This review began with my search for a speaker system to help turn my office into a new listening room. It gradually transformed, however, into a search for a system that was more musical or forgiving of hardness of the upper midrange in older classical CDs, and the equal hardness created by excessive close miking and efforts to emphasize “detail” in more current recordings. In short, I found myself creating a system that would be musically realistic with ordinary recordings rather than provide ultimate performance with the best recordings.
I should acknowledge the work of my colleagues Paul Seydor and Jonathan Valin. I drew on both their past reviews of Quad electrostatics, and talked to Paul at length before I bought a pair of 2905s – the act which started this review.
If you wonder why I should focus on making ordinary recordings seem more musically accurate, let me remind you that TAS was founded around the search for musical realism and not perfection in engineering – a goal that at least part of the recording industry and part of the high end seems to have forgotten. It is also a fact of life that I have well over 1,000 CDs whose problems become all too apparent on a reference system that is tuned to be as accurate and revealing as possible, and which lacks tone controls and any other way to compensate for the problems in the recording.
I spend a good part of my life traveling to areas where listening to live music is virtually the only sane way I have to relax. Even in the bright halls and in Asian countries where music often has a higher pitch, I never hear the level of upper midrange energy, the lack of lower midrange warmth, and the hardness that I hear in far too many US and European classical recordings. I’ve heard musicians play badly tuned instruments, and bad musicians become shrill through mistakes or poor judgment, but I have never heard good musicians play in ways that alter timbre and produce artificial detail at the cost of hardness to the extent that many CDs and some SACDs do.
Go to any live concert of chamber music, listen to any other music emphasizing strings and woodwinds, listen carefully to massed strings, pay close attention to soprano voice, or simply listen to someone actually play a grand piano. Compare what you hear to far too many recordings played through some of today’s best and most accurate equipment.
If you can’t hear the same types of musical detail when you stand only 10 feet away from a live musician, and if you can’t the same balance of “highs” when you listen to live music, you should not hear them on recordings. Here, I may disagree with many of my colleagues who listen primarily to popular music. With classical music, the issue is not whether you can hear something new – or more “detail” – it is whether you can hear what is musically natural and musically relevant.2
A Strad should sound exactly like a Strad.3 A Soprano’s voice should not emphasize breathing sounds and harden. A Steinway or Bosendorfer should sound like a grand piano, and never have hints of sounding like slightly off tune upright. A loud flute should be a source of pleasure, not irritation, and so the upper register of the clarinet.4
2 I suspect we all have our own examples, some glaring and some more subtle. To provide more subtle examples that seem appropriate to high-end audiophiles, let me compare two recordings. The Pierre Fournier performance of the Dvorak and Elgar cello concerti on Deutsche Grammophon is a lean and hard remastering of a very good performance in spite of the fact these are full concertos. It becomes somewhat fatiguing and unpleasant to listen to without some help from a tone control or equalizer. In contrast, the Cleveland Quartet recording of Dvorak string quartets on Telarc is much more musically natural even though unsupported strings should normally have more treble energy.
3 If you want a practical example of what I mean when I say that a Strad should sound like a Strad, compare two very good and naturally balanced recordings that both use older instruments. Take the L’Archibudelli and Smithsonian Chamber Players recording of Mendelssohn-Gade Octet for strings [Sony Vivarte]. This recording uses all Stradivarius instruments. Compare it with the Smithsonian String Quartet recording of the Beethoven: The Early String Quartets, Op. 18, [Smithsonian Collection of Recordings]. The second recording uses instruments made by a variety of makers during the mid-1600s to mid-1700s. Even a slightly lean system will blur the sonic differences between them.
4 These problems don’t just occur with older recordings. Compare the natural sound on Larry Archibald’s recording of Antony Michaelson and the Michaelangelo Chamber Orchestra performing the Mozart Clarinet Concerto (K2622) [Musical Fidelity SACD] with the somewhat brighter and harder recording of the same work by Martin Frost and the Amsterdam Sinfonietta [BIS SACD].
These problems are far less apparent in popular, jazz and rock recordings, or in classical symphonic music and large ensembles. Problems in upper midrange timbre and the natural musical sweetness in the detail of instruments with large amounts of upper midrange energy are less apparent given the mix and instrumentation involved. They are all too common; however, in older CDs of chamber music, solo instrument, and small ensembles CDs, and they are also present in about 20-25% of today’s CDs and SACDs. They also are far more striking in recordings of older chamber music – and female voice and solo instruments like the violin, piano, clarinet, flute, etc. – than with orchestral music. The problems do occur with acoustic jazz percussion, piano, and sometimes clarinet and so on, but they are considerably rarer.
