Axiom Home Page Forums General Discussion Advice from Axiom Owners Is it worth getting a headphone amp

I have to admit that, when I first looked into this (12 months ago, after I received my HD650 and found them clearer, but a bit flat compared to my previous ones), I was disappointed with head-fi.org. For each comment that seemed to be leading somewhere, I found 2-3 that dealt with (for example) replacing the interconnect cable with some different aliage and getting phenomenal result or things like that.

I actually dropped the whole thing a few months later, discouraged that I would ever find something meaningful (short of buying a 1000$ device to try it!). Then I bought a pair of Sennheiser PXC-250 for my iPod and the device could not drive them (no dynamics at all with the volume at 100%). Since I did not want at that point to invest a lot of money on something I was less than convinced about (I was more convinced before I went to head-fi.org!), I bought the tiny boosteroos amp at 40$ (it was on special). QUITE an improvement. Really impressive.

Now I am waiting for 2 solid-state "Little Dots" (one borrowed for iPod, one bought (with exit stategy if I don't want it) for receiver). I am still far from convinced for the receiver, but I would really like to get the same dynamics I had with my cheaper headphones (the HD650 are otherwise marvellous).

I had a point before I started rambling (): head-fi.org is probably filled with a lot of well-intentioned people, but I have to admit it is also filled with very spectacular assertions that I would like to see backed up by some proper experiments.

Alan, do you feel that this distortion in tube amps ONLY colors the sound? What about the increase in clarity, soundstage, bass tightness, realism, separation of instruments, and many other sound improvements that many listeners report to hear. These don't seem to be just attributed to 'distortion' can it? Also, I don't think they change the sound in the original recording, but rather they bring the sound closer to the original recording as it was meant to be heard.

While I do have my doubts about certain drastic improvements one can get with hi-fi equipment, there are too many anecdotal accounts from many listeners, and even my personal experience can attest that what I hear when I listen with a headphone tube amp is not just coloring, but improvement in "sound quality". I will admit there is warming of the sound, possibly this is the distortion as you say, but I can't deny the greater satisfaction of musical enjoyment. Subjective yes and even if it is measured as distortion...

Alan, you make excellent points, as usual.

But I feel that I must point out that not everyone believes that the enjoyment of music is based entirely on the objective specifications of the equipment. I know, a lot of people around here say it is, and it's one of Axion's core beliefs. But I respectfully disagree. There's no scientific basis why you may like one painting and I might hate it. Likewise with food. I can't stand celery and I don't know why. Same with cars, or beverages, or brands of pencil, or, well, everything. Music is the same way. Everyone's ears are slightly different. But more importantly, everyone's brain is different in terms of how it processes "sound" into "music". Alan, your latest article touches on this. I've read that book you mention, This is your Brain on Music. It's an excellent read that discusses this at length.

And unless you have a live band playing the music for you via unamplified equipment, there is *always* going to be some amount of modification done to the sound waves. I also don't think that recording engineers always have the best interest of the music in mind. See all the recent discussions about the lack of dynamic range in CD's.

But of course, the reality is that Axiom makes speakers and their spiel is neutrality. It's a big reason why I love them. Since they are neutral, they do get out of the way. If I want to throw a tube pre-amp in the line somewhere to 'warm' things up, so be it. Or, heaven forbid, play with a 'Bass' or 'Treble' knob. But the point is that we're not stuck with overly 'warm' or 'cold' speakers for everything.

Here's what I know....
I have a few CD's by a certain acoustic guitarist that I really like. He's a little-known guy. I've heard him live at a couple of coffee-house performances. Very intimate, very live settings. When I don my HD-650's + tube amp, his CD's come alive for me. The music feels like I am back at that live performance. The vibrato on the strings, the soft thump of his hand on the guitar, the sound of his guitar strings rubbing against the bridge, all just "oozes" reality. He's *there*, in my head. Some songs nearly bring me to tears, they sound so good. I can crank up the same performances at home. I often do. It sounds fantastic. There's a spaciousness and depth to it that the headphones simply can't match. But at the same time, it doesn't quite have the same intimacy. Maybe it's poorly mastered CD's that the tubes of my Little Dot are somehow compensating for. Maybe it's the fact that I'm wearing headphones. Maybe I'm just weird. I don't know. But the performance through these tubes are pleasing and simply makes me happy.

Had I listened to and obeyed the 'tubes suck' crowd around here, I never would have experienced that. Which is why I encourage people to trust their own ears, buy from places with good return polices, and to always enjoy the music, even if it takes a tube amp and an equalizer to make you happy.

You make some great points, Peter. When it comes to music, perception is king. If one way of listening to music causes you to have a greater emotional connection to your music than listening in a different way, then perhaps trying to (over)analyze why that is will detract from the experience of music. Naturally, some of that difference has to do with the actual soundwaves being reproduced, but the rest of the contributing factors come from other sources. It would be very difficult to isolate those from each other.

