[RiKToR]

I have recently had the pleasure of obtaining a pair of Westone AC20 Musician Monitor’s.  These were recently released and replaced the Westone AC2 product.  Having read the review posted here on Head-FI, I realized that these monitors may have a different sound signature than their predecessor.  So with that in mind I will attempt to review them to the best of my ability.
 
Some background:  I am not necessarily an audiophile.  I am a musician. I have been playing guitar for 17 years and during that time I have picked up Keys, Drums, and Bass.  I am also a vocalist, however, I don’t consider myself the greatest at this and generally stick to BGV.  I have been playing on worship teams for 14 years mostly playing lead guitar.  I have never owned a pair of CIEMs so I have no reference for comparison to other CIEMs.  However, I have been searching high and low for sub $100 head phones that could meet the demands of being a universal IEM for our monitoring systems.  I have used the cheap of the cheap and some bigger names; Koss, Sony, Philips, Ultimate Ears, Shure, and Senheiser (to name a few).  I have mainly have issues with the glue coming apart or the cable going bad, which causes me to replace my headphones often.  I generally have these in my ears most of the time listening to music, audio books, and rehearsals in addition to the stage monitoring.  I am also a sound engineer, I have worked as an engineer for live performances, corporate events, and independent film work.  Nothing big name but enough to say that I know my way around sound tech stuff.  I tend to be budget conscious so I have never used the “big gun” toys unless they came on a rental.  My own gear is pretty conservative.  I just figured I would let you know a little more about me since I am new to Head-FI.
 
Disclosure:  Though Westone did not comp a pair of AC20s to me an authorized audiologist dealer offered me (and the members of my band) any Westone CIEMs  at cost plus free impressions.  My church offered to pick up the cost of the AC20 and I could upgrade at my own expense.  The dealer is a member of church and has seen too many times where we pull out our IEMs because we can’t hear and he was worried about our long term hearing. You might feel that this may or may not sway my impressions; so full disclosure.
 
 
The packaging:  The AC20s actually came in the AC2 packaging (this was due to ordering them prior to the announcement during CES).  However, the Acrylics are labeled with AC20 and have the MMCX cable connector.   The packaging also contained a generic manual for all of the Westone CIEM offerings.  As usual a case was provided (the orange Monitor Vault Pelican Case) and ear wax loop as well as a black cleaning cloth.  Also, an orange Dunlop Tortex guitar pick with the Westone W was provided (oddly the same picks I buy, so a bonus for me!).  I may spring for a larger monitor vault later on as the orange monitor box is a little small. 
 
Delivery Time:  Impressions we done on January 3^rd and sent out that day.  They were delivered to my audiologist on January 14^th.  I am thinking they took about 5 business days to make.
 
The Monitors: I opted for clear Acrylics, I checked with the rest of my team to see what colors they were getting.  That way they would not get mixed up with theirs.  They do come in blue, gray, black and red.  I probably would have stuck to clear anyway unless, flesh tone was an option.  The monitors appeared to be crafted well.  You can tell where the seam is from the mold to the faceplate and there is a minor cosmetic blemish near the side of one of the bores.  These are cosmetic but I constantly think there is ear wax in that bore only to find none.  Since I am on the subject of bores, these are not dual bore as Westone’s press release indicated.  I have emailed Westone (great customer services) when the press release came out for clarification.  They indicated it was a typo.  The dual bore, flex canals, and 3+ armatures are reserved for the ES series.  The monitors are labeled with a large orange Westone “W” and the AC20 designation underneath it.  The serial numbers are printed in black with L and R designating the side.  This is preference of mine due to varying lighting on stage washing out reds.  Everything is polished to a high sheen except for the logo which has a textured etched feel.  As I don’t have a reference point CIEMs , I don’t know if that is normal for graphics. 
 
Fit:  My audiologist did not provide me a bite block. However, my friend had told me about his two impression experiences so I followed his advice.  I opened my mouth simulate smiling on a bite block and occasionally opened wider while the impression material was setting.  My audiologist inspected both impressions and we ended up redoing the left side due to a weird gap.  I was a little concerned with not having the bite block but the fit is actually working well.  I have chewed food, sang along with songs that I was listening to but I cannot get the seal to break.  The occlusion effect is also reduced quite a bit from my other headphones when I sing.  This helps me tremendously.  These block out quite a bit of noise.  I can say that they are very similar to some firearm earplugs that I have.  Those were rated up to 32db reduction I believe.  At the very least I can buy the 25db reduction that Westone has advertised.  They are extremely comfortable.  My ears must be slightly different than most because I do not have to rotate these to get them in my ear.  They are very smooth and I have not had to use the provided Otoease.  The cable is pretty thin and light weight.  They have a little bit of the memory wire feel but there is not actual wire.  I bought a pair of Shure replacement wires that have a very dominate memory wire; they work as well but I like the stock EPIC cable.  I have not had the opportunity to use these as monitors yet so I may have more to add later on the subject of fit.  For now, they seem good and I will probably not send them back for a refit. 
 
