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Product Review - Duntech Ambassador-XL Speakers; Floorstanding speakers - March, 1996

By Jeanne Fairbrook

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Duntech Speakers

Duntech Ambassador-XL Speakers; Floorstanding speakers; One 1" dome tweeter, two 6 1/2" mid-range drivers, one 8" low frequency driver; Frequency response 40 Hz - 20 kHz + 2 dB - 3 dB; Sensitivity 91 dB/w/m; Nominal impedance 4 Ohms; Size 48"H x 9 1/4"W x 14"D; Weight 114 pounds each; Price $3,000/pair (US); Duntech Audio Pty. Ltd., 30 Pambula Street, Regency Park, South Australia 5010, AUSTRALIA, Phone + 618-347-2666, Fax + 618-347-2607; In the USA: Northstar Leading the Way, Inc., P.O. Box 3763, Durango, Colorado 81302, Phone (970)-259-6722, Fax (970)-259-6727.

Wow! Another set of speakers that can be called "furniture". I guess the editor has decided to let me have the pretty ones. Duntech is located in Australia, a lovely country that I hope to visit one day. In the meantime, I am pleased to review speakers from "Down Under".

The Ambassadors were released in 1995, with the XL edition following shortly thereafter. We received the XLs in Mahogany Touchwood (see photo). This means that the finish is not really mahogany, but an incredible replica which is made from resin coats that are "rubbed" with a roller device to reveal the various layers. The result is a durable finish that won't split like real wood, but is beautiful. If I had not been told it was a resin finish, I would have thought it was the real thing. Even up close, it looks like real mahogany, except that there is no grain. This is the only noticeable difference. The front, sides, and back (1" MDF) have the touchwood finish, while the top is MDF finished in black. The bottom has an extended MDF platform, also in black. Two sets of gold-plated binding posts allow bi-wiring or bi-amping (tweeter separate from mid-range/woofer). The enclosure is sealed (no ports). Crossover is three way, with a crossover frequency of 8 kHz, 6 dB/octave between the mid-range drivers and the tweeter, and 500 Hz crossover frequency to the woofer, 12 dB/octave. The woofer is located on the side, in mirror image configuration (see photo), so that the speakers can be placed with the woofer facing away from the center of the sound stage, or towards it. The tweeter and mid-range drivers are mounted in time aligned fashion, with the tweeter behind the vertical plane of the mid-range. The front of the enclosure has felt attached, to minimize reflections from the enclosure as sound emerges from the drivers. The tweeter has an adjustable felt baffle (see photo) which can be pushed inward or moved outward so that it is flush with the rest of the baffle. It can also be removed entirely if desired. This allows fine tuning the high frequencies.

I listened to the XLs with a separation of about 8 feet, slightly toed inward. With the tweeter felt baffle removed, the highs were a tad harsh, but with the baffles flush, they sounded about right to my ears. Pushing them all the way in gave more high end detail, but I liked them best flush. In this setup, they sounded laid back in the high frequencies, with a forward mid-range, and tight bass. I could hear no chestiness with female vocals. The guys in the lab said they would have preferred deeper bass, but the XLs sounded pretty good in that area to me. I particularly liked being able to have a wide sound stage by arranging them with the woofers facing away from the center. They produced plenty of volume with orchestrals. It did not take much power to drive them. Although we tested them with high power monoblocks (575 watts rms/ch), their high sensitivity (91 dB/w/m) should be compatible with 50 watt/ch amplifiers.

The frequency response test results were as follows (1 kHz set approximately at 80 dB, grille cloth off, tweeter felt pad flush with mid-range driver felt pads, microphone on axis one meter from enclosure, horizontal with tweeter):

Frequency: 31.5 Hz 40 Hz 50 Hz 63 Hz 80 Hz 100 Hz 125 Hz 160 Hz 200 Hz 500 Hz 1 kHz 2.5 kHz 5 kHz 8 kHz 10 kHz 12.5 kHz 15 kHz 18 kHz
dB: 67.5 65.0 73.1 75.3 75.5 83.8 77.6 71.5 70.8 76.1 79.3 74.8 68.4 79.1 83.0 82.5 80.0 79.3


Many people these days are concerned about floor standing speakers not fitting into the room decor. The Ambassador-XLs will compliment the surroundings in any home, as far as I can see. They score high on looks, and have a full bodied sound that is adjustable in sound stage and definition. This is a strong plus for audiophiles who like flexibility. No subwoofer is required, unless you want to go to the lowest octave (20 - 40 Hz).

I recommend them highly.

Jeanne Fairbrook

Manufacturer Responds:

I would like to explain some apparent anomalies in the measurements presented at the end of the article. The two dips at 200 and 5 kHz result from measuring the loudspeaker output too close to the speaker. At 3.5 meters (11 feet 6 inches), the path length from each driver acoustic center to the listener/microphone is identical, and the outputs add correctly. I have included a table of measured SPL values at 3.5 under quaisi anechoic conditions (using the anechoic segment of a MLSSA time sample) and the near field sum of the two mids and the woofer taking phase and time delay into account. Thank you for taking the time to perform a careful assessment of our speakers.

Frequency: 31.5 Hz 40 Hz 50 Hz 63 Hz 80 Hz 100 Hz 125 Hz 160 Hz 200 Hz 500 Hz 1 kHz 2.5 kHz 5 kHz 8 kHz 10 kHz 12.5 kHz 15 kHz 18 kHz
dB: 66.5 70.1 74.4 77.3 78.8 79.6 79.8 79.5 79.2 80.5 80 80 81.5 82.1 81.3 79.5 79.7 78


Jack Davis
Duntech Audio - Research and Development Manager

Secrets responds further:

We agree that, especially for speakers with more than one driver emitting the same frequency band (in this case, there were two mid-range drivers), a far field response test should be done. However, keep in mind that such tests bring room effects more into play. Following is the response test performed with the microphone placed at 9 feet from the speaker.

Frequency: 31.5 Hz 40 Hz 50 Hz 63 Hz 80 Hz 100 Hz 125 Hz 160 Hz 200 Hz 500 Hz 1 kHz 2.5 kHz 5 kHz 8 kHz 10 kHz 12.5 kHz 15 kHz 18 kHz
dB: 81.8 71.1 65.3 82.1 88.4 82.9 75.6 81.4 85.0 80.5 81.4 75.5 80.4 78.2 82.8 80.3 79.7 76.5

One can see that there is just as much variation in response with the far field test, and that the dips have shifted to lower frequencies. Of course, this is a real listening room test, rather than a test using an anechoic chamber. We will include near field and far field response charts for all speaker tests in the future.

Secrets Staff


Copyright 1995, 1996, 1997 Secrets of Home Theater & High Fidelity
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