@ EFalardeau - thanks for the detailed info on the booster.

@ alan - thanks for the post. I was and still am very skeptical about dedicated headphone amps which was why I started this thread, hoping to learn more. I never thought about getting one at first because the guy I bought the headphones from asked me what I was using them with, and when I told him a Denon AVR he said that would work fine. He only suggested that I might need an amp for them if I planed to use the headphones with something like a mp3 player or laptop.

Also, what I’ve read here and elsewhere I was concluding that the characteristics people were attributing to dedicated headphone amps was actually because they were tube amps.

@ Peter - excellent post. I did buy my Axiom speakers because I wanted my starting point to be something that was neutral and didn’t colour the sound. Starting with this neutral presentation of what the sound engineer intended I always had every intention and from day one have tweaked it to my taste starting with the volume of various channels.

I’ve always liked the “tube” sound, which sure wasn’t retro when I was growing up, for certain types of music. I listen to lots of ambient, aery, minimalist music and have always felt there is something missing when listening to this on all digital equipment. So even if what’s missing is the tube distortion I want it back. And because I have neutral speakers and integrated electronics I can always have neutral for where I prefer that.

I’ll probably end up getting a tube preamp or amp that I can integrate into the rest of my system.

Does anyone know if there are any digital amps/receivers that have a simulated “tube” effect built in?

Cheers,
Dean

Bellari - VP130 Tube Phono Stage Headphone Amplifier - $250, Stereophile Class B rated. (i.e., extremely highly rated.)

Some people like distortion. That's like saying some people like dandruff. I am not a recording, electrical or audio engineer. Nevertheless, it is clear to me that live music is the standard. The closer music reproduction comes to the sound of live music the better.

A good tube component, seems to produce a more 'you are there' sound. I've noticed this with tube amps and other components that I've had the pleasure of owning or spending time with (Antique Sound Labs MG S1 15DT, Prima Luna Prologue II, H.H. Scott 380, The Fisher 500c, H.H. Scott tube tuner, Ah! Njoe Tjoeb tube output CDP).

Hi Peter,

You've made many excellent points, and I think the key word here about headphone listening is intimacy because in most cases that is indeed what headphones do so well: they bring the music up closer to you. In part, they do that because they eliminate all of your own room's reverberant contributions and anomalies that occur with loudspeaker playback. Those can really influence what you hear, sometimes positively but often negatively.

I'd also agree with you that headphone listening is great for small solo acoustic instruments like guitar (which I play). Multi-channel surround playback doesn't do much for acoustic guitar, unless you're listening to Spanish flamenco with the musicians and foot-stomps of the dancers recorded in a reverberant live setting. (I've got one such recording and it really comes alive in multi-channel playback.)

You're certainly correct about lots of recording engineers in that they don't always serve the musicians and artists very well. We've all got recordings of artists we've heard live whose CD releases may sound awful.

I'd probably disagree with you on the "you like pickles" I like olives" thing. That analogy, while appropriate for foods and wines, isn't apt for sound reproduction but again my (dare I say it) bias is towards controlled blind listening comparisons of speakers, where, given a few sessions of learning how to describe speaker attributes (positive and negative), most listeners with normal hearing will repeatedly choose the smoothest, most neutral (linear) sounding speakers as the "best" or most natural sounding. (This only occurs, as you know, when the price, size and brand name are concealed from the listeners and the playback volumes are made exactly equal.) I also believe that listeners often accommodate various speaker or sound colorations, whether from their speaker's anomalies or maybe certain traits of tube amplification and come to associate that as their reference--until they hear sound that's stripped of those colorations. But that may take years if indeed it ever occurs.

Anyway, lots of thoughtful discourse triggered by your post.

Regards,
Alan

I received the Little Dot Mk I (the solid state portable version of the lot). It turned out that the "loan" from a friend of a friend became a "never-opened-package" because the guy who bought it realized too late (could not return it) that he did not purchase the tube version. So it is a brand new one I have (and WILL keep!).

I spent 5 hours with it so far, testing mostly with the iPod (3 hours), but also with the receiver (Onkyo 805) for close to 2 hours (1.5 hour music, 30 minutes Blu-ray). Testing were also done with (all Sennheisers) PXC-250 (300 Ohm, iPod headphone, for 3 hours), HD-650 (300 Ohm, home headphones, for 1.5 hours), CX-300 (16 Ohm, iPod earplugs, for 15 minutes), PXC-100 (32 Ohm, iPod headphone, for 15 minutes). Majority with PXC-250.

