This is a wonderful little tube amplifier for the price. I paid only $59 for the amp and it was in perfect condition with a new Electro-Harmonix 6922 tube. The tube itself runs about $15, so the actual cost of the item was only roughly $45 (minus the tube). For that price, it is a well made, extremely well priced amp, and the value you get is superb.
 
Initial impressions - the amplifier is a more "DIY" open design, with no shielded case. This is fine considering the price. The actual build quality is great: solid soldering, and good quality parts. The gain potentiometer, for example, is an ALPS pot which are known to be high quality. For the price, this thing is built to a great standard. Doesn't come with very much extra: the power supply, amp, and the tube. Simple but efficient packaging. Two LED lights (blue and red, one signifies power - the red - and the blue is for the tube attachment, which draws voltage from the capacitor and can stay on for a few seconds after the tube is unplugged due to the capacitor holding some charge).
 
I've driven higher and lower impedance headphones. Most of my cans are low impedance, and this amplifier worked wonderfully for anything I threw at it. It states an output range of 20-600 Ohm, so that is pretty flexible with regards to driving cans. I don't have a pair of high impedance (600) cans to test with, however it should work fairly well for most cans on the market.
 
Sound quality is warm yet clean with no distortion or any real noise, which is something I would expect from a tube amplifier that is fully Class A driven. The amplifier comes with a 3 band graphic EQ, which is passive. This is pretty cool and adds some character and optimization potential to the amplifier for sure. Putting the settings all the way to max is basically the "0" setting since it is a passive switch; there's no "added" frequency adjustment, simply subtraction (not allowing certain frequencies through). Similar to a passive volume attenuator. So unlike a more traditional, non-passive EQ switch where the lowest setting is the default, the maximum up setting for the EQ is the technical default and lowering the switches simply attenuates the frequencies without distortion. This is a nice feature. Works well because you can adjust to your desire, and it's very flexible. 
 
Amp can get a little hot, but this is expected, especially because this is an open case design. The heatsinks are what really get hot, which hold the rectifiers, which are power MOSFET's so they have a bit of heat. Nothing unexpected, just gets a little hot but nothing too crazy. I can still touch the EQ sliders just fine, but obvious caution should be applied as it is an open amplifier chassis. The tube itself is only somewhat hot; it is the heatsinks of the rectifiers that really bear the most heat load!
 
 
Since this is an open case, there is some EMI/RFI (electromagnetic/radio-frequency interference). This is solved by keeping things like cellular devices a few feet away from the amp, putting the amp in a solid, EMI shielded case (such as one made of solid aluminum or related materials), or placing it on a shielded surface. By doing this I easily get rid of the EMI/RFI. Part of the EMI/RFI is also due to the power cord, which is not grounded, but this is easily minimized to a significant degree with the methods I just mentioned as well.
 
Overall, I give this amplifier a 5/5. For the price to quality ratio, this thing certainly performs with flying colors. An excellent starting tube amplifier that gives the warm, crisp Class-A driven sound quality expected from a tube at a very accessible price point.  Some photos below (click to see higher resolution). 
 

 

 

 

First and foremost, I have experience with several different headphones, namely much of the Ultrasone series (Pro 900, Pro 750), Denon D2000, D5000, and Fostex TH600. I mainly deal with closed back headphones because of the utility that I generally use headphones for, and the privacy that closed back designs provide. I am well aware of the shortcomings of closed back cans, however this review is going to really focus on the headphones themselves rather than a closed vs. open debate.
 
Audeze's "cheapest" headphones to date, the EL-8 series, are certainly good contenders in their space. The EL-8 closed (EL8-C) is a well made device. Some have disagreed and stated the user of cheaper veneer wood; while this could have certainly been improved on I think Audeze was trying to separate this headphone from their much more expensive series. I personally think the wood accents are well placed, however this is purely from a design standpoint. The entire casing is mostly metal/solid and the headphones are heavy at 480g for the EL-8C. Surprisingly, I like the heaviness of the product, especially the solid nature of the entire headphone: it feels very good in the hand and does not feel like it will break. Compared to many other headphones, this one is very proprietary with custom connectors for the left and right attachments. I confirmed with Audeze that replacement/extra cables will be on sale soon through their website, as well as balanced cables for the EL-8. It seems Audeze has taken an Apple-style approach to their newest headphone as it is one solid piece, essentially. Not much can be easily done, but I don't have much to complain about. I wore these headphones for 10 hours straight several days and I did not have an issue with comfort, in fact these are some of the most comfortable headphones I have worn. The weight doesn't bother me and the large cup size is perfect. Yes, it's not real leather on the cups, but the material is well made and cooling, and comfort is no issue. Furthermore the cups are very nicely attached to the entire product, making for a solid device in the physical aspect.
 
