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Samadhi Magic Cube Review
Posted with permission from Positive Feedback Magazine, October 1998 issue.
Check out Positive Feedback Magazine at http://www.positive-feedback.com/.
Manoly's Mumblings: The Samadhi Acoustics Magic Cubes
Something New from Samadhi!
One of the delights of attending a CES is not only being introduced to some very magical sounding state-of-the-art gear, but also occasionally being introduced to stuff that advances the price/performance ratio. The Samadhi Magic Cubes, at only $1, 395, are the first speakers I've heard that I could happily live with for under $2,000, a pleasant breakthrough in the price/performance ratio indeed. From among the speakers that I've heard, the former champ for the least expensive, truly high end sounding speaker was the $2,000 Meadowlark Shearwater. The Magic Cubes are the least expensive speakers in the Samadhi line. Next up in the Samadhi line is the $1,990 Ichiban which is similar to the Magic cube except that it is a floor standing version with a s lightly larger bass driver. You will be able to read about the Ichiban elsewhere in this issue. The Ichiban wasn't ready for a real audition yet at CES.
The Magic Cubes are unusual in several ways. First, the parts quality is way beyond what you normally get in their price range. Second, the bass driver faces straight up.
Parts quality:
The Magic Cubes sport SEAS Excel drivers with silver plated voice coils. These drivers have a T-shaped pole piece, the top and bottom of which have a brass ring. Also, the top and bottom of the magnet and phase plug are brass. The poor magnetic field c onductivity of the brass affects the field distortion at the top and bottom of the air gap, thus reducing distortion with large voice coil excursions. Indeed, the Cubes never lost any composure on those rare occasions that I cranked up the volume. Ron Cox tells me that the parts used to build the cross overs are also of very high quality. By the way, Ron is a very knowledgeable and enjoyable person to talk to on the phone.
Raising the parts quality doesn't really affect the production cost by a humongous dollar amount. If a better driver costs, say, $50 more, you could raise the list price of the speaker by $50 or by $200 which is more typical. The $50 tactic enables Sam adhi Acoustics to deliver a better product at a lower price point, a decision that I wholeheartedly support. Most manufacturers only use this level of parts quality in substantially higher priced items because to use them in less expensive models would lo wer the percentage of profit.
What? The bass driver faces up?
Yup. The Magic Cubes have the bass driver facing up of all things. I've seen them face forward, down, left, right, backwards, and even at various angles in between, but never up. Could this be a mistake? Has Dick Olsher designed something crazy? Maybe it's just to prevent Phydeaux from piddling on the woofer.
The upward facing woofers even have a name: "Ceiling Boundary Ambience Enhancement" (CBAE). Let me briefly quote first from the CES flier and then from the owner's manual.
"The woofer is pointed toward the ceiling so that it operates at 90 degrees relative to the listening seat. Since harmonic distortion beams along the main woofer axis — much like treble harmonics — there is less distortion reaching the listener. The re sult is increased purity and smoothness"
"Sound energy is reflected off the ceiling to enhance ambience, while maintaining the music's clarity. This technology takes advantage of the fact that ceiling reflections are delayed at least 10 milliseconds relative to direct sound from the speakers. This is the critical time window within which the auditory system analyzes the sound at the eardrums for pitch and timbre. Reflections within this window color the sound, while reflections outside of this window enhance the impression of spaciousness."
"The second ingredient of CBAE technology is a critical directional response. The Magic Cube delivers sound energy into a room in a manner similar to that of a musical instrument. The speaker is omnidirectional up to a frequency of about 1 kHz. Above t hat frequency, its directional response becomes progressively more narrow. Just as a live instrument sounds real from any listening angle, the Magic Cube sounds believable from any point in the room — even from the back of the speaker!"
Okay, maybe not every point in the room sounds quite so believable. You don't want to listen standing directly above the speaker, but they do sound natural from any reasonable location. You definitely don't have to sit with your head in a vice knowing that if you move an inch this way or that the whole tonal balance and timbre of the picture will change. I'm continually amazed that some "head in the vice" speakers continue to be recommended by other popular magazines. Of the four audiophile magazines t hat I read regularly, Positive Feedback is the only one that I've never seen give a good review to a bad piece of equipment. Hmm... back to the subject at hand. The Cubes do present hall ambience very well when it is available on the recording.
