Siefert Maxim III loudspeaker Thomas J. Norton Maxim IID in June 1987
Preface: We originally weren't going to publish this review, as we were led to believe that the IIID would be obsolete by the time this issue of Stereophile appeared. However, as we were going to press, we were informed that this would not be the case. In addition, contrary to what we reported in the most recent "Recommended Components" (Vol.10 No.3), the original III will also remain in production. The fact that the IIID was modified to correct its flawed high-frequency balance, however, will be of interest: Siefert state that units manufactured after December 1, 1986, have the most recent tweeter/crossover changes.Ed.
All but the newest readers will recall JGH's highly favorable review of the original Maxim III in Vol.8 No.3. The III remains in the Siefert line, but is now joined by the new IIID, which is practically identical except for the incorporation of a 21mm open-dome tweeter manufactured by the Danish firm Dynaudio. Dynaudio drivers are notable for their exceptional power-handling capacity, but they are expensive and, largely for that reason, not widely used by system designers (footnote 1). The high power-handling facilitates the use of slow-slope crossover networks, and the Maxim takes advantage of this capability (footnote 2). In the IIID, the system crossover has been set at 2.5kHz, 800Hz lower than the crossover in the original III and actually far lower than Dynaudio recommends for this driver (they intend it to be used as a supertweeter).
My original pair of IIIDs came close to receiving a mediocre review. Ironically, the culprit was that new tweeter: the overall frequency balance was clearly skewed in favor of the high frequencies. While the treble was admirably clean and open (I noted no coloration or strain that could be attributed to the low crossover frequency), over time the excessively sibilant, over-etched sound became irritating. Just as I was about to put poison pen to paper, I received a call from Ed Miller of Siefert Research. It seemed that others had noticed the same thingreviews that appeared in print before March '87 have been of samples with this original design balance. Ed stated that Siefert had discovered a small but audible peak at 11kHz. Not to worry, said Ed, return the offending units posthaste and a new crossover change will scotch the problem.
Did it ever! The new IIID (which I have dubbed "Improved" but will hereafter refer to only as the IIID to keep this offering manageable) had a dramatically improved balance. Overall, the new tweeter was now clearly the greatest strength of the system. High-frequency response was outstanding in all respects: smoothness, extension, delicacy, detail, and consistency from soft to loud levels. While I hesitate to call anything state-of-the-art (footnote 3), since no one is really qualified to make that judgment unless he or she has evaluated absolutely everything (a clear impossibility), I will say that I have heard no other loudspeaker that is obviously superior above 5kHz.
When a designer improves a loudspeaker system in one area, he risks "unbalancing" the system, exposing weaknesses that were not obvious before. The new tweeter is clearly "faster," and more detailed and neutral than the woofer. Some may find this discontinuity mildly distracting; I found it easy to adjust to, and consider the superb new high end a more than even tradeoff.
I was not at all surprised to find that the small Maxim IIID produced an excellent soundstage. With careful setup (good stands are highly recommended; Siefert shows 20" stands in their literature but I preferred 24"), you will be rewarded with a soundstage that most larger systems cannot equal. Small speakers have a built-in advantage here (why do you think the WAMM is designed the way it is?); of the larger speakers I have reviewed recently, only the GNP Valkyrie, with its elaborate cabinet construction, developed a clearly superior sensation of width, depth, and imaging.
The bass of the IIID was surprising for a small loudspeaker. The lowest bass was, as you might expect, well down in levelno IRS challenger herebut there was a sensation of low bass and no false mid-bass emphasis. Organ-music fans will miss the bottom-end weight and reach of larger systems, but percussive bass, down to about 50-60Hz, was surprisingly satisfying, with good impact and dynamics (footnote 4). The woofers did appear to flop around rather alarmingly, however, in response to infrasonic signalslargely from analog discs. Although I encountered no audible woofer overloading, the IIID's ability to play at high levels without serious audible distress may tempt some to exceed its deep-bass power-handling capability; in such a situation I would recommend the use of a good infrasonic filter. Poor woofer loading at very low frequencies is characteristic of all ported systems.
The IIID had a distinctly up-front, lively sound, a gutsy quality that many audiophiles may, on first hearing, find to be too assertive. Given the need to make a choice, I have been biased in the past toward a more laid-back quality, but found the balance of the IIID easy to adjust to. I'm ordinarily wary of possible colorations in what I judge to be a forward-sounding loudspeaker. I did notice some reduction in midband clarity on complex program material, especially at high levels, a problem I would judge to be a tradeoff for the slow-slope crossovers used (the woofer still has substantial output up to at least 4kHz). However, this was not obvious on most program material played back at "reasonable" levels.
My rather rudimentary measurements indicated that the latest IIID had a very smooth frequency response. My own measurements were, in fact, flatter than Siefert's own published curve. I would tend to believe the latter to be the more accurateits linear but slightly elevated response in the 500 to 1000Hz region (up about 3dB) correlates well with my subjective impressions of the IIID's overall balance.
At its list price of $599/pair, the IIID faces stiff competition, but offers a real alternative to a number of the slightly smaller mini-monitors. Most of these have a distinctly laid-back frequency balance, don't cope well with sound levels that the Sieferts sail through unscathed, and can't match the IIID's superior top end.
After living with the IIIDs for a few days, I began to appreciate what they could do. After a few weeks of switching back and forth between them and larger, more expensive loudspeakers, I don't think I would advise audiophiles to junk their Apogees, Acoustats, IRS or WAMM systems in favor of the Sieferts. The benefits offered by such systems just cannot be had on the cheap. Having said that, however, I found it easy simply to enjoy the music with the IIIDs, and to ignore the inevitable limitations of a small, modestly priced (by audiophile standards) loudspeaker. The IIID is an excellent speaker for its size and price; it is a very good one by any measure.Thomas J. Norton
Footnote 1: Two manufacturers currently using Dynaudio tweeters (the larger 28mm version) are Synthesis and Thiel.
Footnote 2: So-called slow-slope crossovers use 6dB/octave rolloffs for all crossover points, which is said to better preserve phase linearity. The desirability of such slopes (which also have disadvantages) is still hotly debated.
Footnote 3: Or even worse, the totally meaningless "beyond the state-of-the-art," which I've seen used in recent audio writing (not in these pages). You can advance the state-of-the-art; you can't exceed it.
Footnote 4: Stay tuned for the Siefert Subwoofer, which should be available by the time you read this.