ACS T2: A Thorough Review
Introduction
Hi there! Thanks for stopping by. In the next few sections, I will attempt to provide in as much detail as possible information regarding the Advanced Communications Solutions T2 custom-moulded IEM. Unfortunately, a lot of words were required so I recommend you grab a glass of wine/fruit juice, put on your favourite tunes, sit back in your comfy chair and hang on tight as this will be a long but
hopefully fruitful ride! You have been warned:evil: By the end of this journey, I hope that you will have a greater understanding of this largely unknown but incredible-sounding product.
Enjoy!
-Jonathan
I've only heard of Ultimate Ears, Westone and Sensaphonics, who are ACS?
I gather that most of you have never heard of the company Advanced Communications Solutions. They are essentially a UK-based company specialised in providing professionals with custom hearing protection and monitoring equipment. Their clients include Pink Floyd, U2, The Darkness, BBC Symphony Orchestra, etc. Andy Shiach is the Managing Director and in 1995, ACS were the first company to offer silicone-moulded IEMs. Apparently, it was ACS who provided the initial training to Sensaphonics to manufacture IEMs in silicone. As a result the ACS T2 are very similar to the Sensaphonics ProPhonic 2X-S apart from a few distinct differences:
- The T2 are made from Shore hardness 40 Bioplast silicone while the 2X-S uses Shore hardness 60 Biopore silicone. The higher the Shore value, the harder the material is. I have also been told that the softer silicone lends to a smoother overall sound.
- Compared to the 2X-S, the T2 has an improved 'brighter' high frequency driver (ED9689, also used in the Etymotic ER4 series) and softer cable.
Initially, the T2 was offered in two variants, the T2i & T2Pro. The latter was only available in transparent silicone and had the "over-the-ear" cable configuration while the former was offered the option of a straight down cable configuration (ie a downward-facing cable exit point). Also, there were two different cables that customers could choose from, the teflon-sheathed cable and the normal flexible one. According to Andy, "the flexible cable is more comfortable and looks much better". The teflon-sheathed cable is, however, more durable, aimed at professionals who need the extra durability and incorporates 'the love it or hate it' memory wire. Because of all the confusion the two models caused, Andy has farily recently (October 06?) amalgamated the two models and what is left is the T2. The same options are available along with the custom cable colours, lengths and earpiece colours at no extra cost. Apart from the dual driver T2, ACS also offers a custom single driver T3.
BTW, if you haven't already noticed, the T2 is a custom IEM!
General Information about the T2- Custom silicone-moulded in-ear monitors w/ colour, swirl, glitter options [no extra cost]
- Two-way, passive crossover
- Dual balanced armature transducers (Knowles ED9689, BK-1957)
- "Dual bored" sound tubes
- Frequency response of ~20Hz to 16kHz
- Impedance: 27 ohms nominal
- Sensitivity: 109dB / 1 mW
- Custom cable length and colour [no extra cost]
- 1/8" right angle plug
- Warranty period of 2 years
- Price of 499GBP inclusive of delivery and impressions if purchased from an ACS authorised outlet.
Equipment Experience
Having only been an "audiophile" for two years or so, my experience is limited. However, I have been trying to audition as much gear as possible during these past couple years. Please see my profile for more info.
Home rig: TEAC Esoteric X-03SE -> Chord CPA3200E -> Chord SPM1200E -> Focal JMLab Diva Utopia Be and unamped HD650 out of any source/receiver
University Desktop rig: Foobar/SSRC-Ultra-96kHz -> M-Audio Audiophile USB -> Stax SRM-006tMk1 -> Stax SR-404 (retired), Sennheiser HE60, Grado RS-2
Transportable rig: Foobar/SSRC-Ultra-96kHz -> Echo Indigo DJ -> ACS T2
Portable rig: 5.5G iPod Video 80GB -> ACS T2
My IEM history: ER6i -> ER4P -> ER4S -> E4c -> E500 -> T2. I have also listened to the UM2 and owned the iM616 very briefly.
Ordering and Fitting
Prior to making appointment with my audiologist at the House of Hearing, Edinburgh, I was in email contact with Andy. He was absolutely incredible and gave me a heck of a lot of help. I bombarded him with dozens of questions and he answered each of them patiently with plenty of detail. Anyone who has been in contact with Andy will know this first-hand. In general, the customer service I got was top notch. There was really very little, if anything, which I could fault.
