Morrison Model 19.1 Overview

The Model 19.1 is the culmination of over 60 years of research and development starting in the 1950's with such venerable names as Brociner, Voight, Lowther and Hegeman. The design goal is now and always has been to recreate the illusion of a live un-amplified musical event in the listening room. The Model 19.1 is a two way point source omnidirectional loudspeaker. The cabinet takes up less than a square foot of floor space and stands about 28 inches tall. It weighs about 50 lbs. The speaker is protected during shipping by a "hat" which clips on over the drive units. The passive external crossover is included to let the user get started on his musical journey. It is highly recommended that the speakers be bi-amped. This is done quickly and without fuss and bother since the woofer and tweeter have their own Neutrik Speakon connectors on the rear of the cabinet. The owner can quickly compare and realize the  advantages of active bi-amping with the standard passive approach in minutes.

The woofer drive unit is a custom built 180 mm design featuring the XBL2 motor structure. This allows a 32 mm peak to peak excursion. The magnet structure is shaded with shorting rings to reduce back emf and results in extremely low intermodulation distortion. The woofer has a very wide bandwidth to beyond 5 kHz with a gentle rolloff beyond. The rear wave of the woofer is loaded by a series of staggered length chambers which are sealed. This method of loading was used originally by Stew Hegeman in the 1950's and in the Morrison family of speakers since 1977. This loading concept reduces the usual large impedance peak at resonance to five very gentle humps. The impedance curve stays in a narrow strip from a minimum of 6 ohms to a maximum of less than 9 ohms. This turns a somewhat reactive load into a rather benign one. A rather happy circumstance for the power amplifier. A further advantage is that the woofer quickly recovers without overshoot when fed a pulsed signal, ie the woofer shuts up when the signal stops. The front face of the woofer is loaded by a 5 inch sphere parked just above the cone. This large "grapefruit" also acts as a dispersion plug for the woofer and as a housing for the tweeter. This allows the two drive units to be snuggled as close as possible to create the illusion that there is only one drive unit. Hence the point source. You can sit as close as 2 feet from the speaker and the ear cannot discern that there are actually two drive units. This can only be done when both drive units exhibit the same dispersion pattern.

The tweeter is a custom built 1 inch driver. It also features the XBL2 motor assembly. This allows for a longer linear throw, 2 mm versus the nominal 1 mm.  The resonance is low and the rear chamber is damped. The tweeter is crossed over at a lower frequency than is normal with a 1 inch dome without the usual penalty of distortion. The tweeter is housed in the top of the woofer's sphere and as a result it exhibits no diffraction problems - a major concern with conventional tweeters with a large flat faceplate. The front face of the tweeter is loaded and dispersed by a 1 inch sphere.  Overall we have a speaker covering the full frequency range with full half space dispersion. In other words, 360 degrees of solid horizontal dispersion and 180 degrees of vertical. Both drive units have identical dispersion patterns and both are optimally loaded. Both drive units launch their signals from the same vertical axis i.e.: at the same time. The result? A system which disappears in your listening room and leaves you in peace with the musicians.

Price: FOB Toronto US $ 7950 per pair.

 

Morrison Audio Model 41 Subwoofer

The Model 41 is a passive subwoofer.  It is built on the same platform as the Model 19.1 using the same woofer drive units minus the tweeter and associated parts. The woofer fires down to the floor on a short stand. This method couples the speaker to the room and has a 2 to 6 dB gain depending on room location. A solid state amp should be used for best results along with an active crossover. 50 hZ with a 24 dB / octave slope when used with the 19.1's or the crossover point can be shifted to 80 hZ when using smaller main speakers. Two Model 41's give optimum results as they can be moved around the room for flattest response.

Price: FOB Toronto US $ 4950 per pair.