SpeakerTalk

[ColinR]

I've just conducted an internal examination of my Monitor Audio MA4's (1976 B200 SP1039) and MA5's (1977 B200 SP1014), each has modified Isophon tweeters and the crossovers are built on a common printed circuit board to the MA7. Does anybody know the MA7's specification?

[ColinR]

Those were series II's btw, the "originals" use the Peerless 10 HFC tweeter, like the MS-235's.

I've seen a pair of MA7's and they use Audax units.

The MA6, two varients KEF B200 plus Audax tweeter or two Audax units.

MA1 KEF B139B, B&W bass-mid, Peerless or Isophon tweeter.

MA3 some 14" by 9"eliptical unit not made by KEF, B&W bass-mid, Isophon tweeter.

The B&W bass-mid is the unit used in the DM4 btw.

[proffski]

If it is the same unit as used in the B&W DM3 then it was made by EMI.
B&W modified theirs slightly by adding extra mass to the cone, not far from the laminating by the dust cap.
The DM3 was larger than the DM4 and I am not sure if the bass units were identical.
The actual size quoted by B&W for the bass unit is 13.5 X 8 1/8"
Although EMI sold speaker units to the public this one was only for manufacturers.
The unit was also used in the B&W P2/H
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

[ColinR]

The unit was a 14*8.5" job with a plasticised cone.
Having seen one once, it had no markings and I cut myself on the poorly finished frame, so not KEF (poor finish, wrong magnet type), not EMI (different frame, poor finish).
So, maybe an Elac(?) who produced similarly sized paper coned units for the Lecson HL1.

The Lecson HL1 - two horn loaded bass units, Elac/IMF "knock-off" of the Peerles KO 40MRF and a dome twweter. Very efficient and very loud!

[proffski]

I love the efficiency of Horn Loading. But the colouration is a big no no!
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

[proffski]

Ah, the HL1, two 32 X 20cm bass and 125mm mid with 30mm HF.Crossover points at 840-4kHz.
£280 + VAT back in 1978.
I adore to this day their pre and amplifiers!
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

[ColinR]

Saw some MA2's recently. The design was very MA1'ish in shape, but the 8" bass and 4"mid looked like Dalesford units, tweeter Audax(?).

[Craigb]

Hi Colin, A few years since you placed this question so I have no idea if you have got your information. I found this thread while searching for something else. I've been reading a brochure I have of Monitor Audio range MA1, MA3, MA5, and MA7.

And it states the following:

"MA7 Compact reflect enclosure with units and crosover. One 6.5 inch bass driver; one myler 1 inch dome tweeter. Crossover 3khz.
FR 70 hz to 20 khz +/- 4db overall 40hz to 22khz
HC 25 watts programme
Minimum Power 8 watts
Impedence 8 ohms
Size 16 X 9 X 8 deep
Weight 15lbs

A highly compact system, this model could be regarded as a smaller but more efficient version of the MA5, possessing the similiar design concept of low colouration coupled with a clear and detailed sound."

However the MA5 is said to have a soft dome tweeter in the brochure but the MA3 a damped mylar 1 inch tweeter.

The only reference to KEF on the brochure was the B139 in the MA1s.

Incidently. I believe I have a pair of MA7s that I bought 30 years ago but until recently have not been able to identify.

Cheers Craig.