Now I had never been to an audiologist in my life, let alone had impressions taken. It was very disconcerting at first, but the whole process only took about 10-15 minutes. First of all, my ears were checked for excessive earwax. Being Asian, I don't have wet, fluid-like earwax. Apparently, the had something to do with genetics. A black piece of cylindrical foam was pushed deep into my ears at which point I found it terribly irritating. I asked audiologist how close to my eardrums the foam was and my goodness I was freaked out when I heard him say, "A bit less than a centimetre." "Woah!" Nevertheless, what had to be done must be done so I kept my mouth shut and let the audiologist continue on. I was relieved to hear that the foam was attached to a string. Anyway, the audiologist then took two blobs of white and greenish coloured goo, mixed them together and stuck it inside a plastic syringe. What happened next was something that I had never felt before: the cold goo entered my ears like a slimy slug and for a second, I thought I had gone deaf. Both of my ears were subjected to this ruthless penetrative invasion and I sat there for 5-6 minutes waiting for the goo to cure while the audiologist strutted in and out of the consulting room like a kid with no toys to play with. Boy was I happy when he finally pulled them out.
What happened next was another unforgettable moment: handing over the cash. In my wallet were 25 20GBP bills waiting to be released. My wallet was so fat that the notes were overflowing. "Thanks you very much, Mr. Law. That will come to a grand total 499GBP" said the guy behind the cashier. *Cha-ching* Yeah, tell me about it; it certainly was a
grand total. With a wave of grief and despair, I handed over all 25 of my precious 20GBP notes. Even the Queen on the Bank of England notes looked sad
I was told to wait 28 days. As I reluctantly left the clinic with a pound coin and a flimsy receipt, I breathed a sigh of relief and made my way home. The date was 10 January 2007.
>>>Fast-forward >>>
On 12 February 2007, I received a letter in the post: "Your earmoulds are ready for collection" My eyes widened and a grin formed. I had just been to two boring lectures and this was exactly the type of stimulation I needed to wake me up. Today was
the day I had been waiting for. Needless to say, I made my way to the House of Hearing without any delay. When I got there, I was warmly greeted and the usual lame chat ensued. "How are you doing? It's a cold day isn't it. Did you get here fine?" bla bla bla "FFS, GIVE ME MY IEMs!" I thought to myself. And then they appeared. Without further ado, let's have a look at them in detail.
The Package
Inside the neat, jet-black, bomb-proof, personalised, S/N'ed Pelican case was an instruction manual, a 7ml tube of Elacin Otocreme and a black, faux leather, ACS embossed soft carrying case. Where were the IEMs?! Well they were inside the carrying case.
*sigh of relief* Also inside was an Elacin wax-loop. This should come in handy. It would be great if I could find one of the foam inserts for the Pelican case with removable foam cubes.
In the instruction manual were a bunch of boring care and maintenance notes plus some more on how to put them on. Pretty daft stuff huh? Yes and no. Actually, what is in the instruction manual is
very useful and an absolute must-read before usage. I also found out that my IEMs were made by none other than Andy himself! [EDIT: I have been informed that it was Andy the ACS lab manager who made them
]
Fit
They were more or less what I expected them to look like: cute, soft, and beautiful! I felt like an idiot not being able to put them on at first. With most things, how the item is used is more or less self explanatory. However, I actually had to look in the user manual for guidance! To my dismay, the user manual didn't really help at all so I resorted to using what was left of my grey matter, more commonly known as intelligence. For the next few frustrating minutes, I fought to put them on. It was so much hassle. Eventually, I got it. As a few days passed, putting them on was no longer a chore. It now takes me about 3-5 seconds per ear. It is also advisable to use spread a thin layer of the included Elacin Otoferm lubricant onto the the stalk and the inner surface before the first insertion so as to ease the insertion.
