[viralcow]

I'm confused. Are you saying it's too loud? Don't have your amp so I don't know.

 

[elwappo99]

 

  Very first comments: I have to set the volume around -5 or even 0 dB in order to hear the music at the level I like.
Is this normal?

guys, help!
I need to understand if:
A) my headphones are faulty
B) there is a problem of impedance between headphone amp and headphones themselves 
C9 how can I solve this?
Thanks

 
Unfortunately I can't find a lot of information on the power output of that unit. Are you totally maxing out the volume, or are you just worried that you've turned the volume too high? What is your Audiolab unit hooked up to?
 
The K601 was a surprisingly power hungry amplifier, so I'm not surprised you need to push the volume. 

 

[doraymon]

The problem is that I have to push the volume of my amplifier almost at full scale (between -5 and 0 db) in order to make the headphones play "loud enough".
I am hooking the cans to my Audiolab 8200DQ, which is a preamp/DAC with a class A headphone amp.

I suspect it might be an impedance issue but I am waiting to know from Audiolab which is the exact output impedance of the headphone section.

I am quite surprised though as I read many reviews about the 8200DQ stating that it has a good headphone amp, and I also never read any complains about the K612 being so tough to drive...

 

[elwappo99]

The problem is that I have to push the volume of my amplifier almost at full scale (between -5 and 0 db) in order to make the headphones play "loud enough".
I am hooking the cans to my Audiolab 8200DQ, which is a preamp/DAC with a class A headphone amp.

I suspect it might be an impedance issue but I am waiting to know from Audiolab which is the exact output impedance of the headphone section.

I am quite surprised though as I read many reviews about the 8200DQ stating that it has a good headphone amp, and I also never read any complains about the K612 being so tough to drive...

 
It certainly could be the 8200DQ doesn't have quite enough power for the K612. I think the K612 is so new there aren't a lot of impressions, but the K601 and K501 I had both really required a lot of power. I think the Audio-gd ROC almost required me to max out the volume to get them to a good listening level. 
 
Unfortunately, I couldn't find any solid documentation on the 8200DQ's output impedance or output power. I will say it looks like a very aesthetically pleasing unit. Hope it looks that good on your rack! 
 
 
Edit: Seriously, smooth, sleek, modern
 

 

[doraymon]

Yeah! It looks fantastic, and more important it sounds even better with its brother power amp and my CM9 speakers. I'm really enjoying it! But couriously enough my neighbors do not appreciate! For which reason I need the headphones...

 

[Andreas_D]

Hi guys,
 
I would like to give k612 a try, after I had k601 a while ago and really liked them, even without a decent dac/amp. How I'm planning to buy an usb dac/amp combo in 300$ price range.
 
Until now I've looked at Audioquest Dragonfly, the new Fiio E18 and EHP-O2D from Epiphany Acoustics, practically a ODAC + O2. I'm open for other combos recommandations, but I have to mention that I don't like harsh, sibilant or dry sound.
 
What can you suggest me to buy for k612? Which combo that you've heard has the best sinergy in your opinion?
 
Thank you in advance!

 

[kman1211]

  Hi guys,
 
I would like to give k612 a try, after I had k601 a while ago and really liked them, even without a decent dac/amp. How I'm planning to buy an usb dac/amp combo in 300$ price range.
 
Until now I've looked at Audioquest Dragonfly, the new Fiio E18 and EHP-O2D from Epiphany Acoustics, practically a ODAC + O2.
I mention that I don't like harsh, sibilant or dry sound.
 
What can you suggest me to buy for k612? Which combo has the best sinergy in your opinion?
 
Thank you in advance!

I haven't heard that good of things about the O2 with the K612, it seems it's a bit dry on that set up. I personally think the Hifiman EF2A with Mullard tubes is a great combo but the dac on the EF2A isn't that good sadly. I haven't heard anything about them on the others you listed.

 

[doraymon]

Unfortunately, I couldn't find any solid documentation on the 8200DQ's output impedance or output power.

I sent an email to the manufacturer to get the output impedance of the headphone amp installed on the 8200DQ.
I will post the answer so you can help me judge if mine is an impedance problem and I really need an additional headphone amp... (Hope not)

 

[Punnisher]

I sent an email to the manufacturer to get the output impedance of the headphone amp installed on the 8200DQ.
I will post the answer so you can help me judge if mine is an impedance problem and I really need an additional headphone amp... (Hope not)

It's hard to imagine any piece of gear not being able to drive headphones with enough volume. Even my sansa clip, and all of my other daps and portable amps would drive any headphone I own to painful levels of volume (not necessarily sounding good, but loud). It's most likely a headphone cabling issue, configuration issue, or defect in your preamp.
 
First, try another pair of headphones on your preamp and see if it has the same problem.
 
