Sound Labs 645-8, A Review


I finally got the Sound Labs dialed in and have been listening for over a month. They are 8 foot 645's, the first pair ever made. Standard 845's were to wide for my situation. 645's are 4 inches narrower at 36 inches. I called Roger West, CEO of Sound Labs and asked if he could make me a set of 8 foot tall 645s in Majestic trim to which he immediately replied, "no problem." Two months later I had my speakers. He did not charge me a cent extra for the custom work.

The speakers arrived in two serious wooden crates with the interface/bases in two separate boxes. In spite of serious packing one speaker had a small area of the finish rubbed down to primer on the side trim, fortunately an easy fix. 
The speakers were a breeze to assemble and set up but it does take two people. You have to be careful with the grill cloth. It is as light as shear stockings. On the interface panel there are four controls. The bass and midrange controls are heavy duty rotary switches. The brilliance control is a Zero to 8 ohm 100 watt potentiometer and the bias level control is a smaller potentiometer. All of this is sealed from the environment. The build quality of the interfaces is first class, neatly wired point to point, circuit boards need not apply. The transformers are massive. After several hours of listening I had room control calibrated and the speakers adjusted to suit my room. Bass down 3 dB, Midrange 0 dB and brilliance set at 2 ohms (measured).,

At the end of a particularly loud listening session playing Mellon Coli and the Infinite Sadness, I smelt insulation burning.
After 10 minutes of sniffing around I got the the left channel speaker which was where the smell was coming from. The interface was very hot. I could keep my hand on it but barely. The speaker sounded fine. I called Roger and he informed me it was probably the brilliance control. Which it was. It left this world the next day. Roger got a new one to me the very next day. In the mean while I installed 150 Watt 2 ohm resistors bypassing the brilliance control. After an hour of loud playback the interfaces were even hotter! Something was wrong. It was my room control unit. It had inadvertently boosted 20 kHz 12 dB which the JC 1's handily plastered the Sound Labs with. ESL impedance drops with frequency. Up at 20 kHz the impedance is less than 1 ohm. The amount of current at +12 dB 20 kHz was ridiculous and I fried the brilliance control. It was not in any way the speakers fault. Modern room control units place a limit on the amount of boost that can be applied. TacT was the very first to do room control and there were no limits placed on the DSPs. 
It did not bother the transformers at all. I replaced the brilliance control in case I wanted to return the units to stock and permanently mounted the 2 ohm resistors with thermal grease. I also bypassed all the switches leaving the bias control alone. I have to reiterate that this was my fault and regular systems and modern room control would never do this. Bypassing the controls probably does nothing to improve the sound but, it makes me feel better. Now with the system blasting for hours the interfaces just get a little warm. Roger was ready to send me new transformers! Could not ask for better communication and treatment.