 
Onto the sound: these headphones are different from most of the headphones I've experienced in that they are planar magnetic headphones with magnets aligned such that they create a large magnetic flux from essentially the same size magnet as a smaller driver. For the EL-8C, I found it VERY important after listening for many hours to have a tight, closed seal on the cups to ensure the soundstage remains clean. These headphones are very sensitive to 'openness' and wearing them too loose drastically impacts the lower end and overall soundstage.
 
When I first got these, I plugged them into my iPhone and listened to a few lossless files without any amplification. This was to test the wide claims by Audeze that these are easily powered by a device like an iPhone with no amplification. At 30 Ohms and 100 dB/mW, these are pretty sensitive and low powered cans. This was true, but as usual I am used to the significant increase in performance from proper amplification, so my next test and all listening thereafter was done with amplification. I used the Fiio E17 amplifier primarily for my listening; I did also have a JDSLabs C5 amplifier but I found the Fiio to be more suited to these cans. My DAC is an audio interface from Focusrite, and I ran a passive attenuator to control the volume. 
 
Comparing these to the Denon D5000 or the Fostex TH600, these are very different soundstages. The Denon/Fostex both have very strong, punchy bass. The EL-8C's don't have that punch, and are not going to provide that "banging" experience. These are very balanced headphones, if one wishes to look at the graphs Audeze provided for their EL-8 open series you can see that there is essentially flat response from 10Hz-7,000Hz with a slight dip at the 7KHz mark - not sure if this is the same with the EL-8C, but I don't really look at frequency curves for headphones with as much rigor as speakers because there's no set measurement (Audeze used a specific device, but every ear is different, and there's no perfect positioning that can be guaranteed). 
 
With a bit of tweaking with the Fiio E17 amplifier, which has a nice amount of EQ (bass and treble, stepped adjustments with a lot of flexibility) I was able to get these sounding pretty damn good. I set the bass to be boosted quite a bit as I am used to harder hitting cans and a slight increase on the treble. The mids on these cans are very clear, something that planar headphones are well known for.
 
These are very "flat" headphones without any EQ/amplification and whatnot, and may not provide what every listener wants. It's a unique style with new elements from Audeze, and the structure of the headphones requires a tight fit - moving positions on my head I was able to find the correct fit for the soundstage I wanted. This may seem odd, but these cans are very sensitive to different positions and tightness and finding the right fit is key. Once that is done, and EQ/amplification is added, the EL-8C performs beautifully. Note: EL-8C will still *NOT* have the same bang as the D5000 or even the Fostex TH600 with regards to punch on the bass. Rather, the EL-8C will provide, with proper EQ/amplification, a solid, stereo-like soundstage with good, clear bass, crisp mids and clean treble. 
 
The best way I can describe the soundstage is to that of my main studio monitors, PreSonus Sceptre S8's which are co-axial and have an extremely well rounded stereo soundstage. These EL-8C's, although not loudspeakers, provide that "360 degree" soundstage around my ear. This is the difference I found between the Denon D5000 and Fostex series vs. the EL-8C: if you're looking for pure bass impact, then these are not the cans for you. If you want amazing sound isolation, a stereo soundstage and (with proper EQ/amplification) good, clear bass that is pretty heavy hitting with mids and treble in a nice sync then the EL-8C's are for you.
 
I would also quickly like to mention the sound isolation on these things blows many of my prior headphone experiences away: these things are extremely snug, isolate noise very nicely, and that's a huge plus in my book. It's also obvious that the soundstage is determined on the right fit as I mentioned, so these things are certainly proper closed back circumaural headphones with large pads. Excellent sound isolation on both sides, and very little leakage when comparing these to other closed back headphones.
 
For value, I got these at $599, $100 less than the MSRP because of an open box deal, which was essentially new. So I am happy with the price I paid, especially considering these are new headphones.
 
The few cons I have: takes a while to get used to the sound of these planar cans, and also requires a lot of burn in, EQ, and proper amplification pairing in my opinion, even though technically these work fine with no amplification. This takes a bit of time. Also, the connectors are proprietary and not the most snug, but I haven't had much of an issue, though there have been times where these connectors have been sort of loose. As noted in the beginning of this long review, Audeze is going to sell cables for these things (including balanced ones) and they told me within 30 days or so (probably end of May). Should be interesting to see what they have in store.
 
