Getting there....!
I am getting there!
Got a lot of activity in November and December so should be able to publish some accurate measurements to give all the graph guru's some Christmas reading....!
In the mean time I am getting great results with outdated, totally useless and irrelevant subjective tests...
At the end of the day I might have to build a model esp for the DIY graph geeks...It wont sound as good but its measurements will be fab so they can get the graphs silk screen printed onto grill covers and just stare at the graphs instead of listening to music...!!!
Jason Shep is going to pop over next week for a listening test (I know we must all totally ignore subjective test results....blah blah blah) so he will be able to report back his impressions as a totally independent reference.
Cheers
Derek.
I am getting there!
Got a lot of activity in November and December so should be able to publish some accurate measurements to give all the graph guru's some Christmas reading....!
In the mean time I am getting great results with outdated, totally useless and irrelevant subjective tests...
At the end of the day I might have to build a model esp for the DIY graph geeks...It wont sound as good but its measurements will be fab so they can get the graphs silk screen printed onto grill covers and just stare at the graphs instead of listening to music...!!!
Jason Shep is going to pop over next week for a listening test (I know we must all totally ignore subjective test results....blah blah blah) so he will be able to report back his impressions as a totally independent reference.
Cheers
Derek.
(lol) still looking forward to the off axis plots though...
I'll have to retract my words about good off axis performance of BMR's, as the next one in the same thread I linked to looks very well behaved!
http://www.diyaudio.com/forums/full-range/262391-tebm65c20f-8-bmr-driver-3.html#post4085530
And with a much more open basket on the back than the ferrite model(s) and 7 mm x-mech it looks very well suited to lines as well! Square shape, packed against each other... of coarse being that small gives up some lower frequencies, but with enough of them in a long line...
Wonder if it is a neo magnet though, I suppose they would have mentioned that if it were.
I'll have to retract my words about good off axis performance of BMR's, as the next one in the same thread I linked to looks very well behaved!
http://www.diyaudio.com/forums/full-range/262391-tebm65c20f-8-bmr-driver-3.html#post4085530
And with a much more open basket on the back than the ferrite model(s) and 7 mm x-mech it looks very well suited to lines as well! Square shape, packed against each other... of coarse being that small gives up some lower frequencies, but with enough of them in a long line...
Wonder if it is a neo magnet though, I suppose they would have mentioned that if it were.
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Difference of ratio of Xmax Vs Dmax...
waterfall of a 4.5 inch Neo BMR....
Here is a Waterfall plot that demonstrates the ultra clean and ultra fast settling time of a prototype 4.5 inch BMR.
Apart from the sub one millisecond settling time, a less obvious benefit of this particular driver is that due to its very even power response, one can use DSP / Eq to smooth the frequency response and maintain the balance....This is major!
Cheers
Derek.
Here is a Waterfall plot that demonstrates the ultra clean and ultra fast settling time of a prototype 4.5 inch BMR.
Apart from the sub one millisecond settling time, a less obvious benefit of this particular driver is that due to its very even power response, one can use DSP / Eq to smooth the frequency response and maintain the balance....This is major!
Cheers
Derek.
I am very much looking forward to hearing these,at this point they almost seem to good to be true !
I had been thinking about a full range driver for midrange/highs as a point source but hadn't even considered using as a line array,very exciting
I visited Derek yesterday & had a listen to his BMR line arrays
Thank you very much Derek
Most listening was done with flac files from a laptop sent to a modest Yamaha AVR via an inline usb to optical widget,the BMR arrays were crossed over to a pair of woofers (as this is how i'll be using them)
I was extremely impressed,very dynamic,the sound hit hard like real instruments do,very smooth & natural,off axis sound is superb.
I expected vocals to be a strong point,not having a crossover & blend of dome/cone in the 1.5-4khz region is obviously a big advantage,the BMR's were outstanding with vocal quality,sounding totally natural to me & projecting nicely.
The top end sounded very refined,maybe a little soft compared to what i use as my reference (Steinway Lyngdorf,with AMT tweeters) but considering it was coming through an AVR i expect it to sound much more open through my Lyngdorf TDAi2170.
I bought 8 drivers to make a little pair of 4 driver onwalls for evaluation,construction of (rough) cabinets is underway so i'll report back once i get them running
I visited Derek yesterday & had a listen to his BMR line arrays
Thank you very much Derek
Most listening was done with flac files from a laptop sent to a modest Yamaha AVR via an inline usb to optical widget,the BMR arrays were crossed over to a pair of woofers (as this is how i'll be using them)
I was extremely impressed,very dynamic,the sound hit hard like real instruments do,very smooth & natural,off axis sound is superb.
