Thumbnail Filmstrip of Monitor 890 MK III Speaker Kit Images
Visaton Speaker Kit - Monitor 890 MK III
Art. No. 5957
Visaton Monitor MKIII - shown assembled with suggested cabinets, not supplied.
Characteristics and Sound Properties
It is well-known that there are two types of loudspeakers: hi-fi speakers that produce the most accurate, unaltered sound possible, and disco or musician's speakers, where the top volume level is of the utmost importance. These volume levels are normally only possible with horns but these often cause coloration of the sound. The MONITOR 890 MK III was designed specifically to combine the best of both worlds. In the mid-range, we use a driver & horn unit which is so dynamic and produces such undistorted music, that many a horn-disparager has had to admit that this is simply unbelievably "different". Two excellent quality woofers, TIW 300 - 8 Ohm, mounted in the 180 litre vented cabinet, generate a bass sound pressure that is physically tangible, as you have experienced with concert speakers. Combined with the first-rate TL 16 H - 8 Ohm high-range horn, we have created a loudspeaker system that breaks down the previously unbridgeable barrier between the hi-fi and the professional speaker.
The output levels of the mid-range driver and tweeter can be adjusted to the requirements of the locale using output controls. We recommend, initially at least, the following level settings: tweeter: -4 dB; mid-range: -4 dB. These can, of course, be adapted to suit the specific acoustics in the room and personal preferences.
Thanks to the added impedance linearising unit in the crossover unit, the Monitor 890 MK III is now even better suited to use with critical amplifiers (e.g. tube amplifiers).
Extract from Image HiFi (MK II): "The Monitor 890 MK II deals beautifully with the full range even down to even low output levels provided the listening area is not too small. The excellent mid-range horn reproduces voices and non-amplified instruments beautifully without the slightest over-emphasis and right across the frequency range. The full range of tonal sophistication is remarkably well differentiated for a horn-based system, and this with a clarity and dynamism that is missing in less powerful drivers. We were pleased to find that, provided the output level is well chosen, the high-range horn does not stand out on its own as a fragment of the picture but blends in well to the impressive overall panorama." "This combination of pure power and sophisticated manners was what irresistibly attracted me to the Monitor 890 MK II." Verdict: excellent
Extract from STEREO (MK II): "... this chunky character pounds out bass levels that make a lot of other speaker systems look pretty puny. The sounds washed around our ears precisely but unmistakably and very powerfully. It was enough to make you wince. But this Visaton model does not overdo it. The bass production is well balanced against the higher ranges to produce a tidy overall picture where the bass does not have trouble keeping up. The high range retains an airy feel and is very clearly defined. The horn's response and depth of sound are excellent, and its spatial positioning is a dream."
"The Monitor system can produce disco music just the way the kids like it, can make the walls of your nearest castle vibrate with Pink Floyd or some good organ music and yet it is still a real treat to listen to a symphony on the same speakers. This precarious fine line between hi-fi and professional speaker system has been very well mastered." "Visaton's Monitor speakers are more than just a pleasant sensation. They combine the typical strengths of a horn system like sound pressure and temperament with such features as accuracy of depth and all-round abilities brilliant!" Verdict: excellent
Extract from Klang & Ton (MK II): Provided you have enough space and a very tolerant partner, we can warmly recommend this major contribution to the art of building speakers to every aficionado of lively guitar-based rock through to subtle and sophisticated rhythm & blues. Although the Monitor set-up is perfectly capable of reproducing classical musical and can cope with lower volume ranges, its strength is definitely in the excellent representation of live-sounding events, full of temperament and dynamism.
