Is it worth buying a headphone amp?

I currently have the Sennheiser HD555 (modded to HD595), and I'm trying to figure out if it's worth buying a headphone amp to get better sound out of them--or if I'm better off investing in better headphones first. Right now, I'm using the headphone jack on my NAD C372, which has very high 220 Ohm output impedance (the Senns are 50 Ohm). The sound is a little thick, dry, and lacking in microdynamic detail. If I get a headphone amp, I'd run it through the tape out from my amp. I'm considering the Schiit Asgard, as I'd like to buy American and $250 is right on the dot for what I want to spend. Any other suggestions?

I should note that in the past I have owned some pretty good headphones (Senn HD600, AKG K501, Etymotic ER4P). Sold them and downgraded when I wasn't using headphones as much as I am now. If I do decide on new headphones, it'll probably be a used pair of HD600 or K702 with an amp for them further down the road.

Thanks for your thoughts!
You will probably get more informed opinion over at headfi.
The only amp that I know of that really makes headphones shine is a Cary SLI80. Other than that I would go with a headphone amp. Especially if K702 's might be in your future. The K702 's require some serious guts but you will be rewarded. Headphones are an after thought for amp manufacturers.
Agree the headphone amp in most equipment is just an afterthought.
A $300 headphone amp would do the job much better.
I would go to Head-Fi dot com to see what those guys are using.
That is THE place to read about headphones and headphone amps.
Those are pretty good headphones and would likely benefit from a good headphone amp. Liz gave you some good advice, check with the dezizens at and you'll get some good advice on the proper amp for those 'phones....

Try some Schiit. It's pretty good bang for the buck and while the brand is new, the founders have been involved in some great companies before and bring something to the table.

Not too pricey either.
I just upgraded from a Maverick Audio D1 DAC/Headphone amp driving Sennheiser HD 545's to a Peachtree Audio MusicBox driving Sennheiser HD 598's.My headphone usage has gone from must use so as to not disturb anyone during the wee hours of the mourning to can't wait to throw them on & rock out so I would answer a resounding YES to your question!
In addition to check out,, &
Sell the NAD and buy a Portal Panache; great integrated with great headphone jack, no remote or features, but great sound for the money.
Thanks for the responses, folks. It seems like a headphone amp will benefit me greatly, but I'm still wondering if I should buy better headphones first. I did a little experiment this morning and plugged my Senns into my Macbook (I'm not a computer audio guy yet) with its output impedance around 30 Ohms, and despite the crappy sound card the sound was worlds better than it was through my NAD. Still not a great impedance match, but it was better.

Though the bass was diminished when plugged into the laptop (I think the impedance mismatch with the NAD emphasizes the mid-bass because of the Senns' high impedance spike around 100Hz), the mids and treble were clearer. Cymbals sounded like metal rather than papery electronic hash, though resolution still wasn't excellent. A brushed snare on Lucinda Williams' "Fruits of My Labor" sounded like vague background clatter (think paperclips being shaken in an empty OJ-concentrate can), while it resolves perfectly through my speakers. Not sure if that's a limitation of the headphones, though I do see that they're capable of better sound than I was getting.

The Portal Panache is new to me and looks like a great product. That might be a good future upgrade for me. For now, it's a little out of my reach. I've read a bit on Head-Fi but haven't joined yet, so I appreciate everyone's input here. Still don't know if I should put the Schiit or headphones on the list first (ideally I'll eventually do both)--but I'm open to further suggestions! Admittedly I'm still not a huge headphone fan, as listening fatigue sets in pretty fast for me even at low volumes, but they're good for keeping peace with the neighbors.
Headphone amps are a lot of fun. I WOO Tube headphone amp. You can play with the tube amp by "rolling tubes" which is trying out different types of tubes.