Sound:  I will do my best to articulate what I am hearing on this subjective topic.  My main device for listening is iPhone 4s and an M-Audio Profire 610 on my recording rig.  I have also used these directly out of a headphone out on a Dell computer (at work) and my Alesis DM10 digital drum kit. 
My initial impression is that these sound pretty flat, this is contrary to their predecessor; see the AC2 review on Head-Fi.  I am revising this statement in that they are not entirely flat, there a few things that are “colored” and I think it has to do with their purpose as a monitor for musicians.  Firstly the vocals around 2kHZ seem to have an boosted presence.  A 2-3db reduction in the 2KHZ range can balance the vocals back into the mix.  I think this is there to clear up some of the mud in vocals that are in a live setting.  When a vocalist is close to the microphone their voice gets a little low mid mud but this preferable then cranking the gain and getting drum bleed in the vocal mics.  Also, vocal cues are pretty important for band members in the worship world because the leader can call an audible vocally and we can alter the song structure.    This boost would allow us to hear the vocals pretty clearly in this environment. 
 
Highs, are smooth but detailed.  I don’t really know how else to describe it.  I am referring mostly to cymbals on drums.  Washy cymbals seem to be clean and not piercing.  I can definitely hear the highs being rolled off a little.  I find myself wanting to bring up 8khz a little to get the timing of a high-hat or a ride.  This seems to be contrary to what I would want live as I would like to hear the timing.  As I have yet to use these live I will reserve judgment until then.  When you’re dealing with cymbal hits of crashes and rides being played like a crash the “washiness” of the cymbals seem to blend perfectly into the music.  It also makes the samples on my digital drum kit sound pretty good.  The balanced armature does really welly at cymbal articulation.  I don’t sense any harshness that I got a lot of in my other headphones.  There were several live tracks that I listened to that I remember cringing at points of crowd cheering.  The AC20 doesn’t cause me to cringe and I feel that I can here individuals in the crowd better.  The detail that I am hearing is impressive and I find myself enjoying this quite a bit.  I have a digital drum kit (Alesis DM10) and I have played with the AC20 direct out of the headphone plug.  I won’t say that it improved the samples but the cymbals did feel like they were improved compared to what I am used to.  They are normally harsh and any drummer will tell you the cymbals on digital kits are awful.  I liked how the AC20s improved the smoothness of the cymbals.  High frequency fatigue would definitely cause me to put my sticks down earlier. 
 
Lows: I am a bass head.  My normal stage monitor mix is Kick, Snare and Bass guitar with my vocals and my guitar.  I like to feel the music on the low end, most musicians do.  I have tried not adding any color to the bass end of the AC20 to get a proper idea of what driver is naturally producing.  I have listened to many different types of music (techno, rock, blues, symphony) to get some feeling as to the bass response.  I would describe it as capable of producing hard, tight hits in the case of drums while still producing some ambient smooth bass in the case of synths that hit tend to provide that fill the room sub-bass that you feel more than hear.  For me personally, it is a little less present then I would like but it is truly there in the mix; you can clearly hear it.  For what it’s worth it seems that it is balanced with the rest of range.  Personally, I could be perfectly happy listening to music without color the bass and at some points I was thinking that I had adjusted the eq because the sound was so full only to find that I had not done anything.  If the producer/mixer wanted you to hear it, it was there without any additional eq. 
 
Mids: Everything seems to sit pretty balanced in the mid ranges.  I cannot pick out a frequency that is dominant until I reach the 2khz of the vocals and that seems like it’s a very narrow band boost.  What I will say is that everything is clearly defined.  I typically listen to music and like to focus on certain instruments or groups of instruments.  I examine it at the level in which I would want to be able to duplicate the playing perfectly.  The mids seem to possess clean instrument separation which allows me not to strain to focus on a specific part.  The low mids balanced with the higher frequency mids really well which adds to the articulation of different instruments.  I can pick out what string on a guitar is used to play the note in addition to the note itself.  It could be my musical senses maturing a bit but I can definitely sense some higher levels of definition in all areas of the audible spectrum.
 
