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The Harbeth Monitor 40

If time-tested tradition is important to you, the Harbeth M-40 will have a leg up right from the start. It is largely an improved descendent of the BBC LS 5/8 and, more so, the Spendor BC-3 dating from the mid 1970’s. Well in the grand tradition, and veddy British.

It should be mentioned up front that the M-40’s have been replaced by the M-40.1. According to Harbeth, the change was necessitated not so much by any pressing need to improve the speaker, but by the original woofer being discontinued. At the same time, the midbass was tamed a bit, to make the speaker a bit more friendly to typical domestic rooms and the midrange driver changed to the newer Radial2 material, which should also be an improvement (in theory). I haven’t heard the new version, but according to word on the street, it’s better but not wildly different. So assume the new version is somewhat better than my review indicates.

These are relatively large stand-mount speakers and are not of a style that is currently in fashion, being wide and chunky. I like their purposeful look, but many may not. At any rate, the wide baffle is integral to their performance. All and all, a well thought out design where form follows function.

No discussion of Harbeth would be complete with out a discussion of Radial material and owner Alan Shaw. The Radial material is their trump card. Developed by Harbeth, its successor (Radial2 material) is employed as cone material in all their current speakers, as the midrange driver of the M-40.1 and the woofers of the rest of their line. It is well suited to the purpose. It has low coloration compared to most of the plastic and paper woofer/midranges generally found in contemporary speakers and its only current competition as a low coloration cone material may come from some of the recent high-tech sandwich cone materials now available.

It’s pretty apparent that Alan Shaw is the main auteur of the Harbeth designs, being responsible for the design and voicing of the line. Actually, he might object to the term voicing, since his goal is a speaker largely without “voice”, one that substantively reproduces the signal applied to its terminals. He has succeeded to a great degree and I suspect what you will hear is his personal philosophy on how music should best be reproduced.

These are relatively large stand-mount speakers and are not of a style that is currently in fashion, being wide and chunky. I like their purposeful look, but many may not. At any rate, the wide baffle is integral to their performance. This is a well thought out design.

There performance is from the general “reproduce the recording” school. You won’t find the expansive images or enhanced sense of image height that planars provide (or some of their coloration, either). You will get the sense that what you are hearing is generally what is on the recording, but with some alterations relating to how recordings tend to be made and the characteristics of real-world rooms.

Most of these deviations are intentional. The transition from the midrange to the treble tilts down a bit, not a bad choice considering that most recordings are made up close and can easily become bright sounding. And the midbass to bass transition has a bit extra, again not unreasonable considering the effects of floor bounce (but see my article “John Dunlavy and the Room” for more on this). In many rooms, depending on your point of view, this may result in a pleasing sense of warmth or a bit of a plodding bass (I come down on the side of the warmth, myself).

There are also some unintentional things, mainly a bit of congestion from the cabinet. As well tuned as its “lossy design” is, its effect can be heard as added thickness on some instruments and male voice. But I think it’s not severe and can be safely filed under the category “nothing’s perfect”. Many other speakers have cabinets with effects much worse and further up in frequency where those effects are more noticeable.

Listening to a few of the Mercury Living Presence series recordings, the somewhat forgiving top end of these speakers did not invite them to produce ear-biting strings. The Merc’s treble emphasis is less in evidence on the Decca/Fruhbeck de Burgos Albeniz Suite Espanola. In either case, the imaging was good if somewhat limited in height and depth and the tonality quite fine.

The vocals on the SACD of Beck’s “Sea Changes”  track “Already Dead” were commendably smooth and the guitars tracked in both channels rang out convincingly if with out the very last word in transient attack. Pink Floyd’s “Echoes” also came through beautifully but, in my view, suffered somewhat from the smaller soundstage that the M-40’s (and, to be fair, most other cone/dome/box speakers) produce. Here a planar can produce a more etherial sound that, to me, is more appropriate to this atmospheric piece.

As associated equipment, I used the Lectron JH-50 (tube) and the Electrocompaniet Ampliwire  (SS) amplifiers and the Motif MC-8 as preamp. For vinyl playback, the Goldmund Studio TT with Well Tempered Arm and Clearaudio Goldmund cartridge was employed. The Ampliwire usefully controlled the bass better, but the JH-50 sounded a bit better overall with a bit more flow and beauty. But overall, both circa 50 watt amps handled the speaker well and the difference in amps was more a difference in “seasoning” rather than any fundamental difference. I suspect that the M-40 would respond to even better amps in kind.

Of course, the Harbeths M-40’s were not cheap and the new 40.1’s are now priced at almost $13,000 (and require stands). But in my view, these are one of the best speakers that espouse their philosophy of music reproduction and one of my personal favorites (For whatever THAT’S worth…). They are what I call an “accountant audiophile” type of speaker, taking only a few liberties and producing a sober, predictable sound that, while it may not completely spark the imagination in the short-term, provides much of the inherent beauty of music in the long.


Floor Bounce and the messy world of home audio

The late John Dunlavy was castigated on another site for a) being concerned with phase response in his speakers (which I won’t deal with here) and b) not compensating for the “usual” floor bounce (by introducing deviations from anachoically flat in his speakers through the affected range). The purpose here is not to defend Dunlavy particularly, but to look at just one of the many phenomena that affect home music reproduction.

Floor bounce is caused by the sound that bounces off the floor between the listener and the speakers being out of phase at certain frequencies (usually between 100 and 300 Hz.) and partially canceling the direct sound, causing a dip in the frequency response at those frequencies.

