VMPS Ambience Tweeter Review

Add-on tweeters

In the Sixties I owned a pair of AR-3a speakers. They produced some of the best bass of their day and a decent midrange, but the tweeter rolled off considerably, giving them a somewhat dull sound. I bought a pair of add-on tweeter arrays for them that helped considerably. In the Seventies I owned a pair of FMI J speakers, on which the designer, Bob Fulton, had placed electrostatic tweeter arrays. Again, the add-on treble support helped impressively in extending the highs. Now, I own a pair of VMPS RM40 speakers that need no high-end extension. The tweeters already sound quite smooth, refined, and well extended. However, when I saw a few years ago that VMPS's owner and designer, the late Brian Cheney, offered a pair of add-on ambience tweeters for his speakers, I thought it only appropriate that I try them out.

Each tweeter unit is four-and-a-half inches square by one-and-a-half inches deep, with a built-in crossover, double-sided tape to secure it into position, and a pair of four-foot wires that connect to the binding posts of a person's main speakers. The crossover produces a steep slope beneath 7k Hz, with a top end that extends out to around 20k Hz. The units have no on or off switch, and the only way to control their output is by using a foam muffler over them. Also, while VMPS offer them for use with most of their own speakers, Brian tells me there is no reason why they can't be used with other, non-VMPS speakers as well.

In talking further with Brian, he said the idea was to experiment with the units. There is no absolute perfect placement for everyone. If you place them on the rear of your main speakers facing the back wall, they can increase the ambient sound of the high end. If you place them on the rear of the main speakers facing the side walls or if you place them on the sides of the main speakers facing outward, they can increase the width of the sound field. If you place them on top of the main speakers facing upward, they can increase the height of the sound field. And, of course, if you place them on top or on the sides of the main speakers facing forward, they can augment the sound of your main speakers' high end. Then there is also the matter of how high or how low you're going to position them on your main speakers. Whew!

Also, if you do decide to experiment with the placement, I suggest you keep the protective plastic strips on the tweeters' double-sided tape and use heavy-duty duct tape or Gorilla tape to fasten the tweeters to different locations temporarily. Once you fasten them permanently to the location of your choice, they could be a bear to remove.

Connecting the speakers takes a couple of minutes. After that, you're on your own. I took about an hour fussing with them, first positioning the tweeters on the rear of my main speakers toward the outside edge and facing the back wall, on the same level as my regular tweeters on the front. This seemed, indeed, to increase the sense of atmosphere and environmental impact of the high end. Then I moved them around a bit, facing backwards and facing the sides. In the end, I returned to my original placements, with the add-on tweeters not exactly firing toward the back wall since I have my main speakers toed in toward the primary listening position. So the add-ons actually fire at an angle toward the back wall.

Ultimately, did they make a difference? Did they effect an improvement? Yep, definitely. However, it was a subtle improvement, not a day-and-night improvement. Understand, if I were writing for a high-end journal, I'd probably say they made all the difference in the world and a person couldn't live without them. But I prefer not deal in black-and-white absolutes. The add-on tweeters make a small and pleasing difference, period, enough to warrant their use.

For me, in my listening room and the way I positioned them, the VMPS ambience tweeters slightly increased the sense of airiness in the high end, slightly increased the stage width, and slightly increased the depth of the sound field. OK, I can understand why the add-ons would increase air and width, but I still don't quite understand why they would increase depth, why the sound stage would now sound deeper. I suppose I should simply not question it and let good things be.

There was one thing, though: After a few minutes of early listening, I pressed my ear to one of the main speaker's built-in tweeters and then to the add-on tweeter behind it. The add-on tweeter sounded rougher to me, more spitty. However, after about eight or ten hours of continuous use, the add-ons seemed to smooth out and lose some of their initial grittiness. My advice: Let the ambience tweeters burn in for a while before judging them.

Nevertheless, I still hadn't convinced myself that the improvements I was hearing weren't imagination. If I were more clever, more inventive, or more ambitious, I might have rigged up an on-and-off device that I could use from my listening position. Being none of the above, I resorted to the next best thing: a pair of washcloths and the Wife-O-Meter. I used masking tape to fasten heavy washcloths over the add-ons tweeters, cloths that my wife could quickly roll up and place on top of the units so that within seconds she could either open up or dampen the tweeters' response. I had her do this a number of times while I listened from my preferred position in front of and between the main speakers. As you might expect, I heard the sound come more to life with the cloths removed, I heard more ambient air around the high end, I heard a wider stereo spread, and I heard greater depth to the sound field. Again, big differences? No, and they were differences that most people probably wouldn't notice without the dampening test. Indeed, they are differences some people might not discern even during the test. But I heard them, and I don't profess to have golden ears.

Now, to answer that question of whether they're worth it: Yes, for me the add-on tweeters were worth every penny of their $189 asking price, largely because I'm the kind of guy who is always trying to squeeze that last ounce of sound from my audio system without having to pay an arm and a leg to do it. The VMPS Ambience Tweeters afford me the luxury of slightly better sound at a modest cost. Seems like a deal to me, and if you can find a pair used, you might want to investigate them.

JJP