Final notes:  I love these CIEMs.  I will admit, I have wanted a pair for 8 years so I may be just excited in general.  I am kicking myself for not getting these sooner.  Since the acrylics make for a studier headphone my only concern is the cable.  I bought a Shure replacement for $30 off of amazon to have a back-up cable.  I would easily feel comfortable mixing sound with these headphones.  I feel that the 2khz boost would have to be accounted for but everything else would be very balanced.  I am very happy with what Westone has done with this product and I am perfectly content.  I look at the ES series and think, these AC20 are pretty damn good; why would I buy a pair of those.  I think the flex canal would be my only reason.  The AC20, right of the box, sound great if you’re fit is good.  If you like to boost certain ranges, bass head, the AC20 does respond well to eq.  I recommend listening to them without EQ for a bit and decide what you want from there.  A little eq also goes a long way.  If you want a boost or a cut, you really are talking about 2-5db tops.  I also have found that I have been listening at way lower volumes then I used to.  My normal volume range was 70% on my iPhone but these are within the first 30% I find a comfortable sound level.  It’s partly the noise isolation but also just that I get a full sound earlier on the volume slider. 
 
I will provide some more thoughts (and photos) once I give them a couple of weekends of live use.  At this point I am truly happy with this product.  Granted, I don’t use headphone amplifiers for them or any audiophile gear but they sound great to me and they will probably save my hearing.  Personally, I am enjoying every moment.    

 

[RiKToR]

Adding some photos.  
 
First is the entire package (still in the AC2 box since they had just announced the AC20 when I ordered them)

 
Close up of the earpieces and logos.

 

 
Update, I have played three live performances with the AC20s and I was, luckily, in three different disciplines during those performances.  So I fee I can offer some nuances about them.
 
For reference, all of my live performances monitor feeds come out of a Mackie Onyx 32x8 Mixer into an Aviom A-Net hub (AN-16/i). The hub runs to our rack system, about 100 ft, to our rack module (A-16D Pro) then to our individual A-16II individual monitor systems.  The entire setup should be pre-fader and pre-eq.  The only thing that is before the Aviom output is the initial input gainstage on the Onyx.  The system allows me to control up to 16 channels of my personal mix with volume/pan controls.  It also has High and Low EQ controls that provide a shelf style +/- 12dB to 9kHZ and 160hz to the master out, respectively.
 
Guitar:  My first performance I was playing my stratocaster, I was not doing any vocals.  I was able to spend alot more time creating a mix in my Aviom.  I boosted about 3dB on the Low end and 4-5 on the highs.  This was to satisfy my bass head nature while countering the previously mentioned roll-off for cymbals that keep timing; rides, high-hats.  I was actually suprised that I didn't have to pan items as much as I had done previously.  I used to have to hard pan everything to the left or right to be able to discern the individual instruments but with the AC20s I was able to easily pick certain instruments out of the mix without having to pan much at all.  Some musicians only want to listen to certain instruments but I always want to listen to the full performance.  I had two electric guitars, a fully mic'd drum kit, an electric bass and two vocalist. Everything was distinctly heard and full bodied and the AC20s were extremely comfortable.  I did not feel them break seal at all.  There was a feeling of isolation though, which is expected with any CIEM.  Once the music begins you lose nearly all ambient noise which leads to separation from the crowd.  Some may like this but I am not a fan as most musicians are.  This can be defeated by adding an ambient mic, which we did for the second performance of that day.  It helped a little but the setup was rushed.  The CIEMs peformed as mentioned before, my guitar sounded a little darker because of the high end roll off that the AC20s characterized.  I did find some difficulty with finding the high-hats and for monitors aimed at musicians I was surprised that such an important instrument was rolled off.  I compensated abit but the shelfing that the Aviom has was 1Khz too high.  I feel this partly the setup we have on our drums and part the AC20s.  More on this later.  This was still way better then my previous universal experiences by leaps and bounds.
 