Some tests were done comparing the trio Direct/Boosteros/LittleDot, but rapidly--because of crystal clear difference--the iPod tests were limited to comparing the impact between direct/LittleDot with each headphone and, for the receiver, between direct/LittleDot with HD-650 only.

Some statements in no particular order (but numbered!):
1) It is now clear that the Boosteros does have some distortion. The improvement when used with iPod and 300 Ohm headphones is sufficient to forget about it, but now I know there is much, MUCH better!

2) Because of lack of rechargeable AAAA batteries (thus stuck buying, throwing away, buying, ...), the difference in cost between LittleDot Mk I and Boosteros becomes irrelevant within six months the latest.

3) With the iPod and LittleDot, there is some difference (possibly a cleaner bass with a hint more dynamics) with the 16 and 32 Ohm headphones, but not really enough to justify carrying another piece of equipment (assuming paying is not important!).

4) With the receiver, there is no difference (at least to my ears) with the 16 and 32 Ohm headphones.

5) The PX250 is now AWESOME! The lack of bass has disappeared (bass is not as strong as the HD650, but it is there and very "tight" and accurate). With the Boosteros, the bass was not improved.

6) To give an example of the overall improvement with iPod/LittleDot, tonight I went (part of the tests), for a 2-mile walk so I could treat me to a beer afterward; I was so enjoying the sound of the combo LittleDot/PXC-250 that I went for 5 miles instead (yes, that means 2.5 beers; well, 3 really if you think about it! ).

HALF-TIME CONCLUSION:
So, if you have (or are considering buying) headphones such as the PXC-250 for your portable player, then it is definitely (without the shadow of an hesitation) a must to move to something at least the quality of the Little Dot Mk I (less than 200$ shipped). I have no idea if other amps are any better, but, for my part, unless I can try one for free, I am TOTALLY satisfied with my iPod/LittleDotMKI/PXC250 and will stop looking for improvement in that area.

Also, the build of this product is amazing. It is very, very pretty. Semi-gloss encasing with brushed metal endings. Sturdy to the bone. I can't image what I would have to do to break it (the Boosteroos is a cheap plastic thing).

Now for the receiver tests...

7) The improvements when using the receiver are much smaller than with the iPod. When there is no or little dynamics, there is no improvement (except perhaps a tad better bass, but I am not sure). So I concentrated on things with big, big dynamics (Italian Baroque, Mozart, Berlioz, Xenakis).

8) The receiver had to be lowered by another 5db (-25db to have the "same sound" as the A1400 at -4db) compared to the Boosteroos. So there's pretty just the pre-amp left to the Onkyo!

9) There is a definite improvement in dynamics with music (significantly more prounced with playing SACDs or DVD-A), but not Earth-shattering (like with the iPod). As the music reaches bigger fortes and fortissimos, the bass improvement becomes clearer. So overall, it is a plus.

10) The more spectacular came when, on a whim, I decided to put some Blu-ray disks (actually, just 2 as it gets boring to rewatch the same scenes a few times! ). "Nightmare Before Christmas" sounds a bit better through the LittleDot, but nothing to write home about (just enough to post here about!). BUT, BUT, BUT, "The Incredible Hulk" provides an as clear-cut case as I had with the iPod. I never knew the HD650 could render big actions scenes like that. When connected direct, the dialog is great; there is a lot of nice details and everything. But with the LittleDot, it's like if there was a subwoofer in the headphones and all the "jump out your seat" sudden changes in loudness is rendered just like that (in the sense of "jump out your seat").

ENDGAME CONCLUSIONS (NO OVERTIME):
Again, if you own an Onkyo 805 with headphones that are 32-80 Ohms (like the Sennheiser HD-595, for example), I doubt there will be much difference; but I can be wrong.

Even if I don't get any more improvement from the incoming Little Dot Mk V (the big solid state amp of the series) currently in custom in Vancouver, it will be enough for me. I would be happy with the Mk I as headphone amp for my receiver, but it cannot be used while connected to the wall (only using the battery), which makes it more-or-less unusable for "living room" purposes.

I never realized just how utterly amazing those headphones were (both PXC250 and HD650). I am currently finishing watching Hulk as I type and I can't believe the level of details they now reveal, especially at higher volume (in the "quiet bits", it is pretty much the same with or without the mini-amp).

I could type more, but I am actually getting tired and contemplating going tp sleep by listening to a nice SACD! And I still have 0.5 beers to drink

Bottom line is: I am very, VERY pleased with this product and recommends it to anyone needing/wanting a small headphone amp but who are, like me, not particularly big fans of tubes (sorry Peter!).

Hope I did not bore too many of you!

Wow! Great info. It’s nice to hear a detailed review of the non-tube version since most of the reviews I’ve seen for headphone amps are tube amps.

Someone's been busy! Seriously, thanks for the great review and thoughts on the Little Dot.