Dick Olsher Dahlia speaker J. Gordon Holt reviews

J. Gordon Holt reviews the Dahlia, from February 1986 (Vol.9 No.1):

Visibly, there is nothing to distinguish Dick Olsher's Dahlia design (see later) from hundreds of other small speakers—except, that is, that it's uglier than most such. Although our samples were superbly finished (Dick Olsher bought them from a professional cabinet maker), the enclosures' dimensions were apparently chosen according to acoustical dictates rather than aesthetic considerations. The resulting shape is rather squat, like a kneeling dwarf.

Since I haven't tried putting one of these together according to the instructions, I can't comment on its DIY aspect. Sonically, though, this is one of the most appealing small systems I have heard (footnote 1).

Sound Quality
Dick and I have done enough listening together for him to know very well what I like in a loudspeaker. From my gut reaction to the Dahlia's sound, I almost wonder if he didn't design the thing to appeal specifically to my personal taste. He assures me he didn't; that, in fact, he designed it to appeal to his own. Though DO and I often agree about reproduced sound, I didn't think we agreed this much! (On the other hand, Larry Archibald is also very impressed with the Dahlias, so perhaps DO is really on to something here.)

As DO frequently says in his reports on bookshelf systems, "Of course, there's no deep bass!" There isn't, and there isn't supposed to be. Friend or not, Dick cannot repeal the laws of physics: low-end range requires a large system. It is understandable that low end is the Dahlia's weakest performance area.

The Dahlia is designed to have a slight response hump at around 70Hz to balance out what would otherwise be a rather thin sound, but I couldn't confirm it. My checks with an oscillator showed a substantial hump at around 88Hz, and another of significantly lower amplitude at around 66Hz. (Neither frequency has a wavelength related to any dimension of my listening room.)

The system's low-end balance is optimized for placement away from room corners and a couple of feet off the floor. If they are placed below ear level, they should be angled upward to beam the enclosure axis at the listener's head.

Optimally placed, the usable low-end range of the Dahlia extended to around 35Hz, which is quite remarkable for any system this size, but the output at that frequency is enough below the midbass level that it does little more than add a small amount of foundation to the sound. Oddly, the pronounced resonances I measured in the midbass are barely audible, if at all, as either boominess or heaviness. In fact, the Dahlia is superbly balanced and has a remarkable (again, considering its size) amount of low-end weight. Kick drum, for example, sounds very quick and tight, and is completely free from overhang. Predictably, though, it is lacking in visceral punch.

Imaging is best with these speakers toed in to cross axes a little in front of a centrally seated listener. With that orientation, the listening area is about 6' across and, from any seat within it, the soundstaging and imaging are excellent in spaciousness and directional specificity. The soundstage is wide and deep, extending outward to beyond the loudspeakers. (I used to scoff at the impossibility of this; I don't any more.)

I consider the entire middle range to be just about state-of-the-art in neutrality and spectral balance. The system has no distinctly audible colorations, even with changes in listening height, and reproduces every musical instrument (including the large brasses, so often slighted) with a high degree of realism and accuracy. The Dahlia is very much what some of our writers call a "dynamic" speaker. Volume contrasts are well reproduced, without the compression exhibited by many much higher-priced speakers.

Overall, the Dahlia has very good detail and focus, with virtually none of the veiling and more or less subtle muddiness I find in an appalling number of much more costly cone systems. In these respects it rivals, but does not quite equal, the better full-range electrostatics.

One of the things I particularly like about this system is its high end, which has the kind of sweetness I hear in live music, but none of the dullness of many "sweet" loudspeaker systems. The high end on the Dahlia is balanced for fairly high-level listening, under which condition the extreme top is in perfect balance with the rest of the audio range. At lower levels, the high end is rather dull and closed-in. (This change has nothing to do with the speaker, but is related to our ears' tendency to roll off high end at reduced volume levels, footnote 2).

DO claims that his system has a maximum "pink noise" power handling capability of 50 watts, which I have no reason to doubt. But, unlike a lot of small systems rated at 100 watts and higher, the Dahlia's sound does not become increasingly hard or shrill at listening levels above 85dB. The Dahlia will play effortlessly at levels approaching 100dB, and I had the feeling it could have taken more.

Because the Dahlia is very neutral in terms of apparent listening distance, you can get practically any "listening distance," from close to distant, merely by judicious choice of power amplifier. I got what I judged to be the best overall sound with the Conrad Johnson Premier Five tube amplifiers, but then I tend to like a somewhat forward sound. Excellent, although slightly more distant (and spacious), sound was obtained from our Adcom GFA-555, just before one of the amp's channels died (it now appears that only an internal fuse went bad).

All in all, I liked so many things about the Dahlias that I felt no urgency to set them aside after testing. There are few small speakers I have felt this way about, and none cost as little as these (in DIY form). These would be recommended at $400 a pair. At about $200, plus a few hours' work, they're a genuine bargain.—J. Gordon Holt

Footnote 3: The following was written before JGH was aware DO's own feelings about the Dahlias.—Larry Archibald

Footnote 4: I question this dismissal (though JGH is, of course, correct in citing the ears' lower sensitivity to high end at reduced volume), simply because live music doesn't behave that way. A soft passage on an instrument with high frequency energy—a flute or piccolo, for instance—will not sound dull, merely soft. I think that one characteristic of the ideal music system, when we finally approach it, will be effortless change from soft to loud with no change in sound character or apparent realism.—Larry Archibald