ESS 422H AMT Hybrid Headphones

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I really like the sound of my ESS Heil AMT-1 tweeters. ESS now makes a hybrid headphone using AMT technology. It has a dynamic driver for bass, so it’s a 2-way headphone. Looks well made with walnut cups, real leather pads, metal hardware and removable cord. One complaint was that they are heavy - with all that wood, leather, and aluminum. However, all those premium materials make it feel very well built and high quality. Almost no plastic used.

ESS 422H Hybrid Headphones | ESS Laboratories, LLC

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Has anyone tried these?

They appear to be on sale (direct or Amazon) at an introductory price of only $149. Not bad for a 32ohms impedance rated at 110dB/1mW.

Some reviews:
https://theaudiobeatnik.com/ess-422h-headphones-review-high-end-sound-at-an-entry-level-price/

ESS 422H Headphones - Reviews | Headphone Reviews and Discussion - Head-Fi.org

ESS 422H Headphones Review | Headfonics

ESS 422H Headphones Review

I heard some reviews where they say it makes a difference if your model has the tweeter on top and the dynamic driver on the bottom. It’s interchangeable but makes a big difference. Mostly positive reviews. Also customer service seems to be very good too.

Here’s a sneak look at the insides from a Head-Fi post:
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I see a single SMT cap as a high pass filter for the AMT and the dynamic driver runs full range.
 
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This is quite interesting!
I think I have seen a few headphones that have done this, but as far as I can remember, they were not really good.

There are some benefits with multiple drivers, the main advantage of having reduced distortion thought the FR(in case of headphones it mainly in low the end, aka. bass region).
Average dynamic headphones today already have around 5%ish of THD(because the front is sealed and driver is so close to the ear, getting decent bass with fullrange driver is not a big problem) at 20Hz, a number that drastically gets better around at 50Hz etc.
But today most of the high end planar magnetic headphones, have very low THD at sub-bass by default.

I don't see many advantages of this approach and many potential headaches, but it might help with reducing cost of headphones in future which is something everybody can look forward too!
 
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Strange, but I like the palpable, visceral feel of bass from my cans with dynamic drivers (Status OB-1) over the bass of the membrane drivers (HiFiMan HE400i). I have listened to Focal Utopia, which is a dynamic driver headphone, and it sounds very good everywhere. However, probably lacks the top end air of the HE400i. I am wondering if this can bring together the best of both worlds? Replacing that little ceramic MLCC cap with an appropriate MKP film cap probably can do wonders for the sound.
 
I have not heard heard Utopia, but I did heard Elex and indeed it has a very nice sounding bass, very punchy and visceral and I think that is due to the rather unique driver.
For example LCD 2 and HE1000 put all dynamic drivers to shame in sub bass region.

Playing with EQ on LCD2 and adding +10dB around 20Hz and they didn't sound bad or distorted like dynamics do when you EQ them in that region... I was blown away...

This could theoretically give you the best of both worlds, albeit hard to pull off IMO. I like companies exploring these options.
 
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Test of the ESS 422H

I just got my new ESS 422H AMT (32ohm) headphones yesterday and have put it through its paces. Listened to it on various amps (DIYA SE Class A and commercial Class AB) and compared against the rest of my phones: DT880 (250 ohms), HE400i planars (32ohms), Status OB-1 (55ohms), and Audio Technica ATH-M30x (55ohm). Build quality wise, they exceed all the others by several orders of magnitude. All walnut, heavy cast zinc or aluminum frames, either pleather or leather earpads and headband, textle covered cable with walnut grip on 3.5mm jack. They look and feel like $600 headphones, not $150 headphones. The detailing in the metal castings that hold the wires internally so there are no loose wires visible on the headband or yoke is really nice. The metal works looks like an investment cast piece of sculpture. They come in a nice box and there is a nice zippered compact carrying hard-case covered in ballistic nylon.

I listened to them on the Desktop Class A ( big PCA with 130mA bias current and 21v rail), a Fiio A5 (LME49600 Class AB with Muses opamp gain stage), and Aksa's Silicon Harmony (SE Class A with 1200mA bias current), and finally a Cavalli Tube Hybrid (CTH) with tube front end and SS output stage. All of the amps sound great but the Silicon Harmony wins here of course.
I let them break-in overnight playing some bass heavy pop music. Not sure if that did anything but wanted to give the suspension on the dynamic driver a chance to soften up. So far, they sound amazing and have more detail and resolution than any of the other headphones without being fatiguing. They will reveal flaws in the record that you did not hear before - mostly because they are 110dB/1mW sensitivity. Sort of like balanced armature IEM's in sensitivity which is crazy. Don't take much power - so the amp doesn't work as hard. Less distortion from the amp.

The sound is balanced and works for all genre's: jazz ensembles, girl and guitar, heavy metal, pop, dance/hip hop, classic rock, folk male vocals, folk female vocals, strings chamber orchestra, Hans Zimmerman movie sountracks, and orchestral classical. The bass is very powerful and doesn't sound boomy and boxy - and this is the first closed back headphone I have heard that sounds this open. The mid range is smooth and well textured - non sibilant, and the highs are clear and shimmering. Really the best of both worlds of dynamic and membrane drivers.

Technical details: source is Jriver streaming high resolution FLAC (96kHz) or WAV files. I also tried Amazon HD and that sounds very good too. DAC is SMSL Sanskrit 10. Most listening was done on Aksa Silicon Harmony, DCA, and Fiio A5.

