Tweaking and "seasoning" the sound

My colleague Dave spent a lot of time at my place while the CS3.7s were in residence, helping me dial in the best sound. One evening about midway through the evaluation period, we got serious and used a measuring tape to precisely adjust the speakers' placement so they were exactly the same distance from the back and side walls, to within a fraction of an inch. After listening a little more, we also decided that the toe-in might not be optimal, so we shifted the speakers so they fired straight ahead.

Our adjustments reduced but didn't totally eliminate the sound's sometimes edgy tendencies. At that point, we were joined by another longtime audiophile and former Crutchfielder, Mike W. Mike was quite impressed by the CS3.7s, and was shocked when he learned they are a 3-way design. He described the sound as more seamless and coherent than he'd ever heard from a 3-way speaker. Mike knows quite a lot about speaker design and even built a few many years ago.

Mike is also a big fan of tube electronics and had brought along his Scott Nixon TubeDac, a physically tiny digital-to-analog converter. The TubeDac added just the right touch of warmth to CD playback, making discs that had sounded a little steely much more listenable. The sound didn't go all soft-focus, either. We were hearing tons of detail and a large 3-dimensional soundstage — the only area lacking compared to my DAC was deep bass extension. So, when Mike offered to let me borrow the TubeDac for the review period, he didn't have to ask twice.

Glimpses of greatness

A few days later, I hosted a listening session and invited the other home audio/video writers over to check out the CS3.7s. Not surprisingly, this was one of the best-attended sessions ever. As always, everyone brought some of his/her favorite music to share.

The more experienced listeners were struck, as I was, by the THIELs' seamless top-to-bottom response. I've put a fair amount of time and effort into optimizing the transition between my Sapphires and subwoofer, but the CS3.7s showed me that I still have a ways to go.

Imaging and soundstaging were consistently excellent. Sound extended well beyond the speaker cabinets when the program material called for it. Overall image height was a bit taller than with my speakers. The compact 2-way Sapphires do a superb "disappearing act" — floating a 3-dimensional image that seems completely independent of the speakers. This is a much more difficult trick for large floorstanding speakers to pull off, but the CS3.7s succeeded admirably. Where the THIELs really shone was on classical, jazz, and other acoustic-oriented music.

The THIELs' bass was always tight and musical, never overbearing or boomy. But it didn't match the extension and impact of my powered subwoofer (few full-range speakers can keep up with a good sub). For example, on Mickey Hart's Supralingua CD there are deep bass pulses where my subwoofer launches a pressure wave you feel as well as hear. The CS3.7s stayed tight as far down as they could go, but they'd eventually fade out while the sub just kept going.

Don't get me wrong — all of the listeners thought the bass sounded great and some thought I'd left my subwoofer on. Later, when I checked the CS3.7s' bass response using a test disc, I found that in my room the THIELs' output was rock-solid down to 40 Hz. By 35 Hz, it had rolled off audibly, and below 30 Hz there was very little going on. Listeners who prefer that full-body, subterranean bass impact should consider one of THIEL's Smart Sub powered subwoofers.

My general feeling has been that if an audio component makes recordings sound more different than alike, it's probably doing something right. The CS3.7s did this to a greater extent than any speakers I've lived with. I mentioned earlier that I was frequently hearing details I'd never noticed before. A good example is the SACD version of Bela Fleck's classic, Drive. Over the CS3.7s I heard the sound of picks striking strings as these amazing players traded blistering bluegrass solos. Just as a singer's intake of breath becomes part of his/her phrasing, the sound of the picks added to the drive of the music.

This remarkable transparency cuts both ways, however. Because they're so revealing, the CS3.7s are very sensitive to equipment, room, and recordings. If you try to use these speakers with ordinary sources or amplification, you may miss much of what these thoroughbreds can do. It's similar to the way new owners of high-definition TVs are sometimes disappointed by the way standard satellite or cable TV fare looks on their big, razor-sharp screen.

Different room, different story

There were times during the evaluation period when I wondered if the CS3.7s were simply too much speaker for my room. The dimensions are 13.5 feet wide, 24 feet long, and a hair under 8 feet tall. My suspicions were confirmed upon hearing the CS3.7s in Crutchfield's large acoustically treated training room, which is quite a bit longer and wider than my listening room, with a much higher ceiling. Sound during the training sessions was much bigger and more relaxed, and bass extension was far superior.

Room issues aside, it was a pretty fair comparison because we used PS Audio electronics to drive the THIELS during the training sessions, and I use PS Audio gear at home. Several folks who attended the training said it was absolutely the best sound they'd ever heard in that room. I've attended hundreds of sessions down there and I completely agree.

What I learned

Thiel's new CS3.7s are hugely impressive speakers. Matched with high-quality source components and amplification, these speakers can deliver a deeply immersive listening experience. Their sound is unbelievably transparent and revealing; you hear deeper into the mix.

I ended up respecting the CS3.7s more than loving them, but I honestly feel it's due more to the limitations of my setup and room than to the THIELs themselves. Because the CS3.7s are several inches taller than my speakers, and were positioned firing straight ahead rather than toed in, they interacted more with the room than my Sapphires, in ways that hurt the sound.

I understand now why reviewers for high-end audio journals like Stereophile and The Absolute Sound typically keep speakers under review for several months. At this level, we've gone beyond simply doing the basic job of a loudspeaker and have moved into rarefied territory where a component performs more like a precision instrument. Which is precisely the performance many demanding audiophiles are searching for.

After spending just two weeks with CS3.7s, I'm convinced that I failed to take their full measure. The sound continued to improve right up to when I had to box 'em up and bring 'em back. I'm confident they would sound better in a month, and better still after six months. And I know I could have coaxed even better sound from them given more time to experiment with ancillary components.

Anyone shopping for speakers in this price range should make every effort to hear the THIEL CS3.7s.

Thanks to Jim and Ken and Gary at THIEL for their helpful setup suggestions. And a big thank you to fellow Crutchfield writer Dave Bar for his invaluable insights and assistance during the evaluation (not to mention helping me unpack and pack up these bad boys!)