Set Up:
The manual recommends stands to be 28 inches high. They loaned me a pair of stands that put the bottom of the speaker 28.5 inches up. For part of the review period, I placed a spacer between the stand and speaker as I like the tweeter to be up to my ea r level (a function of the height of the listening chair). I shall not mention the name of the manufacturer of the speaker stands (except to say that it was not Samadhi) because I did not care for the stands. Even without the spacer, these stands were top heavy and wobbly. I have encountered other taller metal speaker stands where filling them with sand was an option rather than a requirement. The cubes did sound better without the spacer under them. Superior results were obtained by just tilting the spea kers up slightly.
The Cubes were very sensitive to the degree of toe in. I obtained the best results by having them face directly at the listening position. The manual suggests that you set the toe in angle so that the tweeter axes intersect in front of the listening se at, so try a number of different toe in angles to find your preference (always a good idea).
Speaker placement dogma demands that the left and right speakers be placed an equal distance from the back wall and equal distances from the two side walls. I was unable to obtain really good image depth by following that dogma. (Curb your dogma! "That 's right, Phydeaux! Sit by the curb. Stay. Stay!!")
My listening room has different acoustics on the left side then on the right side. Against the side wall to the left of the listening seat is a large aquarium (an acoustic bummer). The front of the aquarium is six feet from the listening seat. If you a re using speakers, like the Cubes, that really want to be at least six feet out into the room, the aquarium means that there is no way to damp the primary reflection from one speaker or the secondary reflection from the other speaker. To the right of the listening seat, there is a nine foot wide opening, that opens into another room, so we are really talking about an L-shaped room. With the Cubes, the two reflection points on the right fall within the nine foot opening. There are other irregularities in t he listener's end of the room which tend to make the preferred listening position slightly off center (at least everything pushes the preferred listening seat in the same direction).
Once I curbed Phydeaux, I was able to get the image depth to open up a little. In general, it is a good idea to start by following the basic rules but then to make your final placement using your own ears. I think the dogma assumes that we all have aco ustically perfect (or at least symmetrical) listening rooms. Actually, changing the power cord on the digital front end from a cord under review back to my own Synergistic AC Master Coupler made a much greater difference in the imaging than the improvemen t brought about by the asymmetric speaker placement. Here is where the speakers ended up: the right speaker is 5 feet 9 and 1/4 inches from the back wall and 4 ft from the side wall. The left speaker is 6 feet 5 and 1/2 inches from the back wall and 5 ft from the side wall. The two speakers are 5 feet 6 inches apart, and the listener's ears are about 8.5 to 9 feet away from the tweeters. All measurements are to the outside edges of the speakers. If my listening room had been deeper, I think I could have i mproved the soundstaging further by getting the speakers farther out from the back wall. If I ever win the lottery, I'll design a room that is a more optimized listening environment (it would have NO other duties). With speakers that don't need to be so f ar out into the room, the room irregularities are less of a problem because the listening seat can move forward. With the last two pairs of speakers I used, I had no problems and kept everything symmetrical.
I suppose I should confess what I meant by "other irregularities" in my listening room. The Cubes imposed two forces that wanted to push the listening position backwards. First, the Cubes insisted on being farther out into the listening room. Second, t he upward facing woofers tended to make listening better if you were farther away from the speakers. In order to move the listening seat straight back, I would have had to either take my oversized desk out to the dumpster or find another place in the hous e to put it. I could not do either. (Besides, having the desk in the listen room means I can listen while I'm working at my desk.)
By moving the listening position two and a half feet to the side, I was able to back the listening position up by another four and a half feet. That was an improvement just by itself, despite the fact that the listening position was now two and a half feet to the side of the sweet spot. The final result of this chain reaction was a decision to try to move the sweet spot over two and a half feet to the side. Thus I arrived at the final, asymmetrical speaker placement described in the previous paragraph. Since the fish will be going to a friend's pond, I can get rid of the aquarium, and possibly move the desk to the aquarium's location. So I could (just maybe) enjoy symmetry the next time I have speakers that want to be way out into the room.