Vocals:  This performance I lead vocally.  I was still playing electric guitar but I honestly turned that volume down to focus on the vocals more.  As personal note, I find that I mentally have to either focus on vocals or guitar and I cannot due both.  This leads to me either turning one down or the other.  There have been times I have not worn monitors while leading vocally so I could hear the front of house performance; not good for the ears though.  The separation from the audience was more noticeable when your leading vocally.  This would be a time that you would want to have ambient mics.  Vocally, I was able to clearly hear myself; nuances, subtleties, and pitch which had been quite difficult before.  I usually have at least one monitor out of my ear for vocals, but this time I was happy to leave them both in.  I could clearly hear my self with the rest of the mix as well.  Usually this a deeply muddy experience where you pick one or the other.  I found that this "mud" was reduced by the clearer articulation provided by the AC20s and the reduced occlusion effect (where your vocals echo in you ear canal due to the headphone obstruction).  You can clearly here full range sound with your vocals but you are able to push your vocals to the front clearly so you can have a full feedback of the vocals you are projecting.  If you are a vocalist and you want inexpensive CIEMs, this is the headset your looking for.  On a side note: the issues with high/ride occur here as wells so some EQ compensation maybe required.  We modified our mic setups which was actually detrimental to the cymbals in the monitors.  I think this was more an issue with our setup rather than the AC20.  That being said, if you are a singer who has problem hearing time, you may need to boost these frequencies.  We have a singer who is like this and he has gotten worse with the AC20s.  I am going to work with him to see if we can fix this.
 
Bass:  My last performance I was sporting bass.  The live bass sound was smooth with little high end for the instrument.  Again probably due to the roll off.  Also, the instrument had flat wound strings which takes what little twang you get out of Bass strings and throws it out of the window.  I bring up this experience only to mention that you can get the Bass response that you want out of the AC20s, withing reason.  If you crank the Bass, ie 160hz at +6dB well then its going to get muddy.  It was pretty difficult to find the right balance of bass with drums.  Again, we had changed our mic setup and it was still detrimental to the performances so I think we will need to fix that.  If we resolve this during a follow up performance then I will weigh in.  If you have the money for AC20s at nothing higher end then I would say that it is definately worth the investment.  If you can save for triple driver or five driver ES then I would lean toward that if I played Bass all the time.  
 
All in all the AC20 CIEMs are worth the money.  They are the solution for my longtime issue (11 years) of finding the right headphones for monitoring.  I personally don't feel the need to jump to the ES line but I am certainly curious.  If I were a Bass/Drummer then it may be worth it to save the money for a triple or more driver system.  

 

[EpicAnthony]

Very informative and well constructed review. +1

 

[project86]

Thanks for taking the time to write up your thoughts! It was a good read, and will be even better with pics. 
 
Sounds like Westone has improved this design for the better. Not that the AC2 was bad per se, but it was definitely more specific.... the AC20 sounds like it would be more versatile. 

 

[Jedaite]

don't worry about the cable. It was last for a very ling time. In fact, mine went through some very harsh pulling dozens if times and it still works.

 

[RiKToR]

I am hard on my headphones so I figured an extra cable that I would never need was at least good practice for when I play out. 

 

[RiKToR]

Added photo to the post.

 

[project86]

Looking good! That cable is different from the older style I got with my AC2, ES5, and ES3x back in the day.

 

[GeneraI]

How much do these cost?

 

[RiKToR]

I believe they are going to be retailing for $400 - $480.  Somewhere in that range.  You would want to check with a local dealer.

 

[KHill]

I finally received my AC20's after delay from Westone.  Haven't had much time to listen to them yet, but plan on doing so this weekend.  
 

 

[project86]

Nice color scheme. Simple, but clean and attractive. Hope you enjoy them.

 

[KHill]

Nice color scheme. Simple, but clean and attractive. Hope you enjoy them.

Thanks!  I really like how the color scheme came out.
 
Just to add some points to Riktor's review.
 
My fit is top notch!  Westone did my impressions at CES with a bite block.  Whatever I do, I cannot get the seal to break.  They are also super comfortable. I've worn them for over an hour straight and almost forgot they were in my ears.
 
I also agree that they are fairly flat sounding, but the vocals are boosted just a touch.  Which is really great for me, since I do use these on the worship team at church with vocals.  The highs are rolled off slightly, not as much as the UM2, but still rolled off.  The highs are detailed though.  I also have not noticed any sibilance in the highs, which always bothered me with the UM2's and W4R's.  As far as bass goes, Riktor is dead on. I don't feel they are as bloated bass wise as the UM2's.  Mids seem to be the typical Westone house sound, which I love!  
 
Overall, I absolutely love these IEM's.  They are fantastic for live performances, way better than the UM2 ever was for me; at least for vocals.  For casual listening, they are very good, almost fun (not as fun as UM2) and not fatiguing.  Although, when I'm in a detailed frame of mind, I will use my W4R's.  At the present time, I also don't see any reason to step up to the ES line.  I couldn't be happier with them!