• Welcome to Overclockers Forums! Join us to reply in threads, receive reduced ads, and to customize your site experience!

Headphone Amp mini-roundup

Overclockers is supported by our readers. When you click a link to make a purchase, we may earn a commission. Learn More.


Apr 11, 2006
Well I've only seen one or two people asking about headphone amps here, but since I took the time to put together a mini-review of a few different portable amps I thought I'd post it here as well.

Portable Headphone Amplifier Review

While I may be one of the more knowledgeable members here I do not consider myself a full fledged audiophile, and I must admit that I still have a lot to learn and have yet to really train my ears as well as I would like. But nonetheless my pursuit of audio nirvana continues. This review in essence is just one glimpse at my own journey along this path, and what sounds good to my ears may not necessarily sound good to others, so these are merely my opinions and should be treated as such.

The goal of this test was to look at several portable headphone amps that do not break the bank. As such the most expensive amp I looked at costs a very reasonable $110. The cheapest can be found used for as little as $45, but sells new for about $70. I have used all 4 amps reviewed today with my portable setup and they all perform well there, however for the review I used a home setup to give them the best signal possible and to keep listening conditions as close as possible. I do not have any way to keep the volume static, but I did my best to keep it constant and at a comfortable listening level.

Amps Reviewed:
Little Dot Micro+ Company Info; Ordering Info
Xtra X-1 Ordering Info
C&C Box v2 US Distributor Info (There are 2 US distributors and I purchased my amp from the other distributor, Soundwise on head-fi)
Mister X XP

Test Setup :
Transport : Philips DVP-642
DAC : Upgraded Zhaolu 1.3
Interconnects : Blue Jeans Cable digital coax & Soloz Audio silver RCA-mini
Sennheiser HD580 heaphones with HD600 grills & HD650 cable

Test Albums :
Erich Kunzel and the Cincinnati Symphony Orchestra: Tchaikovsky’s 1812 Overture
Track 1:
Tchaikovksy’s 1812 Overture is one of my favorite classical pieces. It starts out smooth and detailed and erupts into an explosion of energy at the end. It is simply an exciting piece of music to listen to. This particular recording is quite detailed and interesting as it utilizes real cannons and bells near the end of the recording. This is probably the most energetic and fun to listen to recording of the 1812 Overture I have come across.

Massive Attack: Mezzanine
Track 7: Man Next Door
Massive Attack is a group that I have only recently discovered. They show influences of jazz, hip hop, reggae, rock, electronica, and even classical. This is a very interesting disc to listen to and is also good for testing audio equipment.
Man Next Door has deep synthesizer bass, smooth vocals and is a great track to distinguish stereo separation.

Staind: Chapter V
Track 2: Right Here
This CD is probably the most well known disc chosen for this review. I have been a long time Staind fan and Right Here, while not one of their most popular songs is one of my favorite. The guitars are grungy and the drums tight. Cymbals are also strong and can easily be fatiguing if the source or amp are too bright.

The Amps:


Cost: $71
Op-amp: MAXIM MAX9724
Battery Life: 100+ hours

The LDM+ is housed in a small metal case which is pretty durable. It comes in either Silver, Gold or Black and is bundled with a mini-mini IC and a power pack. The amp itself is rather handsome and resistant to scratches. I am the second owner of this amp and I have had it for about 8 months so it has seen many, many hours of use. The best feature of this amp is the battery life, which is simply amazing to say the least. Battery life easily tops well over 100 hours. I have charged my LDM+ probably no more then 3 times since getting it. Build quality is about a B. It is durable, but not the prettiest amp of the group under review. The mini-mini IC that was included is lacking. It was far too long to be used for portable use and was not high quality. I have heard that an upgraded 6” mini-mini IC is now included. The LDM+ does have a faint turn on thump.

The LDM+ is a great little amp. It is probably the most neutral amp in its price range <$75 including shipping. However, it is not the best sounding amp reviewed today.
The LDM+ had only mediocre performance with this recording. There was good bass extension, but it was not well defined. Some of the instruments seemed to blend together more then they should at times. The highs were a bit tinny. Overall the mids are the strong point with this amp. Overall the LDM+ was just a bit shy on dynamics to make this piece truly exciting. The cannons and bells were a little dull.
Massive Attack
The LDM+ does a pretty decent job with this track. Bass is strong, but not very tight, neither is it bloated though. The vocals are a bit grainy, but not bad at all. The big disappointment here is in the stereo separation. This track makes ample use of both channels and often plays different instruments through each channel or sweeps back and forth. The LDM+ was by far the worst amp in this review here. It was almost as if the LDM+ had some crossfeed enabled, which it does not.
The LDM+ did a great job with the bass on this track, but the cymbals were a bit shrill and fatiguing. The vocals were not as clear as some of the other offerings.