At the same time, enough high-end audiophiles with very different tastes in music from mine do prefer “warm” tube equipment, and speakers with a rise in the bass and a dip in the upper midrange, to indicate that I am scarcely alone in worrying about these problems. There do seem to be a significant number of audiophiles who not only want system that are not colored but also want ones that emphasize the natural timbres and levels of detail in live music.
Quad 2905 Electrostatic Loudspeaker
So why did I think of a Quad system in a search for musical realism in reproducing older CDs and today’s close-milked and over produced recordings? To be honest, I didn’t. Jonathan Valin and Paul Seydor’s reviews of the newer Quad ESLs had captured my attention, and I was looking for a pair of ribbon or electrostatic speakers to serve as a sonic contrast to the Vandersteen 5As I use as a reference. I was also looking for speakers light enough to make moving them practical when I had to adjust a system to review new components. (A problem that made me give up on the massive—but otherwise superb—TAD-1s).
I started out by listening to ribbons and taller planers and electrostatics, but height and listening room characteristics made the room a difficult one for the Magneplanar 20.1s and other “tall” planar speakers. I’d been impressed by Jonathan and Paul’s reviews of the new electrostatics, and I’d been impressed by my own earlier listening. As a result, I moved on to the Quad 2905s.
I’m more than glad that I did. I won’t repeat all the details of Jonathan’s excellent review here (TAS, issue 186, November 2008). I would, however, like to reinforce some of his comments and add several notes about how to use the Quad 2905s.
First, let me reinforce the fact that the Quad 2905 is an extraordinarily accurate and realistic speaker with superb midrange performance, very good highs, and extremely accurate bass down to something approaching the deep bass (flat to below 45Hz with pink noise even at average levels of 90dB and useful response to around 31Hz). In fact, I was surprised to find that I could raise the volume to levels louder than I want to hear with the strongest and deepest organ passages on a truly demanding recording like the Jean Guillou performance of Mussorgsky’s Pictures at an Exhibition [Dorian Dor-90117]. A lot of large cone woofers give out or distort sharply on this recording long before the Quad 2905s do.
But, the 2905 is not a “rock speaker,” if rock means super-loud. I don’t want to call it an “acoustic” speaker because it does just fine with reasonable electronic recordings, but ultra-loud is not its natural forte. I also did encounter times when the protection circuits kicked for reasons I could not initially understand, although it turned out that the speakers were actually functioning perfectly. The 2905s sometimes shut down in passages with average listening levels be well below their design limits, which equates to around 103dB in my listening room.
The problem turned out to be that if a recording has massive amounts of deep electronic bass at frequencies you can’t hear, or other really quick peaks that go well above 103dB, the protection circuits will kick in. Be aware that a standard analog Radio Shack SPL meter does not show this. It takes much more professional piece of equipment like the Phonic PM2 to show the real SPL level.
I would note, however, that the Quad 2905 is so clean a speaker that like its very best competition, you can find yourself underestimating the average SPL level. This works well with some music, but not with most acoustic music with significant highs and upper midrange energy. Be careful to keep the music at natural listening levels if you want the most realistic experience. Too little volume and the bass and upper octaves get lost. Too much, and the whole character of brass, woodwinds, and strings tends to brighten in the upper midrange.
Second, dipoles are no harder to place than other speakers. As Roy Allison pointed out in some pioneering room measurements back in the 1960s, all reasonable listening rooms present serious speaker placement problems for all types of truly full-range speakers. In fact, I found the Quad 2905s surprisingly easy to place, and two to three feet of distance from the rear and sidewalls worked out quite well. I would, however, strongly suggest that you use at least a quarter-octave spectrum analyzer, pink noise, and bass warble tones to place them where they measure well, and then tweak by ear.
No one can hear the size and frequency of the peaks and valleys in the lowest octaves. You have to measure them to know what is happening, and inches can matter in getting rid of the worst of them in the range of positions where you listen. This is a concern with all speakers, but your experience with “boxes” may well be misleading with dipoles. You should start with some level of measurement. I use a combination of the Tact 2.2x and the Phonic PM2, but there are many programs that will work on a laptop.
I also would recommend that you try wider spacing and much sharper degrees of toe-in with the 2905s than you would with box speakers, even to the point of aiming the 2905s so each main axis crosses in front of the listening position. These are not yesterday’s Quads. Unlike the Quad 57s that I used in my first real high-end system, the 2905s do a good job of dispersing even the highest frequencies in the real world musical spectrum. Unlike both the Quad 57s and Quad 63s, they don’t need to be raised or stacked to get good vertical dispersion or limit floor and rug effects.