Test Setup with other cans and Silicon Harmony amp:
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Closeup of solid walnut wooden earcups and detail of walnut 3.5mm plug and gold jack. The cord includes a microphone and 3.5mm TRRS plug (for use with phone or for telecons) and 1/4in TRS adapter. You could use your own 3.5mm male-male cable if you wanted to - no proprietary connectors here. The cord is very short - great for use with a phone or portable amp, but probably in the studio you could use a longer cord. Easy to do with any longer 3.5mm to 3.5mm male/male headphone cable.
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Here is a detail of the metalwork at the main hinge on the yoke, nice hex cap screws instead of usual Phillips screws, and metal has a satin texture. It feels like cast zinc - tougher and heavier than aluminum:
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Here is detail of the backside of the yoke showing the channel for the wiring to pass through the headband, the telescopic springs, and the yoke. No external cables are visible except the main one that plugs into the left side from the amp:
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Ergonomically, it feels very compact - does not stick out like the HE400i and the headband and yoke are low profile without protruding rods or other hardware like some headphones. The clamping pressure is firm, but can be adjusted somewhat by applying slight pressure on the headband outwards a bit. So far the comfort is fine and it applies enough pressure to seal the outside sound out and the music in. People cannot hear any sound escaping from the headphones when you wear them - cannot tell they are on. Some people have complained that they feel heavy. They are indeed a bit heavier at 417g vs 362g for the HE400i, but because they are compact, and there is a well padded headband and earpads, the weight is not uncomfortable. The quality of the metal work and wood and total absence of any plastic (except maybe the covering of the pleather - which might be real eather, I can't tell) make up for any issues witht the added weight. I like how compact they feel while being worn. The look is understated but exudes quality and has some gold and the solid walnut finish is superb.

So far, these are now my favorite headphones. They have sensitivity of my balanced armature IEM's, the bass of my OB-1's, and the hghs of my HE400i's, but eith more detail. Nothing about them is a negative thus far. I will continue to listen and see how the long term durability is and report back later.
 

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Update on these headphones after taking on a airline flight is that they are very compact and easy to setup and store back in their case. Because they fold so nicely and don’t require a weird 180deg yoke flip that many other cans require to fold, the folding is fast and easy. They also can’t scratch themselves during the folding which I have had happen in other cans when you have metal to metal cup contact if it folded earpad-to-earpad. Having a short fabric covered removable cord also makes folding and storing the cable a snap. The case has a built in mesh compartment for storing the cable. I found out that a small pocket amplifier can be stored in there as well, making for a nice complete portable headphone listening package.

The sound still remains excellent and I am hearing detail I haven’t heard before. One area of detail that was surprising was this: the top crescendos are highly resolved and piercing and modulated within the crescendo (like the slight vibrato of several higher octave piano keys at full strength fortissimo), whereas they were either clipped or compressed and mushed together in the past. This is because the sensitivity is so high that only about 35microwatts is needed for usual sound levels. Thus, plenty of room is left over for peaks.
 
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Hi Pelanj,
They are priced well below what they would cost for the quality and value. Since you know what an AMT-1 sounds like, I’m sure you will appreciate these. The resolution and clarity are superb, but what makes them special is the sensitivity on top of that resolution. Then there is the build quality. There’s nothing to not like or complain about actually.
 
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Almost anything can drive them since 110dB/mW. However, I find zero global feedback SE Class A amps with minimal actives sound best and I have been driving them with my Desktop Class A (DCA) amp. It’s a JFET input MOSFET source follower. All through hole with exception of BF862 or 2SK290, or optional 2SK170.

Here is the amp in use with 422H’s.

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ESS Headphones and packaging note

For those that avoid Amazon or prefer their cash go direct to the mfg. they are the same price direct from ESS.

lousymusician:

Great idea....buy direct. I like to support smaller companies who do a good job, rather than give money to a gigantic corporation that doesn't pay Federal taxes on their billions in profits.

I just received my pair of large Heil drivers yesterday from ESS, and it was the best packaging job I have ever seen, bar none. I'm now looking seriously at these headphones, and am very glad for XRK's review.

And as others point out, Rick at ESS is a very likeable, positive person to speak with too.
 
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I also encourage buying direct if possible. As I was unsure how these headphones would pan out - as the reviews seemed to be mixed because some were negative but earlier 2017 era and later ones seem positive. The Amazon Prime benefits removes the risk of the unknown. But if you can get a no hassle return policy direct, by all means use it.

I have a friend in California who knows Rick at ESS personally. He just goes to the factory to hand pick up the items and he also says that Rick at ESS is very good to work with relative to customer service. Nice to get stuff form a small company and great that their headphones really exceeded expectations from sound quality and build quality. I think that the aesthetics of the design is also excellent. Not just another black plastic faux metal dynamic driver headphone. Truly different technology and superb sensitivity.
 
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ESS

The shipping is a little over 70 USD and then add customs and VAT. I ordered the large AMTs two months ago, once shipped, it took a bit over a week to arrive to my place. I recommend to buy direct, too.

Pelanj: I'm going to order a set based on the in-depth review from XRK. They look great, and the price is right.

I hooked up my Heils today in my vintage speaker, and used the standard 800hz crossover that was in them, and disconnected the horrid horn. It is a huge improvement, and mates up very well with the 100db/watt Alnico woofer. I'm going to play with this combination, and start looking for a woofer that plays lower. I'm super impressed with the Heils so far, even though they are not broken in yet. They image very nicely, and have startling dynamics. Wow. I'm glad I read your other post, because I had no idea these would play as low as they do, even without double stacking.

I wish the lead wires were a bit longer, and thicker/more rugged.