The fit is more or less perfect and I am very happy that it is so. I have heard enough horror stories on Head-Fi of custom IEM users having to send their poorly fitted IEMs back numerous times. I dread having to do that and I guess I was lucky. The audiologist that I 'used' was recommended by Andy and House of Hearing, Edinburgh was on ACS's list of recommended outlets so I was in good hands. I tested the integrity of the seal by using the Sensaphonics Seal Test, which can be downloaded from the Sensaphonics website. I am happy to announce that my IEMs passed with flying colours. What also surprised me was the robustness of the seal. I made closed-jaw impressions, but the seal doesn't break when I have my mouth wide open! This may be the advantage of soft silicone moulds vs UV-cured acrylic moulds that Westone and UE use.
Isolation and Comfort
There was nothing particular special about the isolation. Yes, the isolation was clear superior to that of the E500 whether I used Comply, Shure universal, tri-flange, soft-flex, etc... However, I have a feeling that the ER4P with tri-flange has about the same level of isolation. Anyway, the isolation is definitely sufficient. Comfort is also stunningly good. Even with Comply foamies, there was a limit to how long I could have universal IEMs on before my canals felt sore and irritated. With these IEMs, I could leave them on for a much longer period. The longest ever was about 8 hours at which point I had to take them off because of non-comfort-relating reasons. Solid
9.5/10 (what do you call someone who doesn't believe in perfection?)
Materials and Construction
I had mine made in the usual transparent silicone with a clear 46inch cable in the over-the-ear configuration. The cable has a very handsome silver-braided-look and is virtually non-microphonic. I would have to physically rub the cable to induce any noise. The IEMs themselves are soft and look well made. One can clearly see the two balanced armature drivers pointing into their individual sound tube. I am under the impression that dual bored IEMs have a cleaner sound than their single-bored counterparts because the two channels are not mixed until they reach the inside of the ear canal. This in itself renders custom IEMs superior to universal IEMs because the stalk of a universal IEM is simply not wide enough to accommodate two sound tubes.
The construction itself is robust and of very high quality. The soft silicone may very well have superior shock-absorbing properties compared to the UV-cured acrylic UEs and Westones. I'd never drop them anyway, but it's comforting to know that they won't ever crack open. I'm pleased with the aesthetics although I have
once been asked whether I had hearing difficulties. That was quite funny as my friend started talking to me and then I had tell him to stop while I fiddle around with my "hearing aids". I then popped them out and asked him to repeat what he had said. At which point, he asked me whether I was wearing hearing aids. LMAO. Anyway, for excellent construction and ahem, looks -
9.5/10
Music
Schumann String Quartet No.1 - Zehetmair Quartet
Beethoven Octet in E flat major - Camerata Freden
Mendelssohn Octet in E flat major - Academy Chamber Ensemble
Shostakovich String Quartet No.8 in C minor - Eder Quartet
Brahms Violin Concerto in D major - Anne-Sophie Mutter, New York Philharmonic/Kurt Masur
Tchaikovsky Piano Concerto in B flat minor - Van Cliburn, Symphony of the Air/Kirill Kondrashin
Kreisler Praeludium and Allegro - Salvatore Accardo
Beethoven Violin Sonata No.9 "Kreutzer" - Maxim Vengerov, Alexander Markovich
Brahms Symphony No.1 in C minor - Berlin Philharmonic Orchestra/Claudio Abbado
Mahler Symphony No.2 "Resurrection" - Chicago Symphony Orchestra/Sir George Solti
Liszt Hungarian Rhapsody No.2 in C-sharp minor - RCA Victor Symphony Orchestra/Leopold Stokowski
Stravinsky Firebird - London Symphony Orchestra/Antal Dorati
Dvorak Stabat Mater - Atlanta Symphony Orchestra and Chorus/Robert Shaw
Cantate Domino - Oscar's Motet Choir/Torsten Nilsoon, Alf Linder, Marianne Mellnas
Bach Passacaglia and Fugue in C minor - Peter Hurford
Haydn Missa in augustiis, Hob.XXII:11 "Nelsonmesse" - Monteverdi Choir, English Baroque Soloists/John Eliot Gardiner
Schubert Die schone Mullerinn - Fischer-Dieskau, Gerald Moore
Tchaikovsky Symphony No.4 in F minor - Budapest Festival Orchestra/Iván Fischer
Bach Toccata in D minor - Robert Noehren
Liszt Sonata in B minor - Alfred Brendel
