[REVIEW] Heir Audio 8.A: 8-Driver, 4-Way Crossover Custom Fit In-Ear Monitors

Synopsis: The Heir Audio 8.A is the flagship custom-fit in-ear monitor (ciem) from Dr. John Moulton at Heir Audio. It's tuned for a supremely warm, rich sound. This very well designed ciem manages to combine this lush sound with excellent precision and clarity. The bass is very well extended into the sub-bass with a lot of well-controlled mid-bass for a fun sound. The midrange is quite warm with a thick resonance to notes, while still maintaining clarity. The treble is very precise and non-fatiguing. It avoids sibilance while shining beautifully and has excellent extension. Everything comes together nicely for an organic, engaging sound. The Heir Audio 8.A is very well crafted. It both looks and sounds great.

Introduction: Dr. John Moulton is an audiologist with a love of making beautifully crafted custom in-ear monitors. He's displayed his work on head-fi and discussed his philosophy on engineering ciems there as well. These discussions and images drew a lot of attention and many people (including me) wrote him about the possibility of making ciems for sale to audiophiles. He's made that happen with Heir Audio. You can see the work he has done on his facebook page (click) or on the Heir Audio website (click).

I have the dynamic driver ciem Future Sonics MG6Pro Ear Monitor, which I'm very happy with. I was curious about what a top-tier balanced armature based ciem would sound like. You can read about the different types of drivers (the transducers which produce the sound in an earphone) here (click). However, I was disappointed by one of the options out there when I had a chance to listen. Dr. Moulton's superior technical expertise combined with his artistic craftsmanship made him seem like the perfect person to work with. I knew I wanted the best he had to offer--his flagship ciem, the 8.A.

Disclaimer: I think it’s important to be open and up-front about the way one has received the product reviewed, so everyone can be clear about any underlying motives which might bias the review. Right now, there is a promotional price of $1099 for the 8.A which will go up to $1299 in the future. I received a discount from John for being one of the first to purchase an 8.A in exchange for losing a year off the warranty and losing the excellent resale and remold feature, which I'll talk about below. I also couldn't choose the appearance of the custom, which is a big concession. In addition, I agreed to contribute to the Heir Audio appreciation thread here on head-fi. So much for that. My review will be my honest take on the 8.A and my usual approach is that a good review gives you a well-rounded take so you have reasons not to choose it as well as reason you might choose to buy it for yourself.

Customer Service: This is a huge part of a custom fit in-ear monitor as each one is molded to your unique set of ears. Bad customer service can sour the whole experience and several big name ciem companies have fallen down on this. On the other hand, excellent customer service can be a wonderful thing, becoming a relationship that lasts and greatly adds to the value of your purchase as you are truly in good hands. Dr. Moulton is off to a great start, I'd say, in terms of good intentions and responsiveness. I'll be frank: I am a difficult customer. I ask a lot of questions, I complain and I generally am a pain in the rear end. John handled my questions excellently and he was very responsive. I also spoke with another of his colleagues and she was great as well.

However, I will say that that the folks at Heir Audio are new at this and sometimes it shows a bit. Things didn't go as smoothly as I would like when it came to shipping to and from China. I spent extra money to use FedEx and I'm glad I did because they were on top of things when Chinese Customs decided to throw a wrench in the works. Heir Audio dropped the ball a bit and weren't as clear and informed as they should have been, forgetting to give me a phone number which apparently Chinese Customs needed, things like that which will get much better quickly with a little more experience. I want to emphasize that they did their best to take care of things--the key point is that they care. Overall, it was a very good customer service experience and I think it will be even better for people who follow after me.

One other thing: Apparently I have small ears and 8 drivers need a fair bit of space. John worked with me and my customs stick out a few extra mm to accommodate the extra space needed. That is an example of excellent customer service.