Technical Specifications
Rated power | 600 W |
Maximum power | 900 W |
Nominal impedance Z | 4 Ohm |
Frequency response | 30-35000 Hz |
Mean sound pressure level | 94 dB (1W/1m) |
Cut-off frequency | 800 / 7500 Hz |
Principle of Housing | Bassreflex |
Net volume | 180 litres |
Outer dimension height | 1070 mm |
Outer dimension width | 688 mm |
Outer dimension depth | 508 mm |
Frequency and Impedance Response
Frequency Response and Impedance Graph
Exploded Cabinet Drawing
Exploded Speaker Box Drawing
Assembly
This octagonal cabinet looks more complicated than it really is. All the chamfers are cut at 22.5° except two (at 45°). When you set up the saw, it is best to cut fractionally over 22.5° to ensure that, on the outside, all the chamfers are really airtight. First cut the required cut-outs in the boards, which have already been cut to size. The two circular ones for the bass loudspeakers, the square opening for the tunnel and the two for the level controller. Next, build the main body without the base and top. You will need plenty of sticky tape to hold the joints together when gluing the side panels. The parts for the tunnel, the four stiffeners on the side panels and the vertical stiffeners (50 mm wide) on the front baffle then need to be shaped to an exact fit. The base then has to be shaped to fit exactly in the completed main body, since it is hardly possible to build the body with millimetre accuracy. Next, glue the vertical stiffeners to the base and the stiffener between the baffle and the rear panel.
The top with its cut-out for the terminals for the high- to mid-range is then shaped to fit and glued in position. The two crossover circuit boards are attached to the rear panel opposite the lower bass speaker drivers. The wiring to the horns need not be heavier than 1.5 mm². From the terminals to the circuit boards and to the woofers, use wires with a cross-section of 2.5 mm².
The twin terminal unit for connecting the mid- to high-range horns is fitted in the square cut-out in the top. The two gold-coloured jumpers have to be removed to do this.
The mid-range horn is placed on top of the cabinet on its three straight-sided feet. The tweeter is mounted on the wooden base supplied and is placed on top of the mid-range horn, towards the rear. The position of the two horns is crucial to the acoustics and, for this reason, they should be positioned as shown in the drawings.
Internal Damping
See drawing below for suggested placement.
Component Parts List for Each Box - Supplied with Kit
The kit comes with all necessary components (see list below for one box), one set if the speaker is an each, or two sets for a pair, see price above for details.
Tweeter | TL 16 H - 8 Ohm | 1 pc. |
Midrange driver | DR 45 N - 8 Ohm | 1 pc. |
Adapter | AD 25 H | 1 pc. |
Horn | M300 (MDF) | 1 pc. |
Speaker stands | Beech waxed | 3 pcs. |
Woofer | TIW 300 - 8 Ohm | 2 pcs. |
Crossover | Monitor 890 MK III | 1 pc. |
Level control | LC 95 | 2 pcs. |
Terminal | BT 95/75 | 2 pcs. |
Damping material | Polyester wool | 7 bags |
Special wood screws | 5 x 30 mm | 16 pcs. |
Wood screws | 4 x 20 mm | 8 pcs. |
Countersunk screws | 3.5 x 25 mm | 8 pcs. |
Cable | 2 x 2.5 mm² | 3.5 m |
Cable | 2 x 1.5mm² | 3.5 m |
Speaker Cabinet Material List to Make 1 Box - Not Supplied with Kit
Parts for One Box (not supplied) | Size (mm) | Quantity |
Material: 19 mm chipboard or MDF recommended | ||
Top and bottom panel | 688 x 508 | 2 |
Front panel | 782 x 380 | 1 |
Rear panel | 782 x 280 | 1 |
Rear side panel | 782 x 283 | 2 |
Middle side panel | 782 x 150 | 2 |
Front side panel | 782 x 212 | 2 |
Sides base-reflex channel | 91 x 79 | 2 |
Top bass-reflex channel | 91 x 342 | 1 |
Brace | 80 x 294 | 4 |
Brace | 105 x 444 | 1 |
Brace | 100 x 782 | 2 |
Strip | 50 x 782 | 2 |
Base | 630 x 450 | 1 |
Optional Accessories | ||
Terminal | High-End Terminal | 4 pcs. |
Special wood screws | 5 x 30 mm | 24 pcs. |
Speaker Cabinet Dimensions
Loudspeaker Box Construction Diagram - all dimensions in mm.
Crossover - Supplied with Kit Already Assembled
Speaker Kit Crossover Circuit