[JohnR]

I'm listening here to a different amp than last night. In a pinch, I would pick the one I had last night, and I think I can clearly tell the differences between these amps. I haven't measured them yet (shh...) but I wonder what others have thought when comparing headphone amps. Was it night and day, or very subtle? What was the reason for preferring one amp over another?

[rollo]

  Tonality and harmonic stucture. Character of sound basically. Bright and thin ? Rich and texured ? Does it make me want to dance ?
    Most Amps  however suffer at the extremes, meaning the bass and treble.  Some sublte some night and day.  Hard to generalize. Most  Amps are very close in tonality in the midrange. The treble can be overbearing with some Amps such as being overdetailed and or bright. Bass can be smeared or boomy. Small differences yes. However can make or break the deal.
   
    With any new component in the system an ABA comparison is required. For me it boils down to how it sounds. Differences although small can make or break the decision.
   

charles
     
   

[JohnR]

Charles... you are talking about headphone amps here, right? Just wondering... as there's that dang cord to worry about when dancing.

[saisunil]

Tonality
Soundstage - in or out of head, narrow vs wide
Bass - full, tight or boomy
Listenability - at low and higher volumes
Balance - left to right
Self Noise with no music playing - slowly raise the volume from zero to high
Tactile
If it is a tube gear - it has to be heard with recommended or good tube
Headphone Matching with low z (akg) and high z (Senn) and easy to drive (Grado) vs hard to drive (ortho)

Hope it helps

[hibuckhobby]

If I have to choose between analytical and lush...I prefer lush.
I don't like overbearing bass, but I can tolerate the bass being
a bit forward whereas, a forward upper-midrange/lower treble
will have me making changes quickly.  I have more than one amp
and more than one set of cans because I like listening to all the music
I own rather than just a few very well recorded songs.
Hibuck...

[randytsuch]

It also depends on the cans used.

Some amps do better for low impedance (32 ohm grados), some for high impedance (600 ohm or thereabouts).
And then there are planars, like the LCD-2 and Hifiman HE series.

I tend towards analytical, but if you have analytical cans you can go too far.

Randy

[DaveNote]

My experience with headphone amps has been disappointing, until now.

I had an early Grado battery driven model. The build was disgraceful and it had a terrile hum. I exchanged it for X-Cans. OK, but better than using the headphne jack on my Bryston preamp. I had the same experience with a Creek and the very good Grace Designs m902. All of them even the Grace, had some noise at higher volumes. I really liked the sound of the headphone jack on my Pioneer vintage SX980, but it failed on me twice.

The greatest disappointment for me was the Schiit Lyr. Nice warm sound, but it had a terrible hum played at volumes starting above 9:00 o'clock. I couldn't get over the feeling that the hum was affecting its performance at lower volumes. I sent it back to Schiit and they could find no hum. But I don't have a ground loop, as was suspected. I tried various tubes and some worked better than others, but the hum never disappeared.

The O2, a recent acquisition is, as I've said elsewhere on this circle, completely noiseless on my system, proving of course that I don't have a ground loop. The absence of any noise or distortion was the night and day experience for me. I like it a great deal because of its transparency, not because it has some kind of sound of its own, as was the case with the Lyr even when I cold overlook its hum.

Dave

[Sparky14]

About all I can tell is background noise.

Soundstage / dynamics / warm fuzzy feelings.... I cannot tell much difference between amps.

[JohnR]

Thanks for the responses guys. I'm with you on the noise, I was listening to a highly rated amp that had a terrible power supply and until I replaced it (the power supply) it was pretty hard to stomach.

There seem to be so many things to consider. For example, one thing I don't like about the O2 is the way it behaves when the battery goes flat. So I'm inclined to leave it connected to the transformer all the time.

Tonight I'm listening to a not-a-headphone-amp. That is, an audio interface I bought for speaker/room measurement. All of these things have headphones outputs on them. I really quite like this one, unlike my previous unit.

[irishsammy]

I've got a $1000 Woo amp (WA6-SE) and a $200 Maverick Audio amp (A1) and honestly, the differences between the two of them are more related to source and headphones used than to the amps themselves.  So personally, I feel that amps are primarily a means to an end.

