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Coincident logo
  • Coincident Speaker Technology
  • 19 Strauss Rd. Thornhill, Ontario, Canada L4J 6Z8
  • Official website
  • iblume@coincidentspeaker.com
  • +1 905 660-0800
  • +1 905 660-1114


Equipment[add model]

Coincident manufactures or has manufactured the following equipment (click to expand models list):

Dynamic Speakers
Valve Amplifiers

General information [contribute]

Coincident web site (September 2000): The Coincident Sound We are often asked, "What do Coincident Speakers sound like?" Our answer, "We try our hardest to make them sound like nothing". The theoretically perfect audio component would sound like nothing. It would simply transmit the signal it is being fed with no alteration, enhancement, subtraction or distortion. Our goal with all Coincident models is for them to pass as much musical information with the least possible coloration. Coincident speakers do not editorialize or attempt to glamorize the sound. For example, there is no intentional boosting of the midbass to provide the illusion of more bass, nor the rolling off of the high frequencies to make the resultant sonics more pleasing. Coincident Speakers are designed to be as musically accurate as possible. We attempt to create an open window on the musical event, with nothing interfering between the music and the listener. Consequently, Coincident Speakers are very revealing of the musical source, the room in which they are placed and the ancillary components used. It must be emphasized that high resolution DOES NOT connote low musicality. On the contrary, the better a component is at revealing the information it is sent, the more accurate and by definition, the more natural it will be since it will closer approximate the live music listening experience.

Those seeking to replicate the thrilling experience of listening to live music will greatly appreciate the "Coincident Sound." Our reference standard is live music and our goal is to get as close to the sound of real instruments playing in a real space, as present technology will permit.


Coincident web site (September 2000): Coincident Speaker Technology was established by Israel Blume in 1993 for the sole purpose of creating a superior loudspeaker. Mr. Blume was ultimately dissatisfied with every loudspeaker he had ever owned or listened to. From the Quad ESL 63 to the Martin Logans, to Wilson Watts and almost everything in between exhibited sonic weakness that proved to be in the long term unacceptable.

Blume put his over twenty five years of audio and music experience to work to conceptualize a loudspeaker that would reproduce music with no obvious or distracting perversions. He understood quite well the inherent limitations of electrostatic designs, i.e. the need for a signal contaminating high voltage step up transformer, its low sensitivity and large size et al. At the same time virtually all dynamic systems possessed their own set of compromises, namely, slow transient speed, small image size, etc.

Therefore, a new loudspeaker combining the best sonic attributes of cones and electrostatics had to be created. A daunting task to say the least. The first loudspeaker designed by Blume was the Concentric Monitor and its companion subwoofer, the Super Bass Monitor.

What made this speaker unique was its cylindrical enclosure. Unlike conventional cabinets, the Monitor was constructed out of computer cut MDF concentric rings. The advantages of this design was that its structural strength was typically 15 times greater than a prism shaped enclosure and furthermore rigidity was equal at all points. The fact that the enclosure was round also meant that internal standing waves were dramatically reduced.

The Monitor also used the finest tweeter and woofer extant and in keeping with Blume's philosophy, the crossover was very pure and simple using only the finest tested components. Many audiophiles and reviewers such as Frank Doris of The Absolute Sound were of the opinion that the Monitor system was one of the finest loudspeakers ever produced. However, there were three factors Blume felt he had to address before he could find acceptance in the marketplace with his dream speaker. Firstly, it had to more accessible aesthetically (which many felt the cylindrical enclosure was not), secondly it had to be less expensive to build (the Monitor was exceptionally labor intensive) and finally the speaker had to able to be driven by single ended tube amplifiers (which the Monitor could not).

The result of two years of design work culminated in the development of the Troubador speaker. Using extensive computer modelling, Blume was able to duplicate the sonic properties of a cylindrical enclosure but with the use of non parallelled flat plane walls. The most significant advantage of this type of enclosure is the elimination of internal standing waves.

Three types of standing waves affect all previously manufactured loudspeaker enclosures. The first and most powerful is the axial standing wave. The axial wave involves only two enclosure walls that are parallel to one another. Next in order of strength is the tangential standing wave which involves four enclosure walls that are parallel to one another. This type of standing wave has only half the energy of an axial wave (3db down). The last and least powerful standing wave is the oblique which involves six enclosure walls and it has only one fourth the energy of the axial wave (6db down).

How do standing waves degrade the performance of loudspeakers? A sound wave has a positive portion starting at 0 degrees to 180 degrees and a negative portion starting at 180 degrees. If the positive portion of the wave (i.e. compression) meets the negative portion (i.e. rarefaction), then the waves will combine and will be out of phase relative to each other. Likewise, if the positive portion of the waves meets another positive portion of the wave then the waves are in phase (i.e. the waves reinforce each other) the sound will be inordinately loud (i.e. the high pressure zone). Likewise, at locations in the enclosure where the sound waves are out of phase (one being negative and the other being positive) the sound waves cancel each other out and no sound will be heard (a low or no pressure zone).

The sonic result is uneven, boomy or sucked out bass response. The patented (#2157518) AWE (asymmetrical wall enclosure) eliminates the sonically deleterious effects of standing waves

In a further attempt to eliminate the sonic contamination of loudspeaker enclosures, Blume uses enclosure tuning techniques. Instead of using resonant enclosure materials and then attempt futilely to damp them out, all Coincident enclosures are constructed from inherently non resonant materials that need no damping. The enclosures are then tuned to a high fundamental resonant frequency that is sonically undetectable.

The culmination of this arduous, painstaking journey has yielded a series of loudspeakers that offer unprecedented performance in each price category. From the Mini Triumph to the Conquest to the Millennium, Coincident speakers sound better and are better constructed than competing designs at the same price.

Designer Israel Blume has recently realized his goal of building a true reference speaker that encompasses all the criterion he initially enumerated. That speaker is named the Millennium. This speaker is the most musically authentic loudspeaker in existence. It is capable of reproducing the musical signal fed to it with such verisimiltude that even a short audition will demonstrate this claim.

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