ACS Custom T2 Classic Custom-Fit In-Ear Monitor (Playback 61)

Superior Fit for Superior Sound

The name ACS Custom might not be the most well-known in today’s custom-fit in-ear monitor marketplace (that title probably belongs to Ultimate Ears), but the firm is certainly known by the company it keeps, with a client list that includes the BBC (BBC Orchestra, BBC Radio, and BBC Singers), Pink Floyd, Radiohead, U2, and many more. What’s significant, I think, is that many of these famous ACS Custom endorsers are known for creating music that is not only popular, but that places a premium on sound quality. To better serve its worldwide customers, ACS Custom maintains offices and in-ear monitor manufacturing facilities in multiple locations throughout Europe, the US, South Africa, Australia and New Zealand.

I had the opportunity to catch up with one of ACS’ principals, Dr. Craig Kasper, at the 2012 CES Show, where I learned about ACS. Much like the Chicago-based firm Sensaphonics, ACS believes strongly in building its in-ear monitors with earpieces made of soft-gel silicone materials, rather than the more commonly seen solid acrylic materials. As you’ll learn in this review, this particular design touch influences the performance capabilities of ACS monitors in several important ways, especially in terms of allowing an extremely comfortable fit with very high levels of noise isolation. I asked Dr. Kasper if he would recommend any particular ACS model for audiophile applications where a key objective would be to obtain the most neutral, accurate sound possible. Dr. Kasper recommended ACS’s T2 Classic Dual Driver model ($799), indicating that it was, at the time, the ACS model with the most accurate overall tonal balance.

The T2 Classic is, at least in terms of price, the middle model in the ACS lineup, positioned above the T3 Classic Single-Driver monitor ($479) and below the T1 Classic Triple-Driver monitor ($999). At first blush it might seem odd that the middle model in the range would be more accurate-sounding than the “flagship” model (at least in strict audiophile terms), but in fact this arrangement is pretty common in the world of custom-fit IEMs. What goes on is that top-tier IEMs are often designed more with the needs of performing musicians in mind, rather than targeted for customers who will use their IEMs primarily for listening to recorded music. Indeed IEMs designed for use as stage monitors often feature frequency response curves that deliberately incorporate certain strategically placed “colorations” with an eye toward helping musicians hear clearly even in the presence of extremely loud stage environments.

We reasoned, however, that most Playback readers would purchase in-ear monitors for purposes of listening to recorded music—sometimes in quiet environments, but occasionally in more noisy settings (e.g., flying on planes or riding on trains). With this thought in mind, we requested a set of T2 Classic monitors, which ACS Custom graciously provided for us to review.

OVERVIEW

Consider this product if:

• You prize IEMs that offer a remarkably well sealed, comfortable, and ultra-secure fit with excellent noise isolation. The soft gel silicone earpieces really do make a big difference.
• You want an in-ear monitor with a delicate, warm, vibrant, and highly engaging sound. But note: The same upper midrange/lower treble emphasis that makes the T2 Classic sound “vibrant” can sometimes—on certain high-energy transients—make this IEM sound slightly “spitty.”

Look further if:

• You expect your in-ear monitors to come with user replaceable signal cables (by tradition, ACS’ Classic-series monitors come with non-detachable, “embedded” cables). Note, though, that ACS’ new Live-series models, which are slightly more expensive than the Classic models, do have detachable cables plus other features. Further, ACS may soon offer standard T2 models with detachable cables.
• You’re after maximum sonic neutrality. If studio monitoring-grade accuracy is what you seek, Ultimate Ears’ In Ear Reference Monitor remains our go-to choice.

Ratings (relative to comparably-priced custom-fit in-ear monitors)

• Tonal Balance: 8.5
• Clarity: 8.5
• Dynamics: 9
• Comfort/Fit: 10
• Sensitivity: 9.5
• Value: 9.5