Warranty and Owner Transfer Service: The warranty is 2-years, which is very good, but it's the owner transfer service which is the exciting part. The problem people sometimes have with custom iems is that if you don't like what you've bought, it's hard to sell them. The next person has to have them remolded to fit their ear, which means going to an audiologist for earmolds and then having someone remold the ciems--and there's no guaranty that the remolded customs will sound like the originals if done by a third party! Here's where John's awesome service comes in. With Heir Audio (and the warranty card--hold onto that!) you can transfer ownership to another person. John will take the new owner's earmolds and he himself will remold the custom iems, testing and tuning it himself for perfect sound--AND he gives the new person a 1-year warranty. You can read about it here (click). It's excellent and should greatly increase the resale value of the ciems. Not that you'll want to sell them if you're smart about the knowing the sound signature you want. The info below should give you what you need to make a good decision if you take the time to understand the sound you want.

The 8.A: The 8.A has 8 balanced armature drivers. It might be useful to contrast the 8.A's set up with that of another 8-driver custom, the Jh16. The Jh16 uses two double-driver armatures for the bass--for a total of four. These two doubles are called the DTEC and each of the four TEC drivers is rather small. Dr. Moulton uses a much larger driver for the bass, called a CI. This driver has a much larger frequency range--and John uses TWO of these larger drivers. In addition, he uses a unique damper to give this extra bass capability and range an extra measure of control. For the mids and treble, the JH16 uses a Sonion brand double armature for the mids and a double armature DWFK for the treble, giving a total of 8. Dr. Moulton, on the other hand, uses a double armature TWFK for the midrange, another TWFK for the treble and yet another TWFK to handle the upper treble--giving a total of 8 drivers well distributed to handle each part of the frequency range with power and perfect control. There are three sound tubes for bass, midrange and treble, all perfectly done.

These drivers, acoustic filters and crossovers (a 4-way design) are housed in a typical closed acrylic shell. What is not so typical is the craftsmanship with which John makes them.

Here are mine, made of wood and horn, a very classy and stylish look.

An in-ear view, the picture doesn't do the organic quality of the horn justice.

(my ear is for display purposes only and is not included with purchase of the 8.A)

Craftsmanship and Build Quality: Outstanding. There's very little more to say, these are simply very well made and done with an industry leading level of skill and care.

Isolation: Good, these will have the same isolation as any other closed-shell acrylic ciems.

Sound: This is a fun sound with extra mid-bass and a quite warm midrange done with excellent control. The overall sound is quite warm, lush and smooth with excellent extension above and below. There is no brightness or harshness to speak of, although the treble can still sing appropriately to the recording. While John has told me he has tuned for a mild V-shape which dips a bit at about 500hz (which is a common tuning for a lot of headphones) for a fun sound free from any muddiness, I don't hear a recessed or de-emphasized midrange, on the contrary, the warmth of the presentation gives the mid-range instruments and voices a richness with no loss of clarity that many people will love. The combination of a very lush sound which still has excellent detail (without putting it at the expense of musicality) is perhaps the keynote of the 8.A.

One aspect to the sound I'd like to mention is the coherency. This is the ability of an earphone to depict all the instruments and voices in a piece of music as each playing one together as part of greater whole. The 8.A does this well, depicting good instrument separation while providing a holistic sound. When done poorly, such as the Jh16, it can sound as though each instrument was artificially mixed in separately, giving a fake hyper-separation to the sound, which some people may prefer if they don't like how live music sounds. The 8.A avoids this and a rich cohesive sound which give everything its proper place and ties it all together nicely. Complex, fast music is handled effortlessly with great smoothness by the 8.A.

The sense of a space in a recording, the soundstage, is good for a closed-shell BA-based ciem. I would say that the 8.A does very well in comparison with similar closed acrylic shell ciems.

Treble: The 8.A is the ultimate in a non-fatiguing, very well controlled treble. It's very, very smooth and definitely not like those hyper-bright and glaring treble presentations found in some earphones. Some people might want a treble that has an exciting "bite" to it or a lot of energy, you won't find unnatural brightness here. What you will find is a treble that is very well balanced, has a nice presence and sparkles and sings appropriately in a piece of music with superior extension and very good detail. You could listen for hours and never grow tired of the way soprano voices, violins, etc. are portrayed. I will say that the TWFK driver and its relatives don't do perfectly with the realistic reproduction of some subtle resonances in instruments and voices (timbre). Cymbals are a particular issue, as they can be hard to reproduce accurately for many headphones. The Jh16 was poor at this, and the 8.A has a related driver with the same issue. However, the 8.A does better--perhaps due to Dr. Moulton's skill at tuning and the better coherency of the 8.A. On the other hand, voices, flutes and violins sound great. I'd say it's a minor weak area, which you may not notice (and it's probably on par with many top-tier BA based ciems), but those who want the very best timbre may look elsewhere.