Ysaye Sonata No.2 à Jacques Thibaud in A minor - Maxim Vengerov
MacMillan Veni, Veni Emmanuel - Colin Currie, Ulster Orchestra/Takuo Yuasa
Bantu - Los Angeles Guitar Quartet
天瀑 - 絳州鼓樂團 <- Chinese percussion
Carrickfergus - Charlotte Church
Fascinating Rhythm - Ella Fitzgerald
Honeysuckle Rose - Ella Fitzgerald & Count Basie
Don't Know Why - Norah Jones
Come Away With Me - Norah Jones
Limehouse Blues - Arne Domnérus Band
Paradise City - Guns 'n Roses
Sweet Child O' Mine - Guns 'n Roses
Walk of Life - Dire Straits
So Far Away - Dire Straits
Riding With The King -Eric Clapton, B.B. King
Snow (Hey Oh) - Red Hot Chili
Aeroplane - Red Hot Chili Peppers
Sunday Morning - Maroon 5
Harder to Breathe - Maroon 5
All Star - Smash Mouth
Black Shuck - The Darkness
Back in U.S.S.R - The Beatles
The Dark Side of the Moon - Pink Floyd
Smells Like Teen Spirit - Nirvana
Sound Quality
Bass
Coming from the E500, I was no doubt expecting a lot. Admittedly, the quantity is less, but that is where the E500's superiority ends (2 bass drivers vs 1). I am pleasantly surprised by the extension, power and detail. Whether the bass note is coming from a timpani, organ, double bass or bass drum, there is a great deal of attention to detail and the timbre is very consistent with the actual real-life sound. Percussion has never sounded better. Think ER4-type bass, but with heaps more power while retaining the same degree of control. Never do I get the feeling that the bass is lacking in power, nor do I find it overpowering. In other words, the attack and slam is very accurate. This makes for an extremely thrilling listen. It copes with fast, deep, complex rhythms with ease while conveying the right amount of weight behind each percussive beat. This is something that the SR-404 is incapable of doing. The SR-404 manages to reproduce mind-blowing complex passages and
even more detail, but ultimately lacks substance. In this particular respect, the T2 reigns superior which is a lot to say for the lil' fella.
If I were to be critical, the bass is on the warm side and I want more clarity. Detail does not equal clarity. The T2 has a tremendous amount of detail in the bass, but not enough clarity. I think that clarity may be linked in with the relatively long decay. Coming from JMLabs Diva Utopia Be speakers, I am very used to deep, transparent-sounding bass so I am very demanding indeed:evil: Compared to the HE60, the T2 has a much more punchy bass with greater bass extension. The bass reminds me of the HF-1 and to some extent the TakeT H2. All in all, I'd give the bass an
7/10 for
excellent power and detail but a general undesirable warmth which contributes to a lack of clarity.
Midrange
This constitutes the bulk of the sound we hear and hence I am particularly pedantic about getting the midrange spot on. I am pleased to say that the T2 perform spectacularly. The upper-mid thinness and colouration that plagues the SR-404 is non-existent. While it isn't as smooth as the E500's midrange, it is far more accurate and true-to-life. I listen to heaps of classical and vocals (mids-orientated music) so I am extremely irritated by headphones that fail to reproduce realistic sound. Violins have just enough woodiness and scratchiness while retaining the deep, resonant, golden tone. Woodwinds and brass have just enough warmth. Again, clarity and purity of sound is very,
very slightly lacking. Maybe I'm used to the electrostatic presentation, which has an element of purity that is simply unmatched.
Vocals, however, are more or less perfectly rendered. I don't feel the T2 really losing out to the SR-404 in terms of human voice. In fact, I enjoy listening to large vocal ensembles on the T2 more than the SR-404. The SR-404 make me analyse the different registers with a magnifying glass where as the T2 is more macro-orientated and looks at the "big picture" instead. The T2 also has a smoother sounding, richer midrange which injects more life and makes the whole listening experience more interesting. When it comes to solo vocals, the T2 are equally enjoyable. The presentation is intimate and very personal indeed. The sound is sweet and alluring. Simply fantastic. There is really very few drawbacks and the overall timbre colour is reproduced correctly. The business with the lack of clarity is so minute and trivial that it doesn't hinder my enjoyment anyway hence only deserves nothing more than a passing remark. To put my thoughts into numbers, the T2 gets
9/10.