Dunlavy’s argument here was that the floor bounce is present in the concert hall so it should be at home, the counter argument was made that the floor bounce is already present on a “properly made recording”, so the floor bounce at home would be double compensation. Sounds reasonable but…

Let’s look at how recordings ARE made rather than how we might WISH they were made. Generally, they employ a) a few mics high in the air and fairly close to the orchestra or b) a bunch of mics quite close to the musicians or c) direct feeds off of musical instrument amplifiers. So they are either far from hall boundaries or very close to the musicians. Given this, it’s safe to say that not much floor bounce is actually caught by the recording mics.

So, if “concert hall realism” is our goal, leaving the bounce in could be seen as necessary to compensate for the missing bounce (as related to a listener’s experience in a hall) in most recordings. So Dunlavy, in that sense, might have been right!

Of course, when we invoke “concert hall realism”, the can is open and the worms are crawling all over the room. Where in the concert hall? Some people like to sit mid hall, some in the back, some in the balcony and some in the first few rows. The sound is quite different, though that is partially compensated for by the fact that it is a live concert and wherever you sit, that comes through. And, on point with floor bounce, that also changes at different location in the hall. How do you compensate for a moving target?

Recording engineers (for various reasons) generally give us a quite close perspective on the orchestra. If the goal, rather than “concert hall realism” is to “reproduce what’s on the recording”, the close perspective is what you should hear, except on those relatively few recordings made from a more distant perspective. Interesting that many who espouse the “reproduce what’s on the recording” philosophy select and set up their speakers to eliminate the room as much as possible, buy a room compensation unit, but set that to a “target curve” rather than flat (now that flat at the listener is something we can accomplish). I know why they do it, and I don’t think it’s the wrong thing to do, but that’s not reproducing what’s on the recording, is it…

The point is that music reproduction in the home is a bit of a messy business and not as simple and obvious as we might like. We will look further into this as time goes on.

Bill L. and my AR3A’s

Two of my favorite people are Bill and Loretta Legall of MillerSound. Bill is one of the best when it comes to repairing and refoaming loudspeakers and is a knowledgeable and unassuming guy in general. One day I brought a pair of drivers for Bill to do his magic on when he excitedly told me that I had to hear a speaker he had acquired. But first, the story…

Bill and Loretta were driving around one day and cut into a neighborhood to escape some heavy traffic. In front of a house intended for the trash man was a pair of speakers. They looked rough and forlorn, but like seeing a bird with a broken wing or a wet, disheveled cat in the cold, Bill had to take them in.

Testing showed that, while the woofer foam had rotted out, the drivers were functional. But the rough cabinets were a problem, until Loretta remembered some matching veneer she had stashed away. Well, the woofers were re-foamed, the cabinets sanded and re-veneered, the crossover tested and capacitors replaced and a few other tweaks applied and it was time to listen to the new-old speaker.

“Kevin, you have to hear this, you won’t believe it”. So I entered Bill’s listening room to behold a speaker seemingly out of a time warp, a mint pair of Acoustic Research AR3A’s. And Bill wasn’t kidding, I didn’t believe it. Rich, beautiful music from a pair of speakers manufactured between 1967 and 1975 and rescued from the scrap heap. I realized immediately that this was a speaker that, like the Quad 57, Spendor BC-1, BBC LS3/5A and their ilk, ones’ knowledge of vintage speakers was incomplete without. So I asked Bill to look around for a pair for me (and I would look for myself).

A few days later, I got a call. “Hey Kevin, your AR3A’s are in” Bill had done it again, and I made arrangements to come by after work. When I got there, craftsman Bill had not only re-foamed the woofers, but refinished the cabinets and cleaned up the badges and, while they were not quite the thing of beauty that Bill’s pair are, they looked great!

Acoustic Research pioneered the use of the Acoustic Suspension loudspeaker which traded efficiency for deep bass from a small box and, in its day, the AR3 series was the biggest selling and arguably most successful speaker of its kind. The ascent of the Acoustic Suspension loudspeaker was helped by the ascent of the high power amplifier (a development necessary due to the lower efficiency of the newer design), which, depending on your point of view, led to a bright new future or consigned audio to a modern hell of inefficient speakers and high-powered solid state amplifiers. But that’s another story for another time…

So I have chosen the AR3A’s as my first speaker musing on Audiolog because a) I wanted to tell you a story about Bill and b) they are a classic and historic speaker that augured big changes in the audio marketplace in their day. There’s a pair on permanent display at the Smithsonian and not for nothing!

How do the AR3A’s stand up today? Well, certainly it’s a different kind of sound than we are used to. The treble is not exactly extended and the speakers do not have the level of detail we expect these days. The imaging doesn’t “do tricks” and there is a bit of residual roughness. You can hear the cabinets (not as bad as it sounds, they used ply rather than MDF back then). But there is plenty of bass compared to the typical bookshelf today and a generally warm, rounded sound that is simply more that the sum of its parts. You can hear what’s wrong, but the enveloping sound on classical is like a bath in warm Caribbean waters and the punchy sound on Rock and Roll gives you the feeling that this is how the musicians expected it to sound.

It feels almost wrong to pick the sound apart since it obviously wasn’t designed to cater to prevailing expectations, so I won’t. In my view, it was designed as a holistic unity and is unique to itself, I doubt anyone would design a speaker that sounds like this today and much is the pity. There is more than one way to skin the musical cat, and this is the current path less chosen.

But a music lover who is not a “hi end audiophile” could buy these, refurbish them and live happily ever after. Many did, back between 1967 and 1975…