Midrange: If you like a thick, quite warm midrange that you can just wallow in, this is the earphone for you. This is a tuning that gives strings, guitars and voices that extra helping of richness to make them even more euphonic. The achievement here is that the 8.A manages this while still providing excellent detail and clarity. The added warmth is fun but it's something that isn't for everyone. People may want things a little more natural for the sound of pianos, for example. In particular, those who want a dryly detailed colder presentation won't care for the warmth, but many people crave a lush sound and it's truly well done on the 8.A.

Bass:  Oh yes, the bass. There is a lot of well-controlled mid-bass here, ready to go. There is a lot of sub-bass here as well as the 8.A has excellent bass extension. Here's where those two large bass drivers and their special acoustic filter really are glorious. There is great detail and color in the bass of the 8.A, it is simply superb. You really have to hear it. Bass-heads will love it and audiophiles who don't mind their bass north of neutral but still very well controlled will love it as well.

Music Genres: The 8.A rocks with, well, rock. Some may want more treble energy, but the 8.A's treble handles the strum and thrash of music with such fun and smoothness that I think it works well. Electronica and trance are immersive and the 8.A gives a greatly textured sound that still comes together for the right atmosphere. Dupstep has met its match with the great sub-bass. Classical symphonies are done well as the warm and bass come with a degree of control and balance and detail which works to bring out the feeling in the music, although recordings that already warm may be quite a few degrees north of neutral with the 8.A. Jazz, solo instruments and string quartets often do very well with the warmth accentuating their resonance and a treble that sings. I would say archival recordings tend to sound phenomenal with the 8.A. Old Miles Davis recordings have met their perfect earphone. A less warm earphone with a bit more treble energy can sound a little more naturally lively with some of these genres, but the way the 8.A's smoothly euphonic tuning, detail and dynamic, powerful yet controlled sound can be compelling with just about everything.

In Conclusion: The Heir Audio 8.A has a beautiful warm, rich sound that compromises nothing in terms of detail and clarity. The warmth and bass definitely have a perfectly controlled something extra added to give music more, while the treble is a marvel of non-fatiguing, smoothly singing extension to match. It all comes together very nicely and it's a sound that will suit many people, but it's not for everyone. Some will want a less warm or lush presentation, or a brighter treble. That's okay, John has other ciems with different tuning! No seriously, Heir Audio has a full line of customs. For those who want what the 8.A offers, though, you won't find anything more capable and the 8.A makes some of the competition look outdated. For incredible craftsmanship, great customer service and a lush sound that just gives more and more enjoyment with each hour, look no further than the 8.A.

Brief Comparisons of the Heir Audio 8.A with Other Custom In-Ear Monitors

1. JH16 (demo)

The Jh16 and the 8.A make a good comparison because they are both 8-driver ciems. However, they are set up very differently, with the Jh16 having four small bass drivers, two midrange drivers and two treble in a three-way crossover system, while the 8.A uses two large bass drivers, two midrange, two treble and two high-treble drivers with a four-way crossover system. There are a number of ways the sound differs as well.

Overall:  One of the main differences between the customs is the way they present music. The Jh16 has an emphasis on detail and details in music are very clear, but it does so at the expense of a cohesive, natural sound. When listening to a symphony, each instrument tends to sound as though it had been artificially mixed in. I've noticed that Jh16 owners will go for cable upgrades, etc. with the express purpose of obtaining a more cohesive sound from them. The 8.A, by contrast, does much better in terms of giving a holistic take on music where all the voices and instruments sound as though they are playing together, each in their own part of the stage, but on the same stage at the same time. There is very good detail, but the musicality is not sacrificed. The 8.A is smoother overall, the Jh16 has more of an edge to it. The soundstage for the Jh16 is large, but sometimes doesn't quite fit the recording. It's a large regardless. The 8.A can be spacious, but is intimate when the recording is intimate, like for a recording in a small jazz club.

