- Published on 19 January 2009
I played the CS3.7s for about a week before doing any critical listening to break them in. Amplifier duties were handled initially by the 200 WPC Emotiva RPA-1 dual mono amplifier and later by the 500 WPC Emotiva XPA-1 monoblocks (review to come soon). With 90 dB sensitivity, you may think these speakers would be happy with a low power amplifier, maybe even a low powered tube amp. Don't. With an impedance of 3 ohms or less throughout most of the audio band, a serious amplifier is required. To really make them sing, a REALLY serious amplifier is best.
Some audio components jump out and smack you at you when you first listen to them. Others are like settling into a well-broken in easy chair. The CS3.7s were in the latter camp. One of the characteristics of a truly great piece of audio gear is the ability to get out of the way of the music, and the CS3.7s are currently the champ in this regard compared to every other piece of audio gear I've reviewed at Secrets. This is not to say that the CS3.7 does not excel any area of performance, but they are likely not going to jump out at you at first listen.
I was surprised by one area of the performance of the CS3.7s, and that was the bass. I did not expect what I heard, given the CS3.7s are rated to play down to only 32 Hz. The bass was the most tonally accurate and well integrated I have ever heard in my room. As I've said before in several reviews, my room is terrible below about 200 Hz. There are plenty of resonant modes, and a big suckout at 30 Hz. Since the CS3.7s didn't go all the way down to 30 Hz, the suckout was irrelevant.
For some reason (maybe the forward firing woofers as opposed to the side firing woofers of my normal Gallo Reference 3.1s) the bass was very well integrated, smooth and relatively free of response peaks and valleys. In addition the impact and tightness of the bass was exceptional, even with electronic music with lots of low frequency energy. While Crystal Method's "Vegas" did not cause windows to buzz in their frames, the power and heft of the bass left little to be desired. Some other reviews have presented the CS3.7 as a bit bass-shy, but in my opinion you'd have to be a serious bass freak to want more. Even then, you would want to add only low frequency extension. The bass that is there is just about perfect.
While I was most surprised by the bass, that was not the best feature of the CS3.7s sound. That midrange and tweeter are nothing short of magic. The performance of the CS3.7 in the midrange and treble are world-class. The smoothness, articulation, detail retrieval and extension of the THIELs are the best I've heard in my room. That said, they are also revealing. I could easily hear the flaws in recordings and the limitations of all upstream electronics. The CS3.7s insatiable demand for current left them a bit dynamically flat when powered by the Emotiva RPA-1.
With the big XPA-1 monoblocks, they came dynamically alive, and were able to unearth far more detail in recordings. The XPA-1s are brighter than the sweet and smooth RPA-1, which could make poor quality recordings a bit grating. This was not the fault of the THIELs, though. They reproduced exactly what was there as well as anything I've heard. They also revealed changes in upstream components very clearly. The treble presentation of my Oppo DV-983H versus my Bel Canto DAC-1.1 were as clear as day. The Oppo offered much greater perceived high frequency extension and sparkle, while the Bel Canto offered superior dynamics. The extension of the Oppo, combined with the XPA-1s and the CS3.7s could be a bit unpleasant with poorly recorded material, but this was easily remedied by using the Bel Canto for those recordings. I have yet to hear a speaker with this level of transparency that so clearly reveals both the recording and the associated electronics.
This transparency carried on with the extremely natural and lifelike presentation of timbre, again never calling attention to the speaker. Assisting this natural sound was the ability, particularly in the midrange and treble, to extract every last ounce of detail without sounding analytical or etched. A great test for this is any well-recorded use of brushes on a snare drum. Its best if the recording is not close-miked since that will pull out too much detail and make the job for the speaker too easy.
I dug out several recordings made in the 50s and 60s with non-close-miked brushes. The CS3.7s were able to make these sound realistic, capturing the sound and texture of the brushes on the head. This subtle trick is not an easy one; typically, the sound blends into white noise. Both the midrange and the tweeter were able to wring every last detail out of every recording I listened to, throughout their range. The tweeter's extension (to 26 kHz +/- 2dB, 35 kHz -3 dB) was really fantastic on well recorded material. On poorly recorded rock, with loads of digital hardness, the THIELs let you know it. Transparency has its downside. These speakers will not make bad recordings or bad upstream electronics sound good.
Another pleasant surprise was the THIEL's imaging performance. My Gallo Reference 3.1s are known as some of the best imaging speakers there are. The THIEL's gave up little or nothing to them. The soundstage was quite high, due to the high mounting location of the midrange/tweeter, but not so high as to feel unnatural. This gave the soundstage a larger feel than with the Gallos. Soundstage width might have been a touch narrower, but I can't be absolutely sure on that, as I couldn't have the two speakers set up at the same time. Soundstage depth, due to the spectacular ability to retrieve detail, was much better with the THIELs. Several recordings I thought were relatively flat, like Gomez's How We Operate gained significant soundstage depth with the CS3.7s that were gone when I reinstalled my Gallos.
Overall, I can't give more praise to the sound of the CS3.7s. They do absolutely everything well, and have zero detectable flaws. The only possible complaint I could imagine anyone having is that they lack the bottom 12 Hz of bass. Know this. If you want to maintain the sound quality of the CS3.7s AND get that last 12 Hz of bass in a full-range speaker, you're going to have to pay WAY more than $13,000. And have a forklift handy to move those gigantic speakers into position.