EDIT [15 August 2007]: The midrange is certainly something that impresses me about this IEM. Very organic indeed.
Treble
This alone should convince any universal IEM user to switch to customs. The detail, precision, extension (for an IEM), transparency/clarity, smoothness,
everything is simply incredible! Think SR-404 highs, but with more smoothness and substance! No harshness, sibilance, graininess, nothing! I'd really be clutching at straws if I said there was something not right about the highs [only 16kHz extension? I can only hear up to 18kHz anyway
]. Etymotic fanboys will be pleased. 'Nuff said.
9/10
Soundstage
Well, the soundstage is mediocre at best. I am quite used to the speaker presentation so there is without a doubt that headphones are inherently incapable of reproducing a deep, three-dimensional soundstage. The T2 is no exception to this phenomenon. Yes, I can determine where the sound is coming from, but what I can't tell is how far away it is. The SR-404 is far superior in this respect. There is much more air around each note, the sound is more out-of-the-head and the concert hall feel is much better reproduced. That said, I find it acceptable, but as I always rate gear purely based on the sound, the T2 only gets
7/10.
EDIT [15 August 2007]: In retrospect, I think that 5/10 was a bit unfair. With good recordings, the imaging is pretty impressive and yes, you can sense some degree of depth.
Balance and Sound Signature
It is useless to have spectacular sounding highs, mids and bass but poor coherence and transition. The frequencies must blend into each other to form one whole sound, not three distinct chunks. With the T2, there is a potential danger that the highs become unconvincingly separated from the lower frequencies because of their two-way design. This was a problem I found with the E500: There were plenty of mids and bass, but while the highs extended well, there seemed to be a barrier somewhere in the upper-mids and the result was a rather recessed highs. Fortunately, the T2 has no such problems. Otherwise, I'd be bald pulling out my hair by now. The crossover point is well hidden although to be absolutely honest with you, I have yet to hear a piece of equipment where the cross-over point is clearly audible. In general, the T2 have more of a Shure sound signature than Etymotic. Mix E500 bass, E4c mids, Etymotics detail plus a bit of warmth and you have the T2.
As you can't rate sound signature since it is quite dependent on personal tastes, I'll only rate the balance. Slightly lower midrange orientated, but has no real impact on the overall sound quality.
EDIT [15 August 2007]: Personally speaking though, I would've preferred an even more prominent highs with slightly less lower midrange, ie a more balanced sound signature. Anyhow, this is the first IEM I've purchased where it hasn't been either thundering bass with recessed highs or great highs and anaemic bass.
8/10
Noise Sensitivity
Out of the Audiophile USB and Indigo DJ, there is no hiss. However, there is a very low level hiss coming from the headphone out of the 5.5G iPod Video 80GB. The T2 is also more prone to picking up mild background hiss from recordings.
Amplification
My brief impressions using the Supermacro-IV LE (2xAD8656) with the T2. Thanks to The-One for providing the "review specimen"
Bass
There's so much of it! The T2 verge on too bassy using the SM-LE, and that's without the bass boost on! Bass has more substance behind it and is highly beneficial for orchestral works with huge dynamic range. I feel the SM-LE does allow the T2 to have greater control over the bass and hence sound less boomy.
Midrange
I'm hearing a smoother midrange with the SM-LE. I'm also getting the slight impression that the sound is slightly veiled (warmth?) and less direct. There is
more air around the instruments and they appear to be coming from a further away point (increase in soundstage? or is this placebo?). I also get a rather noticeable loss in detail here too, and a definite decrease in transparency (again, warmth?). Not good...
Treble
Slightly better without the SM-LE. Do I hear a treble roll-off or some sort of decrease in treble with the SM-LE? It's minor, but noticeable.
With a slight muting of detail and overall transparency, the SM-LE doesn't reproduce timbre as realistically, but this doesn't really bother me because the smoothness makes the T2 much more pleasant to listen to.
Features
The crossfeed didn't really add anything to my listening experience. It was obviously there, but I didn't particularly like it. I personally prefer Jan Meier's implementation.
I always listened at low gain because the hiss was too much at high gain.
P to S impedance switch was left in the off position. The T2 quite frankly sounded pretty bad with the extra impedance.
Bass boost switch was also off most of the time, although I had great fun with it listening to Guns "N Roses. Loads of tight, powerful bass! The T2 is surprisingly bassy.
