-4*, or my M9 is not functioning correctly.
 
Knowing the impedances of the in-ear and headphones you've tried, would help me to suspect it's my M9 is wrong. I see several of starved solder joints inside M9. Or Maybe chassi- and signal grounds are swapped on the single end jack or connected where it shouldn't be.

 

I don’t normally use in-ear with the M9, but sometimes I use it to test the noise floor in gear. I have also used in-ear occasionally to watch Netflix series.  I have for example used Klipsch s4 which are 18 Ohms and couldn’t detect any hum at all. I’m not an tech but I really don’t think that lower impedance will make you hear more hum per se. Low impedance and high sensitivity will make you hear noise that you normally can’t hear with over ear HP. You have said that the problem is only with one type of in-ears. Maybe they have so high sensitivity that they can revile hum not normally detectable with other cans.

 

Some horn speaker that have very high sensitivity can be very hard to find a good amp for because they will show you the smallest/lowest of noise.

 

Hum is often a main power think. Some gear are clearly more sensitive to the quality of the mains power and the mains power are in turn affected by all the gear on the entire grid, but most by the ones in the same building. The hum noise can be mechanical caused by the transformers that start to vibrate at 50/60 Hz. Normally this hum noise comes from the gear itself and not thru the audio signal to your headphones. With ground-loop hum you can mostly hear the hum coming from your headphones.

 

I’m, ones again, no expert but I don’t think that the shorting of ground is sufficient to eliminate if it’s a ground-loop hum or not. The thing that causing the hum can be backwashed thru the mains power in to the DAC or amp. I think you need to turn everything else off (if you haven’t already done this), including the HE 350. Then tracking down the hum problems by the process of elimination one gear at the time. The thing that is causing hum don’t have to be the one that will let you hear it.

 

If the problem really is the M9 and it can very well be, you will then know and can take actions - sell the M9 or don’t use the specific in-ear or.... I don't know

 

Good luck!. 

 

[dan.gheorghe]

You just don't buy M9 for in ears... if that is the main purpose, stay away from Master 9. You can also find something considerably cheaper, like Aune B1, which I found to be just wonderful. It is actually the best portable amplifier I have heard.
 
B1 isn't the best choice, however with very very efficient in ears, but it's amazing with portable headphones that require a reasonable amount of power.

 

[Joeybgood]

  You just don't buy M9 for in ears... It's that is the main purpose, stay away from Master 9. You can also find something considerably cheaper, like Aune B1, which I found to be just wonderful. It is actually the best portable amplifier I have heard.
 
B1 isn't the best choice, however with very very efficient in ears, but it's amazing with portable headphones that require a reasonable amount of power.

Question for any US HeadFier. Approx how long dig it take your Master 9 to arrive on your doorstep from the time AGD ships?

 

[kevin gilmore]

it was either 3 days, or 4 days, don't remember anymore but quick.  It was shipped DHL

 

[Joeybgood]

  it was either 3 days, or 4 days, don't remember anymore but quick.  It was shipped DHL

Wow... was not expecting it to arrive THAT quickly! It IS coming FROM China.. yes?

 

[Samut89]

it was either 3 days, or 4 days, don't remember anymore but quick.  It was shipped DHL

Hi bro,
It is an honour to meet you..
Hoping to ask your opinion on something if you are willing to answer..

The questions is:
How would you compare the schitt ragnarok vs the master 9 vs the Xindak pa(m) II..?

I am curious to get the raganarok as i think the master 9 is bottleneck my schitt yggy..

Greatly appreciated,
Jonathan

 

[jjacq]

Hi bro,
It is an honour to meet you..
Hoping to ask your opinion on something if you are willing to answer..

The questions is:
How would you compare the schitt ragnarok vs the master 9 vs the Xindak pa(m) II..?

I am curious to get the raganarok as i think the master 9 is bottleneck my schitt yggy..

Greatly appreciated,
Jonathan

 
My 2c.... I owned the Mjolnir 2 and tested the Ragnarok before I decided on the Master9. I like the M9 more than the Rag because it just had more microdetail and control altogether. The Rag is a bit bright on the treble region just like the Mjolnir 2 so I'm guessing it's a Schiit amp thing. I also heard this from the Valhalla 2. I don't really think the Master9 will bottleneck the Yggy at all, if anything the Rag will. 

 

[dan.gheorghe]

Hi bro,
It is an honour to meet you..
Hoping to ask your opinion on something if you are willing to answer..

The questions is:
How would you compare the schitt ragnarok vs the master 9 vs the Xindak pa(m) II..?

I am curious to get the raganarok as i think the master 9 is bottleneck my schitt yggy..

Greatly appreciated,
Jonathan

That xindak seems to have the same specs as the bigger one I have owned, the xindak A600E 09 version. I have tested a600e vs Master 10 and Master 10 was cleaner, more detailed and had better dynamic range. Xindak also had some nice features like soundstage, impact, viscerality. 
 
https://headmania.org/2015/08/17/xindak-a600e-09-version-integrated-speaker-amplifier-review/
 
I have tested LCD-4 from Master 10 directly. Well...Master 9 was superior in the details and clarity department. I would say that M9 would be more detailed, more transparent, will have better dynamic range than the xindak pam, but the latter has some chance to have a bigger soundstage and sound more energetic. 

 

[Youth]

Anyone compared M9 and HE-9?

 

[fradoca]

i have the master 9.i use it with my lcd-x for audio mastering and critical listening sessions.
in a month i should receive a brand new HE-9 so i'll be able to make a comparison.