Xtra X-1

Cost: $93 plus AC adapter
OP-amp: OPA2134
Battery Life: 20 hours

The X-1 is probably the smallest amp reviewed and it came in the most attractive packaging. Color options include the standard Black and Silver, but it is also available in Blue. Included accessories: mini-mini IC, wallwart, pouch to carry the amp and protect it, & box. One important thing to note is that the wallwart has the European style plug so you will need to get an adapter to plug it into a standard US AC outlet. These can be purchased from Radio Shack for around $10. The mini-mini IC is better then the one supplied with the LDM+ and the included pouch is very nice. I wish the LDM+ came with a carrying pouch. The faceplate of this amp is different from all the others in that the volume pot is located in the middle, in between the input and output jacks. This can make it difficult to change the volume if large plugs like the Canare F12 are used. The power switch is not built into the volume pot but instead there is a small button to turn the amp on and off. The only problem is that it is located on the back plate of the amp. If you plan to carry the amp in a case like I do then this means you have to physically take the amp out to turn it on and off. I am the second owner of this amp, but combined usage between both users is around 100 hours so it was well burned in before review.

The Xtra X-1 is a fun little amp. Of the group it is probably the least neutral, but it adds a punch that makes this amp very fun to listen to. Being the second cheapest amp reviewed it is still a good value for your money, but if you plan to use the amp for critical listening then you should look elsewhere. If you want a punchy, amp to enjoy your music on the go then this just might be the amp for you.
You can defiantly tell that this amp has a bit more slam then the LDM+. Bass seems to be a bit rolled off, but you can definitely tell it is still there. This may be due to what would appear to be a slight boost in the frequencies around 100Hz. This gives the upper bass a lot of slam. The highs are not as tinny as on the LDM+, but they are far from smooth and silky and I would still consider them shrill. The amp does not handle great separation and some of the instruments again seem to get lost amongst one another. Overall a fun experience with the cannons even though the bells seem to be lost at times. Not a very critical amp.
Massive Attack
Here the huge synthesizer bass seems bloated and grainy. Stereo separation and definition seem to be lost as well. Once more this amp makes for a fun listening experience but is not detailed at all.
Once again this is a bassy amp. Bass and lower mids emphasized leaving the upper mids almost undistinguishable. Highs are tinny.

C&C Box v2

Price: $112
OP-amp: AD8532
Battery Life: up to 70 hours, but 30-40 is more likely

The C&C Box v2 is a relative new amp that has only recently made a splash in the US. There are currently only two North American distributors. I purchased mine from a group-buy on head-fi at a slightly reduced rate. Physically the case used for the C&C Box is almost identical to the LDM+ only longer. Also, the paint used is different. While the LDM+ has a flat black, the C&C Box is glossy. Overall it is a very attractive looking amp. The C&C Box comes packaged with a wallwart, mini-mini IC, carrying pouch, and a certificate of manufacture.
One thing that quickly sets the C&C Box apart from the other amps reviewed is that there are 3 switches located on the back panel along with the power jack. These are labeled as: MF, LF, & SF. According to the distributors MF is for vocal enhancement, LF is bass extension and SF expands the sound stage. All 3 switches have 2 positions off and on and you can use any combination to suit your liking. Personally the only switch I feel makes any good improvement is the one corresponding to sound stage expansion.
I should add that one of the distributors has packaged the box in a very attractive box while the other has not. My amp came with slight imperfections to the paint on the back plate and in no way affect the sound, but being the perfectionist I am I contacted the distributor about this issue.

Overall this is a very nice sounding amp that shows potential for greatness. I have used this amp quite a bit in my portable rig and have been impressed and greatly enjoyed what I heard. As previously stated the SF switch does appear to give the music more dynamics and an enhanced sound field.
Sadly, I was not able to perform the same listening with the C&C Box as I was with the other 3 amps reviewed today as the amp simply could not handle even the low level line output on my Zhaolu DAC. The amp was driven to clipping and resulted in crackles every time the bass hit. The 1812 Overture was the only test track that was listenable and then only before the cannons kicked in. But during the brief time spent here are my thoughts.
The C&C Box is very pleasant to listen to, but has a loud turn on thump so it might be a good idea to turn the amp on and then plug your headphones in. It is not quite as detailed as the XP and it does not have the slam of the X-1. But it is a fairly detailed amp nonetheless.
I have talked extensively with the distributor and am currently waiting for an update to be done to this amp. Apparently there is a new revision under way with a switch to allow the amp to accept a stronger input signal. Hopefully I should be able to get my hands on a revised amp in about a month and be able to complete the review.