Next, try your 612 on another piece of gear (receiver, mp3 player, computer, friends amp/preamp/receiver, etc). Anything with a headphone jack should be able to produce sound.
 
Is there a "mute"  setting or switch that could be causing this issue? Look in your manual about a possible solution.
 
If none of these help, I'd call the manufacturer and see about a diagnosis at a local warranty repair shop.
 
On another note, it sounds like you've got a great setup. My friend has a system with Esoteric dac, Rotel preamp and CM8 speakers. I got the bug as well and have a Rotel preamp and 685 speakers. Love them.

 

[doraymon]

  It's hard to imagine any piece of gear not being able to drive headphones with enough volume. Even my sansa clip, and all of my other daps and portable amps would drive any headphone I own to painful levels of volume (not necessarily sounding good, but loud). It's most likely a headphone cabling issue, configuration issue, or defect in your preamp.
 
First, try another pair of headphones on your preamp and see if it has the same problem.
 
Next, try your 612 on another piece of gear (receiver, mp3 player, computer, friends amp/preamp/receiver, etc). Anything with a headphone jack should be able to produce sound.
 
Is there a "mute"  setting or switch that could be causing this issue? Look in your manual about a possible solution.
 
If none of these help, I'd call the manufacturer and see about a diagnosis at a local warranty repair shop.
 
On another note, it sounds like you've got a great setup. My friend has a system with Esoteric dac, Rotel preamp and CM8 speakers. I got the bug as well and have a Rotel preamp and 685 speakers. Love them.

It's not that there is no sound, as I said I am wondering if it's normal that I have to push volume to almost full scale to get them go loud.
 
On another note, thanks for your comments on my setup. 685s are great speakers, I heard them more than once! And I was also hesitating between a Rotel integrated stereo amp and my actual setup. So it looks like we have similar tastes...

 

[doraymon]

Ok guys, finally I received the specs of the headphone output of my Audiolab 8200DQ:
 
8200DQ’s Headphone output:
- output impedance：7.5 ohm
- MAX output : 5.8Vrms/100R
 
Now the question is, with this specs, and having the headphones an impedance of 120 Ohm, can this be the reason why I have to turn the volume knob to almost full scale to make them sound loud? 
 
Please help.
 
EDIT: I just found out that the serial number on the headphones is different from the one on the box. The box came perfectly sealed and the headphones looked perfectly wrapped. What is this????????

 

[manbear]

  Ok guys, finally I received the specs of the headphone output of my Audiolab 8200DQ:
 
8200DQ’s Headphone output:
- output impedance：7.5 ohm
- MAX output : 5.8Vrms/100R
 
Now the question is, with this specs, and having the headphones an impedance of 120 Ohm, can this be the reason why I have to turn the volume knob to almost full scale to make them sound loud? 
 
Please help.
 
EDIT: I just found out that the serial number on the headphones is different from the one on the box. The box came perfectly sealed and the headphones looked perfectly wrapped. What is this????????

The AKG website says that the K612 has a sensitivity of 101 dB/V. Implying that you would only need 1 V to get 101 dB. Considering that you should have about 5.8 V from your headphone jack, you should be able to get painfully loud on the K612. So something must be wrong somewhere. 

Check the settings of your preamp. Maybe there is some kind digital volume, EQ, or other sound processing setting that's affecting your max volume. Also check to see if you have gain settings. If so, increase the gain. 

Try the AKGs on a different headphone jack, like on your computer. If they get really loud, the problem most likely lies with the preamp. If they don't get really loud, the problem most likely lies with the headphones. 

 

[doraymon]

 
The AKG website says that the K612 has a sensitivity of 101 dB/V. Implying that you would only need 1 V to get 101 dB. Considering that you should have about 5.8 V from your headphone jack, you should be able to get painfully loud on the K612. So something must be wrong somewhere. 

 
Isn't this true only if the 5.8 V max output of the amplifier are measured at the same impedance of the headphones?
Obviously it is not clear at which impedance is this max output measured.
They wrote: MAX output : 5.8Vrms/100R
Maybe that "R" is not an R but an omega (Ohm)?
 
I think I will buy a decent headphone amp online, try it and if it doesn't solve the problem I will send it back...
 
Any suggestions on something (within 150/200 Euro) which is known to work well with the K612?

 

[manbear]

I assumed that "100R" meant 100 ohms, in which case it is close enough to your headphone impedance of 120 ohms that it shouldn't make much practical difference. But you are right that the voltage output of the amplifier varies with respect to headphone impedance.

 

[doraymon]

Guys while waiting to receive a test headphone amp, I stop worrying about specs, I put some good music and I am enjoying it! Maybe not as loud as I wanted, but these cans are amazing...
Just to share the experience I post a picture with all the "family" at work.