I totally agree with this review. I tried a pair out which was not custom made for my ears so I had to push these soft earphones in a bit and they were very warm, very clear and had a nice bass punch.
http://www.touchmyapps.com/2010/04/18/acs-t1-custom-fit-iem-in-review/
Conclusion
There’s no escaping the warmth of the ACS T1. But where most warm earphones lose details and tend to boom, the T1 maturely casts everything back to the listener. Sure, there is a bit of mid-bass boom, but for most genres, it fits in perfectly. Otherwise, voicing is great and mid/high voiced instruments are phenomenal. That isn’t to say that bass isn’t as amazing. It is, but there, in the depths, is a warm, free-spirit lurking. It is warm, deep, big, and at times, accompanied by a faint second voice. If you are a fan of valve amplifiers, of LP records, and soft ice cream, you will probably enjoy the T1 a lot more than you will its competitors. Still, it stands toe to toe with them in majority detail retrieval.
Finally, It is strong, looks and feels great, and is nearly flawless for out and about. The only thing ACS could improve on is the cable’s attachment to the earphone; removable cabling would be perfect for both the experimental audiophile and the violent professional musician alike! If you are a performer, the soft silicon, which flexes and re-moulds itself to the inner ear, is a perfect choice for the stage. For the lecherous techies and audiophiles, I simply recommend the T1 as an integral part of a hi-end portable system, but comes with a hi-end price