As is the case with most modern and flat speakers, however, their on-axis response can produce too much upper-octave energy if the speaker is aimed directly at the listening position (measures better, sounds worse). Moreover, diploes generally sound better if they are at an angle to the corners, rather than parallel to them, or have some damping to reduce back and side reflections. (This may explain Jonathan’s comments about the occasional spotlighting of female voice. I certainly found it eliminated some emphasis on the upper voice, flute, clarinet, strings, etc.)
The 2905s also proved to be capable of a remarkably realistic three-dimensional sound stage without forcing the listener into a single spot with an unmoving head if they are toed in enough. The realism on a wide range of naturally miked, naturally positioned jazz and chamber music recordings was both extraordinary and stable. Finding the best room location is always is going to be room-specific, but do keep experimenting until you get at least very good results. The 2905s are good with all forms of music, including the most overblown and overproduced opera staging of Wagner, but they can be truly extraordinary in reproducing the soundstage you expect from the kind of solo instrument and small musical ensemble that could actually perform in your home. Don’t waste their capabilities.
Third, the 2905s don’t really need a subwoofer, but don’t be afraid of adding one if you really need the deepest bass or want to push the envelope in terms of listening levels. Using a subwoofer will have costs as well as advantages. Adding cables, using crossover components, and introducing different (i.e., non-electrostatic) drivers does have a slight sonic impact. Ideally, use a preamp with a processor loop. But, be aware that these sonic costs will only have a limited impact on the apparent realism of even the most demanding recordings if you use good subwoofers and associated equipment.
Experimenting with an advanced electronic crossover like the Tact 2.2X is probably the best way to go. However, a REL subwoofer used as a supplement to the 2905s worked fine. So did using the built-in crossovers in Velodyne DD-18, an Outlaw LFM-1, and Definitive Technology Supercube 1 subwoofer.
I got very good results in extending the bass and slightly increasing power handling using such subwoofers. I could push the deepest organ passages to their limits with both, as well as increased realism with deep electronic bass and Kodo drum recordings. I still preferred the Quad 2905s without a subwoofer for music without very deep, high-energy bass content—but not by much. Today’s subwoofers are one hell of a lot better than they have been in the past.
I also found that I could get relatively seamless and nearly flat bass down to around 28Hz using a combination of the 2905s, a Definitive Technology Supercube 1 and the manual adjustments and measurement capabilities of the Velodyne SMS-1 electronic bass unit.5 The SMS-1 is a badly neglected unit in my opinion, and if you have a serious room problem or want flatter bass with minimum grief, it really merits your attention.
5 Do read the Velodyne and Outlaw manuals if you try using the SMS-1 – both are available here. Adjust manually to moderate the peaks and valleys in the bass; the automatic set up feature on the SMS-1 did not work well at all. Do not seek impossibly flat response. Do experiment with different crossover frequencies and slopes. Manually adjust for both Q and each frequency setting for the best results in the range of your listening positions. Do confirm your setting with pink noise and separate warble tones, and by listening to music. No one set of bass test tones or measurements can be relied upon. Also consider the Audyssey Sub equalizer. It does not provide the on screen display and adjustment features of the Velodyne, but seems to have a more sophisticated program for automatic set up.
In short, the 2905 is a great speaker that is reliable, easy to set up, and one you can upgrade to add even the deepest bass.6
6 A minor caution about ergonomics: the 2905’s speaker terminals suck. They are almost impossible to tighten properly, and are a disgrace to a speaker this good. You should either remove the plastic inserts inside them, and use truly high quality banana plugs like the Wets, or get your dealer to put in decent speaker terminals.
Quad 909 Power Amplifier
I might well have stopped at buying the 2905s if I had not previously been the owner of Quad electronics, and worked my way from Quad’s tube designs through two earlier generations of Quad solid-state electronics. I got excellent results with top quality recordings using the 2905s and my normal reference front ends, preamps, and amplifiers. The same was true of a great deal of other electronics – although the 2905s are a demanding load and amplifier compatibility is not always predictable.
For example, I got far better results with a pair of VAS Citation Two tube power amps than with the Prima Luna ProLogue Sevens, although both normally offer outstanding performance at relatively moderate cost. I could not help wondering, however, just how much Quad electronics had changed over the years – particularly now that Quad was owned by a Chinese company. Moreover, when I talked to Jeff Sigmund, at Quad USA, he casually mentioned that I should hear the Quad 909 amp, although some audiophiles felt it sounded somewhat “soft.”
And here I come back to the issue of musical realism versus high-end accuracy that I mentioned at the same of this review. Jeff’s comments struck an immediate chord with me because I remembered the Quad 303 and 405, and their accompanying preamps with considerable affection. I remembered them as being some of the most musically natural electronics around for their day. More than that, I remembered the matching Quad preamps as having a unique set of tone controls and filters that did an outstanding job of correcting for the problems in noisy LPs and analog tapes, and for the problems in all kinds of recording ranging from warm to bright.
