enjoyable listening experience. Imagine having a private command performance in your own listening room by your favorite singer or pianist or jazz trio, or even orchestra or opera company. That's what this Osborn can give you.
     Speakers can be roughly classified into two groups: those that transport you to the recording venue (you are there), vs. those that bring the musicians into your listening room (they are here). This distinction also affects the stereo imaging characteristics of a speaker. This Osborn belongs to the latter group, and only you can say whether this suits your listening taste and listening room parameters. On those recordings that are closely miked (and most are), the Osborn can be superb at projecting the musicians' presence onto a stage in your listening room. And then on those recordings that are distantly miked, which include a lot of concert hall ambience, this Osborn still brings the music into your listening room, and also brings the concert hall ambience along. In other words, this Osborn is so superbly transparent that it reveals all the information in a recording, including the concert hall ambience if the recording was miked that way. But the Osborn's preference for projecting music means that the concert hall ambience itself gets projected into your listening room and portrayed on a stage in front of you. There's a rich, wide stereo stage portrayed by this Osborn, and this stage includes rich concert hall ambience when that ambience is included in the recording. But there's still a sense that this stage, even with its concert hall ambience, is in your listening room (they are here instead of you are there). If you have a large listening room (which you would want anyway to suit any large speaker system), then having a full concert hall stage cum hall ambience projected into the same room with you can be exciting, adding a visceral charge to those tutti climaxes. But perhaps in a small listening room this experience might be overwhelming.
     Even though the Osborn's two main drivers are close together, thereby producing this Osborn's superb integration, these two drivers are still located on a large front baffle, and there is no anti-diffraction felt blanket on this large front baffle. Thus, there is necessarily considerable secondary diffraction radiation, some with long time delays, from the large, long, distant cabinet edges. This secondary radiation slightly impedes the ultimate stereo imaging capabilities of this speaker, by allowing the listener's ear/brain to cue in on the speaker location. This Osborn is excellent at portraying a wide, rich stereo stage, but the speaker's location can still be aurally detected within the stereo stage; it does not aurally disappear as well as mini-monitors can. Also, the Osborn's two main drivers are not phase aligned (nor are they phase coherent), which might slightly affect the ultimate stereo imaging capability.
     Second, this speaker's low end bass is wonderful. Its reach is deep and powerful, as it should be in every large speaker system. But it also has a special quality that is very rare, even among large high end speakers. This Osborn's bass has an easy flowing, wafting, rolling, relaxed quality. That's how real bass from real musical instruments really sounds, whether from pipe organs or plucked string bass. In contrast, most speakers, including most large ones, put out their bass with a forced, fiercely pumping quality. This artificial quality betrays the fact that these are merely cones flailing away, struggling mightily but vainly to reproduce the power of live bass - and in their straining they are unable to simultaneously reproduce that quality of flowing ease that live music's bass naturally has. This Osborn captures that special quality of live music's bass, and therefore sounds more natural and real than most other speaker systems.
     Third, for some listeners this Osborn's rich warmth might be too much of a good thing. We enjoy this speaker's rich warmth as musically natural, and we also find that this rich warmth helps to counterbalance the very revealing tweeter, helping to keep it from sounding too bright, analytical, or lean. But, at the low end of the 100-300 Hz warmth region, specifically around the 125 Hz crossover point, the warmth energy does get a bit too plummy. It is clear that the subwoofers are contributing a little too much energy at the crossover frequency (they are great below that). We found the same problem when we evaluated the add-on subwoofer system of the junior Osborn Epitome model, and the two subwoofer systems stacked in this Monument tower each appear to be similar to that Epitome subwoofer system. It might be possible for the manufacturer to address this by simply adjusting the value of the passive crossover components to begin rolling off the subwoofer at a slightly lower frequency, so it doesn't contribute quite so much at 125 Hz.
     This frequency of 125 Hz is also in a region where perceived energy is very dependent on other factors, such as the size of your listening room, the location within your listening room where you position this speaker, and your own listening position within the room. If your room is small enough to have a reinforcement room mode at 125 Hz, then this Osborn will energize this room mode very enthusiastically, and you'll have to employ countermeasures. On the other hand, if your room is large enough so that it does not have a reinforcement mode at 125 Hz, then you might be happy with the results. And, if your room is truly large, you could position these Osborns far enough from the back and side walls so that there is actually a partial cancellation null to these walls at 125 Hz.