Treble: At moderate listening levels, the Jh16 had a nice, slightly dark treble. With higher volumes (not recommended for your ears), some harshness came out, but I try not to listen loud often. People have reported more harshness in the treble than I heard, this may be due to the fact I used a demo with foam tips which can take the edge off treble sibilance. The 8.A is smoother in the treble and never shows harshness while still giving a good singing sparkle to its treble. One of the weaknesses of the Jh16 was that it didn't handle the timbre of cymbals as well as other top-tier ciems. The 8.A has this same issue, but due to the better coherency and greater richness of sound, it sounds better--not perfect, but better. This is something that some people won't notice with the 8.A, but obviously I was looking for it.

Midrange: This is where the difference between a musical, cohesive sound with very good separation and detail (the 8.A) versus an artificially separated and detail first sound (the Jh16) is most noticeable. The 8.A has more warmth and richness to its midrange, a difference in sound signature.

Bass: They both have very good bass, I don't think anyone will be disappointed. The 8.A has better extension into sub-bass and is smoother, more effortless and better textured.

I said on another thread that there's no reason to buy a Jh16 now that the 8.A is here. That's true to some degree as the 8.A beats the Jh16 at its own game, pretty much across the board, at least for audiophiles. However, I think what are weaknesses for me and will be for most people, will either be not noticed as few people listen to several top-tier custom iems or even be appealing to some for use as a stage monitor.

2. UE IERM (demo)

The In-Ear Reference Monitor is a 3 BA driver, 3-way crossover monitor tuned for a flat sound that is emphasizes clarity without sacrificing musicality. It aims to be true to the recording, and I would say it succeeds in large part.

Overall: The IERM and the 8.A are tuned quite differently and they complement each other. The IERM is much flatter, much less warm, thinner. It sounds a bit on the flat side of natural. It's quite good but can sound a bit dry and not so exciting. The 8.A, of course, is a lot warmer, thicker of note. It is smoother--it turns out that the 8.A is actually pretty darn smooth in comparison to other ciems in its flagship class. The IERM may be a bit more intimate in terms of soundstage. The IERM generally does very well with instrumental and vocal timbre, better than the 8.A, which does fairly well (this is a comparison between very good ciems).

Treble: The IERM has a nice treble. The signature is a little different as it has more energy than the 8.A. The 8.A will be more non-fatiguing and will still sparkle. The IERM also has very good timbre. However, there's a rough spot in the treble, whereas the 8.A is smooth all along the range.

Midrange: Guess which one is a lot warmer and richer? Yes, the 8.A really sounds different than the thinner, flatter, cooler mid of the IERM. The IERM brings out the clarity in a recording while still sounding natural and cohesive. The 8.A has as good detail and clarity, but it's part of the warmer, thicker presentation, so it's a question of emphasis, not of capability.

Bass: The IERM actually has a very nice bass quality with a lot of control. It's definitely subdued and lacks bass extension in comparison to the 8.A, which is simply more bass capable with very good control. The 8.A has more quantity in mid and sub-bass without the roll-off at the bottom which the IERM has.

I like the IERM, it can be beautifully clear and true to the recording, but it will definitely be a bit dull for some. The 8.A is a very different, more fun sound. In some ways, it's better technically but I would say people should look more at which sound signature they would like to hear.

3. The Future Sonics MG6Pro Ear Monitor

The MG6Pro is a professional stage monitor with a 13mm dynamic driver. It's crossover-free and has an adjustable low-frequency vent to allow adjustment of the bass (particularly sub-bass)--this gives a special quality to the bass. It's remarkable for its superior timbre, more headphone-like spacious sound, natural, yet lively sound signature.

Overall: These two ciems have different sound signatures, with the MG6Pro being just slightly warm, yet very natural and accurate. The 8.A is definitely warmer and adds extra fullness to notes while the MG6Pro aims at more true to the note presentation. They are both very, very smooth. The MG6Pro is the king of realistic, beautiful timbre--the realistic reproduction of subtle resonances in instruments and voices. It is slightly better than the 8.A in this, in direct comparison, but the 8.A is no slouch. The vented MG6Pro has a more out-of-the-head spacious, headphone-like quality to its soundstage--it's like a new dimension opens up when compared to closed-shell customs. Isolation is slightly better on the 8.A when the MG6Pro uses open vents, however, the MG6Pro still has good isolation (a bit more wind noise, but close, as long as the fit is good). They are both quite resolving as well.