Mister X XP

Price: $110 plus shipping
OP-amp: AD8397 as tested (also available with
Battery Life: 8-12 hours as tested

Mister X’s XP amp is a PINT class amp meaning it is similar in design to Warren from tangentsoft’s PINT amp. The XP is newer and updated but has the great sound quality and energy of the original PINT that made it popular. While the other 3 amps reviewed are of Chinese design, the XP was designed and made in the US by a prominent member of several online forums. This amp can either be purchased as a complete amp or as a pcb to build your own. I purchased a completed amp and a board to try the build myself. This is not a build for amateurs though as it involves smd soldering.
The XP is housed in a Hammond aluminum enclosure and comes in either Silver or Black. The XP is probably the most durable amp reviewed, but it is also slightly larger. It comes with only a wallwart. No other accessories are included so you will need some sort of IC to use with it. It is also worthy to note that Mister X builds these amps per order so lead time can be up to 2 weeks. It took about a week for mine.

The XP was by far the most detailed amp reviewed. It sounds the most like my home amps, and for a solid state amp sound surprisingly similar to my Little Dot II+ in some regards. It is warm and detailed. There is no turn on thump at all. While the XP may not be as exciting as some of the other amps, it is by far the most detailed and is fairly neutral as well.
The XP tackled this recording with ease, showing the most instrument separation out of any of the other amps. The sound was very smooth with warm mids. It sounds a little less dynamic then the X-1 or LDII+ almost like the op-amp could have used a bit more power, but still very good. The amp handled the cannons very well and gave them a nice impact some of the other amps did not have.
Massive Attack
The track opens up with deep, deep bass which the XP handled nicely. Bass was strong and tight. It was not bloated like some of the other amps. Overall the XP has the best bass in my opinion. The vocals were very smooth and the XP was the only amp to really handle the stereo separation of this track well.
The XP handled this track the best out of the amps reviewed. There was good instrument separation, tight bass and smooth vocals. Cymbals were crisp and clear without the harshness exhibited by the other amps. The XP is very enjoyable for rock. When the track was over I just wanted to keep listening.

Overall I would have to say that Mister X’s XP amp is the best. It is head and shoulders above both the Xtra X-1 and LDM+. It is by far the most detailed and analytical amp of the group. It is larger, but not huge and still easy enough to use as a portable amp. The only downside is the battery life, which is not very long, but it lasts long enough that if I charge it about as often as I charge my Zen Vision:M I won’t have to worry about it.
The C&C Box was a bit of a letdown. I wish it did not clip from the line out on my Zhaolu, which does not really even have very strong outputs. I am looking forward to getting my hands on an updated sample to look at.
The Xtra X-1 is a very fun amp to listen to, but is not detailed enough for me. If you want a fast amp to enjoy your music on the go check this one out, but if you want to critically listen or listen to bassy music you’ll want to look elsewhere.
The LDM+ is a great amp at its price point, but the extra $30-40 to get a better amp would be worth it in my opinion

Out of this group Mister X’s XP is the clear winner. The C&C Box shows promise and hopefully I will be able to do a face off between the two either with the new version of the C&C Box or possibly with my Zen Vision:M as the source to even the playing field.
Albaholic said:
Very nice review. I'm looking to get an amp to go with my HD600's

they're basically HD580's which I used for this review. So any of the better amps here would be nice. If you want a home amp that won't break the bank you can buy or build a PIMETA. My maxed out PIMETA that I built ran me somewhere around $150-200 for parts, but I kinda went all out. I also have a Little Dot II+ tube amp that goes nicely with them.
That's what I was gonna go for. :D the Little Dot that is. There's gotta be more audio freaks on here :p
I am starting to rebuild my audio up. Just got me a Cowon U3.

I lost my setup a number of months ago and kinda gave up on portable audio. I could not resist any longer.

Next is the AMP then grab a good set of cans and a better set of earbuds(the Senn MX500's arent cutting anymore). I might also grab a good set of phones for when I dont need ot tuck the buds in my pocket and the cans are too big.
Albaholic said:
That's what I was gonna go for. :D the Little Dot that is. There's gotta be more audio freaks on here :p

yeah, it's a pretty decent amp and was my first amp. :D I'm selling mine. I didn't post it on here yet, but I posted it in my big fs thread on ocn.