     The subwoofer has its own dedicated speaker terminal at the back of this Osborn tower. Thus, you have various other options to tailor the sound of the subwoofer to your room and to your listening preferences. You could bi-amp the whole system, and then easily tailor the signal input to the bass amp to start rolling off at say 100 Hz, thereby decreasing the subwoofer's contribution at 125 Hz. Or, if you bi-wire the whole system (strongly recommended by the manufacturer), you could pad the wire going to the subwoofer with an inductor or resistor (this would degrade amplifier damping of the subwoofer, but that's not a big concern here since the huge magnets on the subwoofer drivers already tightly damp and control them). Or, if you really want to markedly knock down the plummy energy hump at 125 Hz, you could simply wire the subwoofer in reverse phase relative to how you choose to wire the main 2 way system (see below) when you connect the system terminals. This makes the subwoofer subtract from the 6 inch woofer/midrange around their 125 Hz mutual crossover, rather than additively reinforcing it (this would be an effective countermeasure choice if your room is small and has a reinforcement mode at 125 Hz).
     Fourth, the tweeter in the Grand Monument Reference (far more expensive than the tweeter in the Monument) is incredibly revealing, especially for a tweeter with such wide dynamic range and high power capability. But the laws of physics are cruel, and dictate that there can be no such thing as a perfect tweeter. If a tweeter's moving mass, including voice coil and diaphragm, are light enough to respond quickly, and thus be revealingly transparent and have extended treble response, then it will also be fragile and incapable of withstanding much heat, so it will be limited in dynamic range and will be unable to play loud (e.g. some silk dome tweeters that sound beautiful at low volume levels). On the other hand, if a tweeter's voice coil and diaphragm are made rugged enough to withstand wide dynamics and loud volume transients, to accurately reproduce the high crest factor transients of live music without compression, then they will be heavy, and that usually means lost transparency and less extended treble response (perhaps also with a response peak pushed down into the audible range).
     In short, two desiderata seem to be mutually exclusive opposites: you can have revealing transparency in a tweeter, or you can have wide dynamic range, but you can't have both. How then does this Osborn speaker manage the trick of delivering both mutually exclusive opposites from its tweeter? The answer again is big bucks. The manufacturer spends a preposterous amount of money on this one Audiom TLR tweeter driver for the Grand Monument Reference. And what this money chiefly buys is magnet, a giant magnet. This giant magnet manages to quickly accelerate and control the heavier mass of the tweeter's rugged voice coil and diaphragm, thereby restoring the desired quick response and excellent transparency. Thus, this Osborn speaker gives you a very rare best of both worlds in the treble: excellent transparency and quick response accuracy, combined with wide dynamic range and great loudness capability. It's a special treat to hear difficult musical instruments effortlessly and accurately (without compression) reproduced by this Osborn tweeter, instruments such as crashing cymbals or struck triangles. These difficult musical instruments humiliate virtually all other tweeters; lightweight tweeters compress the sound, heavy tweeters (e.g. JBL and Revel) sluggishly dull the sound, and EMITs go into paroxysms of frazzled distortion.
     Even this Osborn tweeter is not quite perfect, however. The response peak of its inverted metal dome has consequences within the audible spectrum. This puts a slightly bright, slightly hard edge on just the outline of treble transients. It's worth mentioning that the Focal tweeter used in some Wilson systems also has a response peak in the audible spectrum, and it too has very good transparency and dynamics. So this bright edge may simply be the small price we have to pay to the laws of physics, in exchange for getting the considerable sonic benefits of superb transparency plus wide dynamic range. The tweeter in the Osborn Grand Monument Reference gets much tamer after a thorough break in period playing music (or white noise), so you should not judge it fresh out of the box. After break in, if you still find this tweeter to be a little too bright, it would be easy to compensate for this with a judicious selection of associated components in your system. The Wilson systems are usually partnered with cables from Transparent Audio, which have a noticeable softening effect upon music's trebles, thereby taming the sound of the bright peak in the Wilsons' hard dome Focal tweeter. You could also experiment with adding more plush sound absorption materials to your listening room. Our preference is to employ maximally accurate cabling, so that we hear every wonderful tidbit of musical transparency from this amazing Osborn speaker. If necessary, we can adjust the room acoustics (using ASC Tube Traps) so that at least the reverberant room energy has a desirable tonal balance over the whole spectrum.
     But what about the direct energy radiated from the tweeter directly to the listener? How can you tame that while still using accurate cabling? See below.