But having said that, there's no way I'd plug my LCD-2's into the Maverick (not near enough power) and my 600 ohm DT880's sound quite a bit lusher and relaxed with the Maverick vs. quite a bit leaner and crisper with the Woo. 

I think it takes a good bit of work to match up all 3 aspects of the chain to get a sound that you like out of a given set of cans.  In that sense, the amp absolutely makes a difference.

And keeping with the perceived subtheme of this thread, the only noise I've ever heard out of either of my amps is with IEMs.  They're both dead quiet with full-size cans.   

[adydula]

I look for an amp that is totally transparent and adds nothing to the picture except enough power to make my headphones reach their
limits.

Its the old straight wire with gain philosophy.

All the other stuff like cosmetics, batteries, shape, size are secondary....but would influence me to look at if they had the same specs
that would make me believe that they were indeed 'transparent'..

Alex
 

[DaveNote]

Thanks for the responses guys. I'm with you on the noise, I was listening to a highly rated amp that had a terrible power supply and until I replaced it (the power supply) it was pretty hard to stomach.

There seem to be so many things to consider. For example, one thing I don't like about the O2 is the way it behaves when the battery goes flat. So I'm inclined to leave it connected to the transformer all the time.

If I have any complaint about the O2 it is about the battery thing. For now it's not a problem because I use both of mine strictly with the transformer plugged in 24/7. But I'm concerned about what to do when the batteries go bad. Not being at all technical and all thumbs, I'm not looking forward to taking them out. So I'm planning on buying the Desktop version on the O2, and I'm hoping it will be available sooner rather than later.

Dave

[eclein]

The very first headphone amp I tried was a littlle Fio and the difference between that and coming str8 out of an ipod touch was subtle at first but became clearer over time
either because of my ears or break-in. I seem to hear more defined differences in the portables than the larger ones. I use an Asgard for my HE-5LE's and I get wonderful sound
and at 1/2 volume on the Asgard and a nudge up on the pre gets it louder than I'll ever listen to. I love it and saved a bundle by not going nuts on a super stoutly
powerful one.
  I used them with an MP301MK2 which had 6Watts x 2 in the headphone section and the sound wasn't that much better if at all with the excess power. Thats probably an unusual case
I think, but I go all in for tonality myself!

[adydula]

Dave,

take out the four screws in the front panel of the O2 and gently slide the amp pc board out...you can then remove the batteries if
you like.

Then slide it back in the same slot it came out of.

There is a small piece of wire that is soldered to the input jack that wraps around the bottom right screw for a case ground...
Just make sure it goes around that screw...you will see where JDS has filed away the coating to get to the
bare aluminum case for good ground contact..

Simple!
 

Alex

[DaveNote]

Dave,

take out the four screws in the front panel of the O2 and gently slide the amp pc board out...you can then remove the batteries if
you like.

Then slide it back in the same slot it came out of.

There is a small piece of wire that is soldered to the input jack that wraps around the bottom right screw for a case ground...
Just make sure it goes around that screw...you will see where JDS has filed away the coating to get to the
bare aluminum case for good ground contact..

Simple!
 

Alex

Thanks for the instructions, Alex. They are helpful. Unfortunately, when I said I knew nothing about technical stuff and am all thumbs, I wasn't exaggerating.

Years ago, we had a loss of power in an old home we had. I looked at the panel and couldn't make out what I was seeing, and ended up calling an electrician. He calmly replaced a blown fuse I couldn't see and kindly didn't even make fun of me. He was smiling too broadly, I think, taking my money! 

So even if or when I follow your excellent instructions, there is a pretty good change I'll screw up something. As I undersand it, the batteries in these units last for a couple of years; not sure if that applies to units using the transformer 24/7. Anyway, in that time I might end up ducking the whole problem. If not by getting hit by a bus, perhaps by electrocuting myself changing a light bulb. 

Dave

[adydula]

Dave if you were next door I would take all your stuff apart!!!

 

Alex

[DaveNote]

Dave if you were next door I would take all your stuff apart!!!

 

Alex

Alex, spoken like a friend. Much appreciated. But take care. Grouch Marx had a great line when he said, "I wouldn't want to be in a club that would have me as a member." I'm not sure I would want to live in a neighbourhood that would want me as a neighbour. 

Dave