Vintage Monitor Audio MA 4 Speaker (Closed)

Monitor Audio MA 4 specification :

Frequency response: 45-18,000Hz +2.5dB.
Recommended Amplifier Rating :15 watts to 75watts
Impedance: 8 ohms nominal.
Crossover: at 3-21cHz, basically 18dB/octave 9-element.
Sensitivity: 12 watts for 96dB at I metre.
Maximum level: 103dB at 1 metre.
Dimensions: 694 x 316 x 280rrun (23+ x 12+ x 11 inches).
Weight: 16kg (361b)

Review by JOHN BORWICK

            This is a two-way speaker design with a KEF B1039 220mm (8-inch) bextrene cone unit, crossing over at 3.2kHz to an Isophon 33mm (1-inch) tweeter with high power voice coil specially made for Monitor Audio. The main driver is centred in the bottom half of the cabinet and the bass reflex principle has been employed. The port emerges near the top of the enclosure and consists of a 50mm cylindrical duct extending about half way back into the cabinet. The dome tweeter is mounted very close to the main driver, which has advantages from the listening point of view. It is offset from the centre line, to the left in one speaker of the matched pair and to the right in the other.

           The review speakers were beautifully finished in teak veneer on all four sides and also the front, though this will normally be hidden by the grille cloth. This is of black material stretched over a chipboard frame having cutouts to clear the drive units and port. Six press-studs make a secure fitting on to the cabinet, which is sealed at all edges with the drivers bolted to the front panel. The rear face of the main driver magnet is pressed hard against a bracing board attached to the back panel and the whole enclosure has a thick bituminous lining to damp out panel resonances. There are foam pads to reduce standing waves and a loose roll of polyester wadding gives critical damping of the bass resonance.

             The musical quality from the MA4s was preserved up to very high sound levels and, by the time any harshness was introduced owing to overdriving, all sensible people would have said the music was already too loud for comfort. The makers quote a maximum sound pressure level of 103dB at 1 metre, which is very high by domestic listening standards. They recommend an amplifier power rating between 15 and 75 watts per channel. I would not quarrel with this, except to say that a 15-watt amplifier would have little power in hand to cope with transient peaks. I used amplifiers rated at 40 and 60 watts. The MA4 sensitivity is a little above average, one of the advantages of reflex loading over infinite baffles, and this helps to produce the wide choice of amplifier power ratings.In terms of directivity, the MA4s are no more or less problematical than most speakers on the market.

               To sum up, the Monitor MA4 speakers are well designed and handsomely put together. There are bigger (and better) loudspeakers but the sound quality is musically very satisfactory and this size is easily the most popular at present. I can visualize no problems of matching to a wide range of amplifiers—incidentally the 8 ohms nominal impedance is very nearly the lowest value at all frequencies—and room positioning should be straightforward, i.e. raised off the floor and preferably out a little from the corners. In money terms, the speakers represent above average value.

*These are the 1970’s originals and employ the very high specification KEF B200 - SP1039 bass/mid driver, the same driver found in the legendary KEF model 104 & 104aB*



Raj-0126657671

Original Pictures below :

up

bump

up

up

bump

up

bump

bump

up

up

bump

bump

bump

up

up

up

up

bump

bump

bump

bump

bump

bump