Treble: The MG6Pro and the 8.A are both non-fatiguing in their treble. Neither is harsh or overly bright--they are both very smooth with a treble that can sing appropriately. However, the MG6Pro has more treble energy and sparkle, while the 8.A achieves for the ultimate in non-fatiguing sound while still having the ability to be prominent and soar with violins and soprano voices. It's beautiful and so well controlled, but the MG6Pro is more lively while still being very smooth. The timbre is better on the MG6Pro and things like cymbals will sound more real.

Midrange: The 8.A is warmer and thicker in the mids, aiming for a north of neutral richness that adds something extra to music. It's a very likeable lush, rich warm signature that still has clarity and detail. The MG6Pro has a more delicate sound in the mids, by contrast. It's slightly warm, but more natural and neutral, yet lively sounding. A solo piano, for example, sings with a more sweetly real note via the MG6Pro--it is better in terms of timbre. Those who want to wallow in their piano, strings, guitar, etc. and love that extra warmth will want the 8.A, those who want a more natural, yet lively take will want the MG6Pro, it's a matter of choice.

Bass: The 8.A has a fanstatic bass with a lot of bass quantity. There's plenty of mid-bass and very good sub-bass as well, all very well controlled and ready to go. It's an excellent bass with an extra helping of quantity and all the detail and control you could ask for. The MG6Pro, of course, also has fantastic bass with excellent control, and texture. The MG6Pro has adjustible sub-bass with incredible extension (slightly better than the 8.A) and it has less mid-bass than the 8.A for a more natural sound. the 8.A will have more mid-bass and mid-bass punch, while conceding sub-bass to the MG6Pro. Of course, the bass on the supremely bass capable 8.A is lacking that moving-air quality of bass feeling that the vented MG6Pro has. And if you want more or less bass, the MG6Pro gives you choices. That said, they are both very, very good.

They are both very, very good, with complementing sound signatures. I would say look at what both have to offer, know what you are looking for and you'll be very happy with one of these.

Quote:

Originally Posted by ZARIM 

Hi Kunlun, Thanks for the excelent review of these beauties and they looks superb. Iam looking forward to see your brief comparison of these against others CIEMs. BTW how is imaging and soundstage(width, depth, height) on these?.

Hi Zarim, thanks. I'd say a lot of cues for imaging and soundstage come from the recording itself, but that the tuning of the ciem can certainly make a difference. The 8.A has very good imaging and a soundstage that has good spaciousness in all dimensions for a closed-shell acrylic custom (which will usually sound intimate compared to an open headphone or vented shell ciem such as the MG6Pro). Listening to the Gorillaz Plastic Beach album, which was well produced, some of the echo effects on various tracks give a good sense of space. The track Jet Pirate starts with an effect of a sound bouncing up and down, left and right as it comes toward you and the 8.A does a nice job with it. It doesn't sound as though its been tuned for an artificially large soundstage (which is faux large no matter the recording), but sounds true to the recording.

Quote:

Originally Posted by underhysteria 

Well i hope someday you could you compare this with the UM Miracle. I like the miracle's spacious sound with it's extended highs but it's overall sound sig is simply too dry for my taste. Hopefully the 8.As does justice

You're not the only one who felt that way about the UM Miracle, I've spoken to some other people who didn't care for the Miracle for the same reason--not that there's a problem with it, just a case of a sound signature not being right for the person.

Hopefully, I've given enough info about the 8.A's sound that you can decide if it's right for you. I will say that it's a sound that starts great and just grows on you as time goes on.
 

Quote:

Originally Posted by Anaxilus 

Nice review!  I have to say, many of your comments reflect a similar signature to the ES5.  That's a very good thing IMO.

Thanks. That's very interesting about the ES5. It's a nice signature. I think they have the same bass driver (just with the 8.A having two of them), not that drivers are the only element.

Quote:

Originally Posted by Anathallo 

Email John and he'll let you know about the treble of each custom of his line. I remember him saying at least one of his customs has a treble similar to that of the TF10, for example.

Brief comparisons are up in the 2nd post in the thread.