Well, to make the story short, the Quad 909 does sound slightly “soft” compared to my reference electronics and most top high-end solid-state electronics. It comes close to the sound usually associated with a slightly warm tube amplifier. If you want to hear every transient edge, and every last possible bit of detail, this is not the amp for you. But, if you have a large to massive collection of classic and/or acoustic jazz on CD, LP, and tape, the Quad 909 power amp will provide a more musically natural sound with average recordings and does work synergistically with the 2905.
To go back to using live music as a listening standard, I don’t want to hear new levels of detail on my recordings at the cost of exaggerated upper midrange energy and an edge to acoustic instruments I don’t hear live. I also do not want to spend my life with music trapped into listening to the best recordings. I want to listen to the full range of my collection, and take advantage of today’s music servers to compare musical performances and nuances in ways that have never been practical before. I can’t do this with a purist reference system. I need enough “forgiveness” or “musical realism” – take your pick – to go from the peak performance level of listening to being able to enjoy my entire collection.
The Quad 909 is “voiced” in ways that provide this kind of listening experience. It does means sacrificing the finest level of detail on the 10-15% of my collection that is superbly naturally recorded. I’m not giving up my Pass electronics or the pleasure and excitement I get from pursuing the purist side of the absolute sound.
But, the Quad is musically realistic with ordinary recording in ways that other amps are not, and it is still very accurate. The 909 and 2905 make an excellent combination -- particularly in getting low to lower mid level detail and life out of the 2905s. A number of amps make the Quads seem most natural only at mid-level volumes.
Moreover, good as the right tube amplifier can be with the 2905s, the Quad 909 offers more bass extension and control. Like other really good solid-state amps, it makes the Quad 2905 sound more natural in the bass.7
7 Again, however, let me offer a word of caution about Quad ergonomics. The Quad 909 is a very small amplifier by today’s more extreme high-end standards. The case overhangs the rear connections, and access space for the analog inputs and speaker wiring is a bit tight. The speaker terminals also are standard twin post connectors with plastic plugs where banana jacks could fit. If you do not use the Quadlink or DB-15 connector between the Quad 99 preamp and Quad 909, you will be better off using flexible RCA cables with tight or locking RCA plugs.
SPECS & PRICING
Format: Floor-Standing Dipole with 3? Tilt Back
Type: Full-range Electrostatic
Membrane: Ultra Low Mass (0.5g/m2) Tensioned Film
Panel Elements: 6
Time Delay: Progressive Concentric Rings
Chassis Structure: Heavy Duty Composite Aluminium / Steel
Maximum Output: 2N/m2 at 2m on axis
Sensitivity: 1.5 mbar per volt referred to 1m. (86 dB/2.83V rms equivalent)
Impedance: 8 Ohms nominal
Impedance Variation: 4 - 20 Ohms
Maximum Input: Continuous input voltage (rms): 10VProgramme peak for undistorted output: 40V Permitted peak input: 55V
Frequency Response: 32Hz - 21kHz (-6dB)
Distortion (100dB at 1m)
32Hz - 21kHz (-6dB)
28Hz - 23kHz (useable)
Above 1000Hz 0.15%
Above 100Hz 0.5%
Above 50Hz. 1.0%
AC Input: 220-240V or 110-120V
63mA anti-surge, 200-240V
100mA anti-surge, 100-120V
Power Consumption: 6 Watts
1430mm x 695mm x 385mm
(add 25 - 55mm for feet)
Weight: Net 41.6kg
Maximum Power Output: 140 WRMS -8 ohms (0.5% THD), 250 WRMS -4 ohms (0.5% THD)
Maximum Output Current: 11 Amps peak each channel
Total Harmonic Distortion: ‹0.02% (140 watts, 8 ohms; 20 Hz to 20 kHz)
Input Sensitivity (RCA input): 775 mV
Output Impedence: 1.5uH parallel with 0.05 ohms
DC offset voltage: less than 10 mV
Frequency Response: 13 Hz to 40 kHz (+0dB/-1dB)
Signal-to-noise ratio: (70W): 108dB (20 Hz to 20 kHz)
Dimensions (H x W x D): (140mm x 321mm x 240mm)
Quad Electroacoustics Ltd,
IAG House, Sovereign Court, Ermine Business Park,
Huntingdon, Cambs, PE29 6XU
Tel :- 01480 447700, Fax :- 01480 431767
310 Tosca Drive
Stoughton, MA 02072
Phone: 781 341 1234
Fax: 781 341 1228