To subwoof or not to subwoof:
Phydeaux says subwoof. Actually, Phydeaux just says woof. He is, after all, only a dog. Although the Cubes are very enjoyable and satisfying without a subwoofer, I enjoyed them more with the addition of a subwoofer. Here is what I heard listening to th e 1/3 octave warble tones . . . 200 Hz, 160 Hz, 100 Hz, and 80 Hz, all played at the same level. 125 Hz and 63 Hz were both just slightly down; the 50 Hz tone was down quite a bit, and the 20 Hz tone was very faint. This jives with the specs in the owner' s manual (60 Hz - 20 kHz, +/- 3 dB). What this means is that unlike some other good sounding mini monitors, the Cubes go down far enough to mate well with my subwoofer. They also go down far enough to be quite enjoyable without a subwoofer. (If they didn' t, I wouldn't have been so impressed with them back at CES).
I have now heard four iterations of the Cube: the pair I heard at CES, the first review pair that showed up here in Kingman which was a bit brighter sounding, the second pair that came to Kingman sporting a brightness pot which necessitated changing th e base reflex port in back, and the third pair to arrive in Kingman with the much improved cross over. I mention the four versions here because we are talking about bass, and although I didn't A/B the different versions, it is my impression that when the bass reflex port changed, the Cubes lost a little bit of bass response (other improvements more than compensated though).
I have set up the bass in three configurations: first, with no subwoofer; second, with the subwoofer in between the preamp and the amp in order to cut off the low frequencies from the Cubes; and third, with the subwoofer coming out of the second pair o f preamp out jacks that I added, thus allowing the full range of signal to go to the Cubes. I achieved very good subwoofer integration both ways, and I did most of my listening with the third option (subwoofer in parallel). It would seem that passing the signal through the extra interconnects and the extra crossover caused the loss of just a bit of high frequency extension and image depth. The reason I say "it would seem" is that I changed interconnects at the same time.
Changes to the final version of the Cube:
The final version of the Cube saw a change to the crossover for the tweeter. It went from a second order to a more complex third order crossover. The improvement in sound was quite dramatic. The brightness pot also changed. It now covers a less broad r ange, and fine control is possible. I very much like this adjustability. If you change to brighter interconnects or less bright output tubes or whatever, you can fine adjust the tonal balance. The brightness control also allows for pairing the speakers wi th a wider selection of power amplifiers. However, the amount you can adjust the brightness is now less than the amount of brightness change that can be encountered by changing cables. Since most speakers I've seen aren't adjustable at all, I guess this i s a very minor complaint. Also, the brightness pot is now backwards (clockwise is less bright instead of more bright), but this is an even more trivial complaint.
A lot of air gets pushed out of the port in the back of the Cube, and you can feel it on your hand from two feet behind the Cube. This is just something I happened to notice when I was adjusting the brightness after changing interconnects (a very handy adjustment indeed).
The third and fourth versions of the Cubes were more amplifier friendly. With the second version, I had to either dial in negative feedback, or switch at least one pair of output tubes from triode to pentode to keep the Baron/Magic Cube combination fro m sucking some of the high frequencies and some of the life out of the music. With the last two versions of the Cube, the all triode mode with no negative feedback was very successful, so the version that will be hitting the stores will be easier to drive then the older versions were.
Ye old basic sonic observations:
The Cubes are very pleasant to listen to. They are quite highly detailed and yet not analytic or fatiguing. They have a superb tonal balance and a wonderful truth of timbre. Compared to my B+W 802s, the Cubes make acoustic guitars sound more natural, more like real acoustic guitars and less like hi-fi.
