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BMR Units, Suitable for High Fidelity Speakers?

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pfm Member
Why is the build quality of BMR units so poor? I mean plastic baskets and the flimsiest of tabs for soldering the wires. And some high quality manufacturers used them in expensive speakers. I know very few audiophiles actually look at what is inside the cabinets but most high quality speaker companies that don't manufacture their own drivers almost always use drivers from highly respected makers with established names. Probably names you have heard of before for producing advanced designs with top materials and close tolerances. The BMR units I have first hand knowledge of look like they were designed, built and belong in computer or portable speakers.

Am I being too harsh here? Any thoughts?

Thanks!
 
The way they work using resonances imposes a limit on achievable technical performance somewhat below what can be achieved with multiple conventional drivers operated in manner to avoid resonances. However, the latter is going to be larger and more expensive which means wideband drivers of this kind may be a good choice at the budget end and in things like soundbars using lots of drivers. I believe the first examples from the likes of Cambridge Audio were budget speakers. The later use in audiophile speakers struck me as a bit odd and, at a guess, may have had more to do with distinguishing the speakers in the market place rather than anything to do with technical performance.
 
I've always wanted to have a listen/play-with the Manger design.

To be fair though, it's nearly 40dB£ more expensive than the average 'BMR' the OP refers to... :(
 
Rob used a BMR in the speaker he had at Scalford a few years back. There is a thread somewhere (probably in DIY). They were a two or three-way sealed BC1 sized box with an old AR 8” bass driver, a BMR handling most of the frequency range and (optionally) topped off with a supertweeter. They really sounded rather good based on a short listen.
 
I’ve heard the Manger driver a few times at shows. I really wanted to like it as I’m a huge fan of point-sources and not of crossovers, but I failed. There was always something very ‘dead’ about it. Just didn’t connect at all. I really didn’t like the Naim speaker that had something conceptually similar either.
 
h.g. said:
The Manger has been around for decades without picking up much of a following. They perform OK(ish) but generally below competent conventional speakers in the same price range. Some measurements and comparison here.
Click to expand...

Speakers I've heard which use the Manger have been some of the best I've heard at any price. Unfortunately they were makes I've never heard of before or since and possibly prototypes. All (both) were at Heathrow show about 2005 ish.
 
I stayed in a B&B in Huntingdon when I was consulting for Lola cars. One other regular occupant was a consultant who worked on the FE modelling of the NXT and BMR drivers and specifying and building prototypes.
He told me the difficulty with BMR drive units is manufacturing consistency since a surround which is fine for a mid range driver is nowhere near accurate enough for high frequencies, either dimensionally or consistency of damping. Since the BMR has to have a surround with enough travel for mid range it meant a substantial scrap rate and hand picking units for high quality.
I heard prototypes and they were amazingly good imo.
 
I've allways wondered if its the same BMR units in Naim Ovator's, Rega R10 and Cambridge Aeromax
Probably not, looking at prices
 
I remember going into Cyrus/Mission/NXT early in 2000 to sell their design guys expensive rendering kit. They were just punting their own floorstander with NXT at the time. Mediocre sounds.
 
Olsen said:
I've allways wondered if its the same BMR units in Naim Ovator's, Rega R10 and Cambridge Aeromax
Probably not, looking at prices
Click to expand...

IIRC yes they are the same or similar and from the same manufacturer (I've got all their bumpf and specs somewhere but can't even remember the companies name right now!)
 
Some comments by Overkill on Naim's exit from BMRs here:
https://www.diyaudio.com/forums/full-range/191853-near-range-bmr-balanced-mode-radiator-56.html

I heard Overkill's BMR line array with sealed subs a few years ago. Unfortunately I didn't get to try my own music, but it could have been one of the best systems I have heard. It certainly produced the most realistic replay of a drum kit I have ever heard, and by some considerable margin! I wish I had a copy of that recording.
 
Arkless Electronics said:
IIRC yes they are the same or similar and from the same manufacturer (I've got all their bumpf and specs somewhere but can't even remember the companies name right now!)
Click to expand...

It's Cotswold audio. Just down the road from me. I've been to the owners house who uses a line array with the smaller of the drivers. The great thing about them is their radiation pattern which is near 180 degree across the use spectrum. I've listened to some prototypes by another company with a similar idea but a very innovative take on the suspension, they were pretty special but I do t think they will see the light of day.
 
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