Conclusion
Overall, it's a hard decision. The sound signature changes a bit. With the SM-LE, the T2 sound warmer, smoother, have slightly rolled-off highs, more airy sound and arguably better, less boomy bass (detail, quantity)like the stock sound more than the amped sound. I love how violins sound because the extra warmth really does something special to the sound.
On the other hand, there is some loss of detail and transparency. The sound just isn't as alive as before. If I may be pedantic, the sound actually sounds a bit muted and dulled.
This really makes me feel like not getting a SM-LE. Detail and transparency is to me extremely important and must not be sacrificed for warmth, intimacy or smoothness. The best systems combine all of these factors while not compromising any of them.
After all that rambling, my verdict is a thumbs down. I prefer the T2 unamped, at least not amped by the SM-LE. Not that the SM-LE is bad or anything, it's more a case of "not my cup of tea." Transparency > intimacy.
Value for Money
Now this is a difficult one. This is obviously highly subjective but in the light of the tremendous performance that these lil' fellas are capable of, I think my money was very well spent. I honestly don't think I could've found this level of quality in a universal IEM. 499GBP translates to 973USD. Is this chump change to you? Yes? Then there is no reason why you shouldn't get these. If the answer is no, you have to get these anyway. I did despite my answer being "no"
Target Customer
To quote Andy: "We developed these monitors primarily as a hearing conservation tool for musicians ... The amazing sound quality is almost a bi-product from what we set out to achieve and because the 'secrets out' in the consumer arena with audiophiles discussing the product over the web..."
Well that sums it up really
Originally a tool for professionals, now a must-have item for audiophiles seeking the very upper echelons of portable sound reproduction!
Sound-wise, I think that the T2 is extremely versatile. Anyone looking for good sound would like it. IMO, there isn't really an aspect of the T2 which is offensive and hence would suit classical, rock, jazz and metal fans alike. In this sense, it is definitely a "one-size-fits-all"... how ironic
I certainly find the sound extremely pleasing to the ear. I'd take it over the RS-2 for rock but the HE60 would still be the classical headphone of choice.
Le petit pre-conclusion
We are seriously spoilt for choice in this small, elite world of custom IEMs. There's the UE10/7/5, the Westone ES3/2/1 and soon to join custom-"3", the Sensaphonics ProPhonic 2X-S and the ACS T2/3. How in the world do you choose? There's no definitive answer. What makes the T2 better than the 2X-S? Softer silicone? Better highs? Longer warranty period? What makes the T2 better than the UE10Pro or vice versa? Silicone vs acrylic? Triple-driver vs dual-driver? Of course I do not have the answers to
any of the questions. IMHO, there is very little risk in choosing the wrong one. They are all superb examples of IEM technology taken to the most extreme. The sound signatures might be different, but I'm pretty certain they'll all be very enjoyable to listen to.
The ACS T2 is a serious alternative and competitor to all the other custom IEMs and if you're anywhere in Europe, I urge you to give them a try. The customer service is first class and they can be easily reached via email or phone.
Le grand conclusion
Le grand conclusion is actually going to be a rather short one. I've poured my heart and soul into writing this review so I damn well hope you've enjoyed reading it
Despite this being my first proper review of
any piece of equipment in my 4k-plus-near-5k posts, this definitely won't be my last. I thank you Jude for keeping Head-Fi running and all the contributors/sponsors for their continuing support. It has been an absolutely joy, pleasure and honour to entertain such a distinguished, passionate group of enthusiasts. Sorry about your wallet!
Miscellaneous Information
My email conversation with Andy of ACS:
Q: How long will the silicone last?
A: Product life on any custom ear product is around 4 years due to changes in users anatomy and the silicones we use will easily last this long.
Q: I'm also looking a bit into the long run. Say I need to have remoulds in four year's time. How much will I have to pay?
A: We currently charge £80.00 for reshelling.
Q: How much would a typical repair due to wax clog-up cost?
A: We offer a 2 year warranty and as I said before, encourage our users to really look after their monitors, but removing debris from the monitors costs around £20.00.
Q: ...and what about a recable?
A: ...a recable is around £40.00. With careful use, neither of these should be necessary.
ACS T2: A Thorough Review
What glorious sound!