[Syrk]

Hi, I've been lurking these forums for the past month figuring out what to get as my first set up. Last week I finally decided to get the audio-gd nfb-12 and a pair of dt 880 600 ohm headphones. I just started listening to this set up and I noticed when I have the volume knob past 1 o' clock I start noticing distortion (if that's the right word). When I put in my a700, it can go up to max volume with no distortion. Is it because the nfb-12 is not giving it enough power or is there something wrong with my cans? Thanks for any input.

 

[TheWuss]

Syrk,
Usually it is not as simple as "is it my cans or the amp?"
We need to know some other things.
The audio gd unit is a dac and amp. So, what music player are you using? Do you have any dsp or equalization functions on?
I have found that some headphones will show up problems with your source material or mp3 player, while others do not.
So, it may not mean that your beyers are broken....

 

[Syrk]

I'm listening to flac on winamp. I never messed with any settings/functions since installing winamp on my computer.

 

[TheWuss]

Well. The first troubleshooting path would be to download foobar2000 player and play files through one of its bit perfect ouput methods.
And the second one would be to play the dt880 through other sources and amps to see if you can recreate the distortion. Do you have a home theatre receiver? Anything else to try the cans on?

 

[HiFlight]

My DT880's (600 ohm) also seem to be a bit more susceptable to high volume distortion than most of my other cans.   It happens at a level higher than I normally listen so is not a problem, but for some who listen at quite high volume settings, it might be of more concern.  
 
It would be my guess that at the 12-1:00 position of your volume control, you would be listening at quite a high level.
 
 

 

[Adda]

My 600 Ohm K240DF's start sounding sharp if played loud out of an amp that doesn't drive them well (like an LD mkV).
If you have access to a (preferably vintage) receiver or integrated amp with a headphone output, try it out and see if things change, if they do, your NFB-12 doesn't have what it takes.
600 Ohm headphones need voltage and more voltage, most headphone amps amplify current and won't work well with such high impedance cans.

 

[Syrk]

@TheWuss @Adda I tried it on my receiver (denon avr-391) and I noticed the same distortion when I put it at a high volume level. I don't have access to anything else. As for using bit perfect output on foobar2000 I'll have to figure that out.
 
@HiFlight Thanks, that gives me some relief that my cans aren't bad. I really shouldn't be putting my volume past 12 anyways. It does sound fine with no noticeable distortion below 1:00. I wouldn't want to return these cans considering I got them at $158 open box new.
 
Also, will burning in these cans help the situation? and is distortion normal on cans that aren't being driven properly (at higher volume levels)?

 

[Adda]

I would not trust that Dennon with headphones, it's too modern, I'm quite sure it doesn't drive headphones with it's power amp, I could be wrong, but someone would have to check to convince me.
Also it's quite modern so 600 Ohm headphones where not on the mind of the people who designed it.
All in all that Dennon is most likely not a good amp for 600 Ohm headphones either, something form the late 70's early 80's will trounce it (Nikko, Sansui, Pioneer, Kenwood, Yamaha, Luxman, Harman/Kardon, Marantz, Sony, Hitachi)
 
Burn in might help, but I doubt they will change much beyond a weeks time of heavy use.

 

[tim3320070]

The NFB12 puts out 0.15 watts at 600ohms, whereas the Phoenix puts out 0.9 watts. It might be pushing the limit of the 12's capabilities. I don't hear this distortion with my DT770/600 before it hurts my ears. Then again, the 600ohm Beyers are tough to drive for sure. Make sure all the settings in Winamp are off such as EQ and that the volume is at max.

 

[HaVoC-28]

http://europe.beyerdynamic.com/shop/media//datenblaetter/A1_DB_E.pdf
 
Beyer Dynamic A1 only output 100mw at 600ohms , and i don't think  that they have any problem feading Beyers 600 ohms . 
 
 
 

 

[Zombie_X]

OP, the distortion you are hearing is clipping. Your amp sadly can not output enough power for the headphones and is running low on power reserves. That's when clipping comes in.  My X-CANV8P can drive my 600Ohm beyers nicely but will clip if you drive them too loud. If you want todrive them properly you might have to upgrade to a different amp or downgrade your headphones.
 
I find that the NFB-10SE (nearly same as my ROC) has more than enough juice to drive the beyers. Plus it's only $499 on sale on Audio-GD.com.It outputs 590mw into 600Ohm which is plenty enough IMO. 
 
Another option is the SPL Auditor (big fan I might add 

) and it can output 1.7W into 600Ohms 

. I have tried it on several 600Ohm headphones and it drives all the beyers, K240's, random vintage headphones with ease. The only downside is the hefty price you pay for that power.
 
I would not recommend the A1 amp though. I know beyer made it for the 600Ohm headphones but IMO the amp isn't worth it. From what I understand out output impedance on headphone amp the A1's is just too high at 100Ohm's. When I had heard the A1 it seemed to muddy beyers signature bass. It did give them more weight and body but at the cost of some tightness and texture. Also the higher impedance skewed the frequencies to make the highs a bit more relaxed. I just didn't like ti at all.
 
Not saying you have to upgrade, but just letting you know some options.

 

[Achlys]

I know this thread is old, but it's the first one to show up on google if you search for "DT880 600 Ohm distortion." It has nothing to do with driving them properly. The headphones simply have a ton of bass distortion.