The Cubes also image much better. On the best recordings, the soundstage width can extend at least a foot and half to the outside of each speaker. The soundstage is about 5 feet high. This is absolutely awesome, and I've not heard better in this regard . The soundstage depth I was finally able to obtain, however, is less than the height. Positive Feedback's Stu McCreary tells me that the soundstage depth on the Ichibans is world class. I was disappointed when I failed to duplicate this with the C ubes, but that might not be due to the Cubes themselves; it could easily be somewhere else in my system, which is made up of somewhat humbler stuff than Stu has. The images within the soundstage were sometimes almost completely rock solid and sometimes no t, as I was changing and breaking in tubes, interconnects, and power cords during the review process.
On track 11 of the Analogue Productions' version of Janis Ian's Breaking Silence, the physical orientation of the piano was fairly well delineated. This is a really great two microphone track that on state-of-the-art equipment almost physically places the piano in front of you. The Cubes, in conjunction with the rest of my system, may not have nailed down the precise location of each piano string, but it came closer than many far more expensive systems.
On track 4 of Patricia Barber's Cafe Blue, the top, sides, back, neck, and strings of the acoustic guitar are all fairly nicely laid out before you in 3-space. You can very clearly hear the actions of the individual parts of the instrument, but their precise physical location could have been nailed down slightly better. The guitar was a slightly fuzzy, but still very three dimensional, shape. The soundstage depth was about 3 to 3 and a half feet on the better recordings, with the exception of th e reverberation off the recording studio walls of the snapping of fingers, which was the only time I thought I heard a depth of more than 3 and a half feet.
On track 2 of the Analogue Productions' version of Janis Ian's Breaking Silence, the brushes on the cymbals were recognizable as brushes on cymbals, but on many more expensive systems, they aren't recognizable — which tells me that we have very good detail resolution. I've only heard these brushes on cymbals rendered more clearly on a small handful of systems, and they were much more expensive. The cubes have good dynamics, and they give the impression of good bass control and authority if not g reat bass extension.
The Magic Cubes are fairly attractive and should have a high spousal approval rating (with their speaker grills on anyway). My wife didn't care for the looks with the grills off (oh, the trials and tribulations of married life!) Fortunately, the grills have only a subtle affect on the sound, and the grills are very easy to take on and off.
Conclusion:
I highly recommend the Samadhi Acoustics Magic Cubes. They are amazing in the sound quality per dollar arena, and they present a very enjoyable listening experience. There are just two caveats that the reader should take into account: first is t he sensitivity rating of only 84 dB, so listen to them with the intended amplifier, not just the amp in the store, prior to purchase. Second is the fact that the bass only goes down to 60 Hz, so if the bottom octave is highly important to you, you should consider adding a subwoofer, either initially, or later if money is a big concern. The other option for you bass lovers is to check out the Magic Cube's bigger brother, the Ichiban.
Samadhi Magic Cube, Samadhi Ichiban and Ceiling Boundary Enhancement are trademarks of Samadhi Acoustics, Ltd.
Specifications:
Frequency Response: 60 Hz - 20 kHz, +/- 3 dB
Sensitivity: 84 dB, 2.83 V/1m
Impedance: 8 Ohms Nominal, 5.8 Ohms Minimum at 300 Hz, 22 Ohms Maximum at resonance
Recommended Power Amp: 50 - 100 watts into 8 Ohms
Driver Compliment: 1 inch dome tweeter with dual magnet system and silver voice coil' 4.5 inch aluminum cone woofer
Dimensions: 7.75 by 7.75 by 7.75 inches
Weight:12 pounds
Associated equipment:
Speakers: B+W 802 series II
Subwoofer: Audio Pro B2-50 (this was hooked up most of the time)
Preamplifier: AGI 511a (heavily modified)
Amplifier: Mesa Engineering Baron
Turntable: Bang & Olufsen Beogram 1700
Cartridge: Bang & Olufsen MMC 20 EN
Interconnects: Transparent Musiclink Ultra, MIT MI 330, JPS Labs SC2
Speaker wire: Discovery 123
Power cords: Synergistic AC Master Coupler, JPS Labs "the power AC Cord"
Manufacturer:
Samadhi Acoustics, Ltd.
15975 Country Road 30
Dolores, CO 81323
(505) 672-0333
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