Near full range BMR (Balanced Mode Radiator)

Hi All,

Something that night tickle your fancy,

images


In the next few months a very interesting driver will
become available from Wilmslow Audio in the UK.

Its a near full range BMR (Balanced Mode Radiator) :

http://www.music-line.biz/cms/fileadmin/pdf/wp_ovator_bmr.pdf

http://www.hificritic.com/forum/default.aspx?g=posts&t=469

Midband efficiency is not high, making bass driver choice and bass
loading type very interesting, there are lots of workable possibilities.

2x12" open baffle could be quite interesting.

Myself, I'm currently planning on building the TRK design.

/Sreten.
 
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It will be interesting to see how this turns out, it seems like an interesting variation of the "flat cone" drivers out there. I'm guessing that not letting it produce bass frequencies might be more beneficial at this stage while the technology is relatively new. They forgot to put damping material between the disk and the pole-piece, inside the voice coil area ;-)

Their bass driver doesn't seem radically different aside from the "de-modulation rings", which seem to replace copper rings in other woofers...?
 

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I notice a shade of the so called Dr. Carl Pinfold driver, a balsa flatcone diy contraption
described 'first in Wireless World and later in Speaker Builder around 1986. '
Eelco

Hi,

I remember that but it wasn't a BMR, intended to be pistonic.

Looked a bit like : (but will a full length magnet and voice coil)

This is a HARP (High Aspect Ratio Panel) BMR

harp_br_600x281.jpg


rgds, sreten.
 
sreten;

Is that picture of the new driver from HiWave? I know they have a few BMR drivers out now (HiWave: sensation innovation), but they're going to release some new models shortly. I believe those will include 3.5" and 6" round, as well as 2 oval ones that look virtually identical to what you posted.

I have a preliminary PDF of them, but it's too big for an attachment. If anyone is interested PM me and I'll send it to you.
 
The PDF's

Hi tJm,

Thanks for the info. The Hi-wave driver certainly looks very similar
to the CSS (Cotswold Sound Systems) driver, similar parameters.

Only thing I can say is the frequency response seems to include
BSC, whilst the CSS driver is (allegedly) flatter, other than that
the peaks and dips are remarkably similar.

Quoted masses and dimensions are near identical.

The graphs imply quite a big difference in sensitivity, but not the text.

I simply don't know if this is the same driver or not.
CSS call it the BMR85DD, made under licence by Tymphany.
Colloms says it the latest version of a number of versions.
Hi-Wave call it the HIBM85C20-4/DD.

Will PE be selling the HiWave driver ? Interesting .....

How have you obtained this information ?

rgds, sreten.
 
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Hi tJm again, Thanks for the info in the PM, Mangar is too expensive for me, rgds, sreten.

I don't think the CSS driver is going to be cheap, but the hi-wave one ?
A poor mans version of the "TRK" might be on the cards if PE sell it.
 
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I simply don't know if this is the same driver or not. CSS call it the BMR85DD, made under licence by Tymphany.
Colloms says it the latest version of a number of versions. Hi-Wave call it the HIBM85C20-4/DD.

I would guess they aren't the same. To the best of my knowledge Tymphany and HiWave have no direct working relationship, so the indication is each driver is unique to their respective company. Which is a good thing, IMHO; the more people making BMR's the better. I would love to be the first kind on the block to make a set of speakers using a BMR, so I would prefer to have multiple options to choose from.


Will PE be selling the HiWave driver ? Interesting .....
How have you obtained this information ?

HiWave hasn't come out and said that directly, but it will be "distributed in the same manner" according to them. Since PE sells a few of their small BMR's now I would assume they'll have the larger ones as well.
 
Hi tJm again, Thanks for the info in the PM, Mangar is too expensive for me, rgds, sreten.

Cheap? Definitely not, but very interesting. From the prices I've seen everything they make is quite expensive, so they're certainly out of my league as well.

I've never heard a Manger speaker before, so I can't even say whether or not they sound as good as all the techno-babble they use. But for sure I'd love to hear them because it seems like their MSW is a cross between an electrostat and a BMR (sort of), and I find that very intriguing.
 
I would guess they aren't the same.

Hi, that might be true, but they are certainly IMO made in the same factory, rgds, sreten.

(Or alternatively use common parts sourced from the same manufacturer(s) mostly.)

If PE do end up selling them, I expect a startling difference in the prices, for very similar.

Specifications may be smoke and mirrors, but the hi-wave appears to have built in BSC
for a small cabinet in its response, possibly only needing minor treble EQing for "FR".
The CSS unit looks more classically flat, needing some BSC correction.
 
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Hi,

A further aside is does the Cambridge Audio Minx have built in BSC.

The graphs in the paper certainly imply it does, for such a tiny speaker.
Or are the graphs for both speakers the drivers mounted in a large baffle ?
BSC is such a tenuous subject when dealing with published information.

(Except for Seas, who publish real responses in real cabinets mainly.)

rgds, sreten.
 
HiWave (formerly NXT) has the world-wide patents on BMR technology as it is the creator. Any BMRs being made will be HiWave or under licence from HiWave. Cambridge Minx uses the HiWave BMR as do the USB driven Ufi UCube and the Soundscience QSB. BMR is a HiWave technology - even the NAIM Ovator is a licenced product, see page 14 of this: http://www.hi-wave.com/resource/NXT_Annual_Results_2009_-_FV.pdf
 
HiWave (formerly NXT) has the world-wide patents on BMR technology as it is the creator. Any BMRs being made will be HiWave or under licence from HiWave. Cambridge Minx uses the HiWave BMR as do the USB driven Ufi UCube and the Soundscience QSB. BMR is a HiWave technology - even the NAIM Ovator is a licenced product, see page 14 of this: http://www.hi-wave.com/resource/NXT_Annual_Results_2009_-_FV.pdf

Interesting that. I thought NXT simply went out of business, I wasn't aware they had merely changed their name. Wonder why they bothered to do that; NXT had history and cache, whereas HiWave is completely obscure.

Either way, I still want to get my hands on those drivers. That might take a while though - the link you supplied to their 2009 financials shows the exact same picture HiWave is using today in the preliminary documentation for the new BMR drivers. Two years and they still aren't released? That seems a bit ridiculous to me.

Actually, come to think of it... perhaps that's why they changed the name in the first place. Based upon that 2009 financial statement it's quite apparent they were swimming in red ink, so maybe NXT ultimately went bankrupt. Could explain why it's taking so long to release the drivers.
 
This sounds really interesting, but the pricing link seems to be down :crying:

Does anyone know in what range the price was? Is this some super premium priced driver priced at $ 1000+ each or $ 200-300 ish?

My next and more important question is if the distortion performance is superior or inferior to normal cone drivers, for me they are only interesting if they have equal or superior performance, preferably superior. I mean, why buy an expensive driver if a cheap woofer with lots of cheap tweeters does the job better?

And lastly, anyone how is the dispersion pattern is backwards? I would use it in an open or no baffle speaker, so identical forwards and backwards dispersion would be ideal but somehow I doubt it would be that nice ;).
 
The BMR drivers (from Parts Express ship same day and come with 45 day money back guarantee. Free Shipping Available. Order free 10,000 product catalog.) that HiWave sell now are dirt cheap, so it seems logical to assume the new ones will be reasonably priced as well. I've been in contact with there VP of operations, and I didn't get the impression they were going to be exorbitant.

I think what's also safe to assume is that the rear dispersion pattern will be nothing like the front. Based upon the engineering involved it's probably not possible to make them even close, but that's purely supposition on my part.