Now for the serious part. Some things are hard to qualify. Such is the sound of these speakers. There are significant differences between these and the 8 foot Acoustats I use to have. The physical differences are; the Sound Labs have almost twice the surface area of the Acoustats but in reality, because the individual panels are much narrower and form a 45 degree arc you are listening to a much narrower speaker from 500 Hz up. Because ESLs beam you are really only listening to the membrane tangent to the axis of your ears, the resonance frequencies of the individual panels are much different than the Acoustats because the panels are smaller and of varying size. There is no one dominant resonance frequency, the Sound Labs disperse sound evenly over a 45 degree arc relative to the Acoustats 10 degree arc. They are much less selfish, you can plainly hear the speaker right up against the opposite wall at the distance of the listening position. Everyone must remember that I cross over to four subwoofers now at 110 Hz 8th order. 
I hesitate to call these speakers neutral, maybe balanced is a better term or seamless even better. There is a uniformity across the frequency spectrum. Nothing calls attention to itself. The overall presentation is an effortless neutrality that initially sounds dull but, it is most definitely not. The high frequencies are there in spades they are just not sprayed all over the place. When you sit down and close your eyes the speakers disappear. The Instruments and voices float individually in space. Small details that were previously overlooked become evident. Distortion is vanishingly low. 
The Allman Brothers Live at The Fillmore, a recording I previously thought was sort of muddled blossomed into the first band I ever heard live at the Boston Tea Party. Butch Tucks and Jaimoe the two drummers were always difficult to distinguish. Not any more. Each one occupies his own space left and right. You know who each cymbal belongs too.
Dicky Betts and Duane occupy their own space and the interaction between the two becomes obvious. Everything is as big as life. 
Many people think ESLs lack dynamics and power. Return to Forever Returns is a fabulous reunion live recording in modern terms. At 95 dB average volume when Lenny White slams his snare drum you can feel your hair move and his bass drum slams you in the gut. You can here every note of Stanley Clark's bass even when he runs 16th notes. The special character of his bass comes through loud and clear. Close your eyes and you are there at that concert. I was there in 1975, Burlington, VT. Given the right power these speakers are as realistically dynamic as any I have ever heard and no speaker I have ever heard matches the ability of the Sound Labs to cast an image. They will also unmercifully disclose errors in engineering like putting cymbals at opposite ends of the stage giving the drummer 9 foot arms. Another favorite is putting the low registers of a piano way on the left and the treble keys way on the right with nothing in the middle. Very realistic. 
I do not know of a speaker better at uncovering subtle details. You would think Haley William's Petals for Armor was just another pop record. The synthesizer ditties winding through the background are brilliant. This record is a pop synthesizer symphony. It has to make Trent Reznor jealous. Herbie Hancock's Sextant is mesmerizing. Details I have never heard clearly before became obvious. If I get into classical music I will be here for hours tongue twisted. I am a string quartet fanatic. Cherubini brings me almost to tears. With these speakers I could go through an entire box of tissue. Each instrument occupies it's own space and the interplay between them becomes more obvious, more amazing.
Another wonderful characteristic is that I have yet to hear these speakers get sibilant. Not even a hint of it. Not on female voices, saxes or violins. They remain effortlessly smooth regardless of the recording. How do they do that? I am not even using a BBC curve. I now have no need for one. 

So, you might think I am very happy with these speakers and you would be right. The Sound Labs are the last stop for me. Not only are they the best speaker I have ever heard but they are an outstanding value easily outperforming speakers costing 6 times as much. I have never heard a speaker image like this. 

Thanx to Roger West for putting up with me. It was a pleasure torture testing his loudspeakers. A gentleman and a scholar.  

   




128x128mijostyn
TacT had the very first room correction system.
Accuphase made one too that we used at the 1998 Stereophile show. That was when I realized that if you had a standing wave, room correction wasn't going to fix it if the manifestation of the standing wave was a null rather than superposition.
mijostyn  

You need moabs, what’s wrong with you ?

Seriously, as a poor man ESL afficiando, I praise your well thought out review.

Enjoy!
@atmasphere , I don't recall that unit but you are right. There are room issues that digital EQ can not do much about without wasting a lot of power. Smart acoustic management remains crucial for the best performance. Because of my room design I have very minor nodes so there is nothing major that has to be done in the bass. It was entertaining that my problem occurred at the highest frequencies. But room control which is really speaker control serves to flatten the frequency response of the speaker in the room and more importantly allows you to match the frequency response between the speakers and give the speakers the sound you like.  After years of this I have learned exactly what to do with certain problem and I know exactly the frequency response curve I like to hear. But the physical characteristics of the speaker also remain very important. Some speakers you are never going to get a good image out of even with careful matching.
@mijostyn,
Congrats! In my biased opinion as a Soundlab owner, you've made a great choice ;-) 
I've had my A3s for about 5 years and consider myself lucky to have them every time I listen. Having heard many systems at luxury price points, very few bring me as close to the music as mine and those of others using Soundlabs. Regardless of musical genre, loud or quiet, they pull in you in ways that most speakers don't. 
FWIW, I have learned that the live end / dead end room treatment theory explained by Dr. West on soundlab.com is an important consideration. The widely quoted recommendations on room treatment are based on probably 95% of users working with dynamic cone drivers. You're off to a great start treating the wall behind the speakers first. This is by far the most critical, with some diffusion behind the seating being #2. I would suggest playing around with additional absorption and some diffusion behind the speakers if you get the chance to squeeze out that "last 1%". I found a nice enhancement with some DIY wood Skyline-style diffusors that were a fun and easy project that gets me many compliments from non-audio geeks, as "nice modern art', lol. 
FWIW, I agree that Soundlabs are not harder to work into a room if you've got a decent sized space. Side wall, ceiling and floor interactions are less than you'll find with most speakers. You will definitely get benefit from pulling them off the back wall like most speakers, but I find this to be true with most dynamic speakers too. Cheers,
Spencer