[negura]

   
or just use tape and cover the edge where the housing leaves a gap as @Armaegis said. Using tap, I too experience tighter bass, liking the change in SQ tape will remain. 

 
 

Sealing the driver to the housing. Didn't think it would make much of a difference either.

 
Ok you guys got my interest. I will try with tape first since it's in stock. =) I need to unscrew the 4 screws and remove the plastic ring on top of the driver first, I reckon.

 

[ohhgourami]

Ok you guys got my interest. I will try with tape first since it's in stock. =) I need to unscrew the 4 screws and remove the plastic ring on top of the driver first, I reckon.

Don't need to remove the ring.

 

[bitsnbytes]

Careful with taping... If you take off the tape the electroplated black piano paint might come off with the tape

 

[Silent One]

HE-6 might have the tightest bass of any headphone now with the seal from Blutack.

Yum-o! 

 

   
Well, the quickest and easiest way is to put an appropriately rated 10ohm resistor directly across each of the L/R  8 ohm speaker terminals - with the headphone cable connected directly as well.
This eliminates all the connections/joins/extra cable required with the adapter box.
The series resistor - which is used as a fuse in the adapter box - is really not a requirement if you're judicious with the volume control. But only you can make that call.
 
I think most people using solid state amps are just connecting directly and using their good judgement (most SS amps won't require the load matching parallel resistor).

I remember a couple of members doing that here and posting a pix (10 Ohm resistor). Will def try that! Though, I always connect cans at zero volume and slowly raise it once I get going, is your concern with volume simply at higher listening levels something bad might happen? To my precious lovelies or the HE-6??

 

[Tobes]

  Yum-o! 

 
I remember a couple of members doing that here and posting a pix (10 Ohm resistor). Will def try that! Though, I always connect cans at zero volume and slowly raise it once I get going, is your concern with volume simply at higher listening levels something bad might happen? To my precious lovelies or the HE-6??

 
The concern is only misuse due to the potential power available from a speaker amp.
If you connect/use the amp as you say, then there should be no problem. I'd say it would be impossible to overdrive the headphones while actually listening - since the SPL would be unbearable.
 
Obviously, as with the adapter box, the parallel resistor should always be connected when the amp is in use (this is to terminate the amp correctly - it offers no protection to the headphone).
Remember, if your headphones are 50ohms, then 4/5 of the output power generated will go into the parallel 10ohm resistor so it should be rated accordingly.
Mundorf make some (supposedly) very good power resistors with very low inductance, designed specifically for audio use.
The 20W power rating on the resistor linked below would be overkill for this purpose - though of course its would still be possible to overdrive the resistor to failure by cranking up the power amp. It would appear the parallel resistor in the adapter box is much lower rated and has proved sufficient.
 
http://www.hificollective.co.uk/components/mresist.html

 

[Kununa]

I have a question. I read that the Audio-GD NFB 10.32 should drive the HE 6 properly and as it can output 6W into 50R it should, in theory. But when I turn it up to max volume in high gain it can bring the HE6 to normal listening levels but not loud. I also have the EF6 which can drive my HE6 pefectly. Anyone know why is that?

 

[preproman]

Check to see what the gain is on both.  Report back..

 

[DreamKing]

  I have a question. I read that the Audio-GD NFB 10.32 should drive the HE 6 properly and as it can output 6W into 50R it should, in theory. But when I turn it up to max volume in high gain it can bring the HE6 to normal listening levels but not loud. I also have the EF6 which can drive my HE6 pefectly. Anyone know why is that?

 
It's because you have to be in balanced mode to get the higher output levels. That's the way their balanced amp/dac hybrids work. The Master 9, for example, is more versatile. With the others you have to make a choice between balanced or single-ended for more output power or all-around better performance.
 
I'm saying this assuming you aren't running balanced, so just want to make sure.

 

[Kununa]

What does running balanced mean? I'm using the balanced output.

 

[DreamKing]

What does running balanced mean? I'm using the balanced output.

 
Strange...It should give you loud volume technically. Contact a-gd I suppose, sorry that's all I got.

 

[NZtechfreak]

  I have a question. I read that the Audio-GD NFB 10.32 should drive the HE 6 properly and as it can output 6W into 50R it should, in theory. But when I turn it up to max volume in high gain it can bring the HE6 to normal listening levels but not loud. I also have the EF6 which can drive my HE6 pefectly. Anyone know why is that?

 
Don't know, but my experience with the Reference 10.32 with the same output power intp 50ohm was fairly similar. At the highest levels on high gain it could get moderately loud on loudly mastered albums, but still suffered with the usual signs of an under-driven HE-6 (somewhat collapsed/congested soundstage, less accurate imaging, slighty boomy bass).

 

[wuwhere]

Could be current limited? The HE-6 is also inefficient.

 

[DreamKing]

By Ohm's law, the current is enough to output 6W if that's what they specify it outputs at 50 ohm. Efficiency is power based. 

 

[wuwhere]

Perhaps that amp is over-rated for the power at that load. They didn't even specify the frequency range and distortion.

 

[headwhacker]

high output impedance will also reduce the amount of power delivered to the headphone.