     Fifth, this speaker's integration is excellent, especially for a large system, as discussed above. But its coherence is still not perfect. When this speaker system is connected as the manufacturer instructs, the midranges have a slightly phantom, recessed, soft quality. That's why this speaker, even with its vivacious and energetic musical projection, does not sound too aggressive overall. Its midranges, though adequate in quantity, are actually a bit too polite in quality (the opposite of the JBL forced presence syndrome). Furthermore, this phantom, soft quality in the midranges is at odds with the direct sound of the neighboring warmth and bass region on one side, and is also at odds with the direct, slightly bright and hard neighboring trebles from the tweeter. In other words, this speaker has a slight hole in the middle, with midranges that are slightly inconsistent in quality with the adjacent musical regions on both flanks. Again, this hole in the middle has nothing to do with inadequate quantity of midrange energy. It is a more subtle sonic phenomenon, having to do only with a slightly phantom quality to the midrange energy.
     What this means is that there is less than optimum coherence for the various parts of the spectrum. The bass and treble parts of the music sound pretty direct, with great tactile immediacy, whereas the midrange parts of the music sound more indirect and ghostlike. This is a loss of tactile coherence. It is most audibly apparent when, as often happens, a single musical instrument is playing a note with a fundamental in the midrange and with overtones in the treble. The fundamental will sound somewhat soft and ghostlike, while the overtones of the same note from the same instrument sound harder and more direct. This is also an example of loss of harmonic coherence, since the fundamentals and harmonics of the same musical sound do not cohere with each other.
     What's the reason for this less than optimum performance, in both tactile coherence and harmonic coherence? It's actually a common problem, endemic to most speakers. Once again, we're bucking up against the laws of physics. If a speaker system is to have wide dynamic range and good loudness capability, then crossover slopes steeper than first order are usually used, in order to protect the higher frequency drivers from excessive energy that would cause excursion distortion and/or burn them out. The problem is that these steeper crossover slopes introduce phase rotation and inversion. In the case of second order crossovers, such as used in many speakers systems including this Osborn, adjacent drivers are inevitably polarity inverted relative to each other (higher order crossovers introduce even worse phase rotations, with multiple inversions).
     This phase inversion is actually audible on most speaker systems. And, precisely because this Osborn speaker has such remarkable transparency, it reveals this common phase inversion phenomenon even more clearly than other speakers do. This extraordinary Osborn speaker reveals more of everything about the music, including the audible effects of the common phase inversion problem that it shares with so many other speakers.
     Inverted absolute phase polarity intrinsically sounds softer, more phantom-like, whereas correct absolute phase polarity intrinsically sounds direct, tactile, more articulate. To easily hear (and feel) this difference for yourself, say the word "puff" normally (correct polarity), and then say "puff" while you are continually sucking in air through your mouth (inverted polarity). The normal, blowing "puff" is positive, energetic, dynamic, direct, tactile, and articulate; the inverted, sucking "puff" sounds weak, withdrawn, softer, and phantom-like (it sounds like you're saying "beff" instead). Notice how even the initial "p" consonant sounds very different; the correct polarity, blowing "p" sounds like a sudden, popping, forceful explosion, whereas the inverted polarity, sucking "p" sounds very wrong, like a weak, tentative "b".
     When you connect this Osborn speaker as the manufacturer has made it (red post positive, black post negative), then the tweeter will be in the correct phase polarity (hence its direct tactile immediacy), but the adjacent driver (woofer/midrange) will be in wrong, inverted phase polarity (hence its soft, phantom quality). The crossover point between these two drivers is 3500 Hz, which is just the frequency region where the human ear/brain is most sensitive to all kinds of phenomena, including phase polarity. That portion of the music above 3500 Hz will be in correct absolute phase polarity, while the immediately adjacent portion of the music below 3500 Hz will be in the wrong, inverted absolute phase polarity. That region below 3500 Hz includes the lower midrange (300-1000 Hz) and midrange (1000-3000 Hz), which is why the midranges of this Osborn have a slightly phantom quality.
     Also, the midrange is where the heart of the melody is articulated, and because its quality is soft and phantomlike in this Osborn speaker, it can't effectively compete against the plummy warm 125 Hz hump from the subwoofer (discussed above), and so this shortcoming in incisive midrange articulation makes that 125 Hz hump seem even more overbearing. Incidentally, the woofer/midrange driver also handles the warmth region (100-300 Hz), so this region too is phase polarity inverted, but for these lower frequencies the sonic effects of phase inversion are less audible to the human ear/brain.
     Now, let's take stock of where we are. We have in the Osborn Grand Monument Reference a truly great speaker of enormous capabilities, but we also have found a few small areas where it is less than perfect. These less than perfect areas include the following:

1. tweeter a little too hard, direct and bright;
   

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