 
To conclude: if you are looking for the classic sound of the Denon D5000 or similar Fostex TH600, or even something much more bass-centric like Ultrasone Pro 900's, these are not going to provide that "kick." With a little bit of patience, tweaking settings and finding the right fit, however, the EL-8C shines and has its own place on my desk as well-built, comfortable, very dynamic headphones. Certainly a great purchase, and I am happy with the overall product. There are places for improvement, and it does take effort to get the sound to what you may desire, but once you get the sound and physical fit right listening to these things for hours upon hours is seamless, clean, and a comfortable pair of closed back headphones with technology that is still fairly new in the respective design.

Excellent closed headphones. I primarily listen to bass-heavy music (deep house, tech house, etc.) but I do enjoy many other genres. That being said, I was very pleased with the Ultrasone Pro 900s which are known to be excellent for the deeper side of music. Indeed, the Ultrasone 900's are an excellent pair of headphones. The bass hits hard and the highs are very bright. The mids are what I'd expect from headphones with a driver emphasis on the highs/lows (for specific genres this works well). After some experience with Denon's old AH-D series (D2000/5000) I was looking to see if I could find a headphone that could contend the Ultrasone 900 "bass monster" while providing the comfort of the Denon design.

Now to the Fostex TH-600 - I recently picked up these headphones as they looked to be a good contender to the Ultrasone 900s. Price range is higher but that was to be expected as the TH-600 is a step up in hardware and soundstage. The 900's are very hard to beat -- I've tried out Denon AH-D2000's before and found them to be very comfortable and nicely designed yet too balanced for my taste.
 
I got a great deal on these cans - under $700 new - so the value is great, especially in this case. On to the review ----
 
 
The Fostex TH-600 provides everything I was looking for in an upgrade from the Ultrasone Pro 900s:
 

1. Significantly increased comfort over the Ultrasone 900s these use almost the same body as the Denon D5000/7000 as Fostex designed those except the TH-600 has a solid magnesium frame that feels very good in the hand - I am going to be upgrading them to Lawton Audio wooden cups shortly, however, as wood is still superior to the material used on the 600's. Nevertheless, the material used is much, much better than the plastic on the D2000 and plastic in general. It's a good contender to wood but the specificity and lightness of wood extends the soundstage and helps the bass stay tight - something that is important in the genres that I mainly listen to (deep house, tech house, etc.). Also waiting for Lawton Audio's Angle Pads to arrive which should be a nice upgrade to the leather pads they provide, although I'm happy with the comfort (always looking to get better!)

 

1. Powerful - driver is very powerful at 50mm/1 tesla - very versatile

 

1. Better soundstage - while the Ultrasone's are still power machines and great headphones, the TH-600 really takes that to another level. The bass hits clean and hard. With the amplification in place and proper sound files music sounds amazing. Very natural but powerful and crisp. The sound is extremely clear and the frequencies are distinct. Mids are not recessed, highs are not too bright. Everything is in place and hits perfectly. The design of the headphones creates a very natural sound while maintaining clarity. Adaptive to multiple genres of music too as it holds a good soundstage for most types of music. I am excited to try out the wood cups that I will be modding in the next 6-9 weeks once they arrive - should make the excellent soundstage even better.   These headphones are better than the D5000 (for my musical taste) in my opinion even without the wood however the D5000s are very good and the closest thing I've heard to the TH-600 - I've listened to both and the TH-600 has better bass response without being too bright on the highs. I haven't heard a D7000 so I can't speak on that but comparing a D7000 to a  TH-900 would probably be a better side by side for those cans vs. the 600s which are priced somewhat similarly to the D5000s current market price.

 

1. I would strongly recommend amplification for this as it really improves the experience. At this price range headphones should have some type of amplification to utilize the power. Without an amp (or an AMP/DAC) these sounded dull to me (as expected). I always used my Fiio E17 with the Ultrasone headphones as they too need ample power to show their true potential. This is a popular portable headphone amp that will provide plenty of power for these cans (E17). Personally I have been recently using the JDSLabs C5D AMP/DAC and it has replaced the E17 for my portable amp use as I prefer the product over the E17 and have had good results with it. This is of course preference and there are several threads on this forum discussing the different AMP/DACs including dedicated ones for the Fiio and JDSLabs C5/C5D.

 

1. It also comes with a non-detachable cord which is very long with a 1/4" output -- if you wish to use this with a 3.5mm you'll need an adapter. Personally this is not an issue for me as I can easily adapt if I need to with a proper grounded adapter and the 1/4" works well in the studio natively with all the equipment.

As with any new headphones I'm still burning in (have had for about 2 weeks) but these are excellent so far and I'm really enjoying it. If you are looking for a pair of headphones that has an excellent low-frequency response, clear mids and sharp highs while still adaptive to many genres of music (much more so than the Ultrasone's which are very bass heavy and muddier in comparison - works well with some genres like EDM but not so much with others) the TH-600 is a great choice. Well worth the price (I paid $699).