My headphone amp is in the office and part of a computer audio system.
Well, folks, new headphones it is. The HD555 are excellent for the money, but to start with I think I'm to going sell them and look for a used pair of AKG K702. I'll buy an amp later, when my budget allows. The Schiit Asgard is still at the top of my list, though I am concerned by the 6 Moons review, which characterizes it as being a bit lean--and lean is the opposite of what I want in a headphone amp. Any other suggestions around $250? Thanks for the input, all.
I don't own a headphone amp but if you feel like practicing your soldering skills the Bottlehead Crack gets great reviews.
O/P,I suggest you research your choice of headphones carefully.Everything I have read on the AKG lineup points to them being on the brighter side of neutral.If you were to think in terms of nature, AKG's are characterized as being a clear,snow covered day as opposed to Sennheiser's which are usually described as a deeply colored sunset.The new HD598's can be had for your budget & after around 300 hours break in time they are simply wonderful,having that warmish Sennheiser tone but with a slightly less veiled midrange than the 600 series.JMHO for what it's worth.
That's true until AKGs are broken in. Also personal preference. I have experience with HD650 and K702 and to my ears after a year the K702's are much better and tons cheaper. That's me though. My hearing is shot. Im sensitive to bright and that only describes new AKGs. Zero bright when broken in.
I appreciate the cautions about the AKGs. I am a little worried that I might find them lean or bright, and due to geography I'm not going to be able to audition them before buying. That said, I thought the AKG K501 was a pretty amazing headphone when I owned it. Its treble was more present than Sennheiser, but I wouldn't have called it bright the way I would for something like the Etymotic ER4P (I got rid of those after a month or so). The K501 did need a LOT of break-in, which I understand is true of the K701/2, too.

I know I really liked the HD600 when I owned them--deeper bass than the K501 with a warmer and smoother sound overall. I might just buy another HD600, except for two things. One, used prices for the HD600 have seemed to rise a bit lately, making the K702 the better value. And two, I just plain think the K702 looks cool! Probably the wrong reason to buy headphones unless I listen in front of a mirror, but still...
The Music Hall PH25.2 is a very good tube based amp in your price range.
Watch the prices fluctuate on Amazon. The AKG K702 is going for under $280 right now and I don't think you'll ever see them for less than that. That price will change fast.
I listen to Sennheiser 650's with a seperate headphone amp and it is the best sound I've ever heard. I have a pair of Sen. wireless phones which I use when my wife doesn't want to hear the stereo or tv. These are MUCH less expensive than the 650's, yet unless you A,B them to each other, the wireless phones are very, satisfying. I suspect your headphones will pleasantly surprise you when you get a good headphone amp. Senns are very musical.
I hope you also have loud speakers as well. You know about the dangers of extended headphone listening doctors are warning us about...

I find that with the better rich quality sound of a tube headphone amp allows me to enjoy at a lower volume, which adds to the safety of headphone listening.

However, since we all want to enjoy this sonic heaven all of our lives, I advise all to give up headphone listening, and get a enjoyable loud speaker set up.
The K702 are the best bargain in high-end headphones. They are open and clear and fast and musical and to my ears simply blow away anything in their price class. Yes, it took over 300 hours of burn in to fully tame the initial high frequency brightness, but after that you're in heaven. You'd have to spend way over $1000 to get sound this good, and, they are so comfortable I can wear them for hours.

I feed them from a Ray Samuels Audio tube headphone amp called The Raptor, which costs $1200 and is just magic with the K702s... Close your eyes and you're gone! Ray has a SS amp that is in your budget, but I highly recommend you hear them with tubes before deciding. Buy used and you'll be surprised how much you can get for your money.

Update: I sold the HD555 and bought a mint pair of HD580, which hadn't even been broken in and already sound fantastic. The upgrade is significant--the HD580 sounds very much like the HD600 I used to own and is a much more refined headphone than the HD555. Bass goes deeper, midrange is much more natural, and highs are grain-free.

As far as a headphone amp goes, I may buy one later on but have found a great solution for now. One of the problems with the headphone jack on the NAD C372 integrated is that the gain is so high that 'phones are either too quiet and unbalanced or way too loud. Luckily, the amp has a second set of pre outs with variable gain. I've run a set of IC from that pre out and attenuated its gain by about 6dB. Now I can turn up the volume knob into a range where it works better, and the headphone sound is great.

My speakers sound better this way, too. Before, I could never go past 9 o'clock with the volume, and now I can turn it up toward 10-11. The headphone sound is a bit cool and dry, but the whole amp sounded that way when it was new, and the headphone stage hasn't been used enough to be fully broken in. I'm going to break it and the 'phones in over the next couple of days.