I expected vocals to be a strong point,not having a crossover & blend of dome/cone in the 1.5-4khz region is obviously a big advantage,the BMR's were outstanding with vocal quality,sounding totally natural to me & projecting nicely.
The top end sounded very refined,maybe a little soft compared to what i use as my reference (Steinway Lyngdorf,with AMT tweeters) but considering it was coming through an AVR i expect it to sound much more open through my Lyngdorf TDAi2170.
I bought 8 drivers to make a little pair of 4 driver onwalls for evaluation,construction of (rough) cabinets is underway so i'll report back once i get them running
Good to read you liked the BMR arrays from Derek.
Be sure to build/make a modular cabinet for the 4, so you can add to it later
.
Good to read you liked the BMR arrays from Derek.
Be sure to build/make a modular cabinet for the 4, so you can add to it later
Thank you,thats very good advice,although if i like the results & as i won't need them to produce any bass,i may ultimately go with the silk surround versions
Hi Derek, is this a different driver to the 500 you bought a year or 2 ago?
Also I would welcome your thoughts....
I am considering a new project with BMRs, along the lines of 2 BMRs facing each other with a Duevel type reflector in between them. The idea is to produce an omni-directinoal sound (albeit only true in a horizontal plane around the height of the reflector). Do you think 2 pcs of the 4.5" Neo driver are man-enough for this application if crossed over to subs using an electronic crossover with 2LR @ 120Hz high pass response (ideally the BMR speaker should have its own 2nd order rolloff @ 80Hz, then it will play nicely with my LF crossover slopes).
Do you still have BMRs for sale?
Thanks,
Dave
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BMR options
Hi Dave,
Interesting idea trying BMR's in a Duevel configuration....I can only suggest you hear what a pair of my BMR's can do in a conventional free standing or on wall configuration to give you a reference to aim at.
I am currently listening to a sweet two driver combination of a rubber surround BMR and a silk surround....Crossed over at 80 Hz to a pair of subs they are singing beautifully!
Regarding the drivers them selves, I have finally reached my goal of developing a double roll silk surround version as well as a rubber surround version....My 2015 drivers are far superior to my 2012 drivers.
If you email me, derek@custominstallaudio.com
I will send you a DIY guide to cabinet construction, Q, loading etc.
At the moment I only have some rubber surround BMR's available, happy to demo them as well.
All the best
Derek.
Hi Dave,
Interesting idea trying BMR's in a Duevel configuration....I can only suggest you hear what a pair of my BMR's can do in a conventional free standing or on wall configuration to give you a reference to aim at.
I am currently listening to a sweet two driver combination of a rubber surround BMR and a silk surround....Crossed over at 80 Hz to a pair of subs they are singing beautifully!
Regarding the drivers them selves, I have finally reached my goal of developing a double roll silk surround version as well as a rubber surround version....My 2015 drivers are far superior to my 2012 drivers.
If you email me, derek@custominstallaudio.com
I will send you a DIY guide to cabinet construction, Q, loading etc.
At the moment I only have some rubber surround BMR's available, happy to demo them as well.
All the best
Derek.
Hi Derek,
please elaborate on the differences between the rubber surround & silk surround models,we touched on it when i visited you but time was short & there was lots of info i was trying to take in !
If they are better in the mids/highs than the rubber surround models i heard at yours then they must be very special indeed
please elaborate on the differences between the rubber surround & silk surround models,we touched on it when i visited you but time was short & there was lots of info i was trying to take in !
If they are better in the mids/highs than the rubber surround models i heard at yours then they must be very special indeed
Hi Derek,
Very interesting indeed!
I have sent you an email.
Best regards,
Dave
Silk surround BMR Vs rubber surround BMR
Hi Jason,
Compared to the single roll rubber surround BMR, the double roll silk surround BMR has a lower Mms, a redesigned bending mode counter balance structure and different damping compounds applied to the cone and spider.
The TS parameters of the silk surround version have been optimised for a Q of 0.707 Q in 2.4 Litres of air and to work with sub woofers or bass drivers crossed over between 60Hz to 160Hz Hz.
The result is indeed quite remarkable....A clear improvement in all areas of performance, both subjective and measured..... The most dramatic of the improvements can be seen in the waterfall plots.
The rubber surround BMR manages a superb 3.5 Milliseconds settling time which is way ahead of any conventional push / pull wide band driver and actually still much better than most specialised midrange drivers.
The silk surround version settles in just under 1 Millisecond....Astonishing and unique....Clearly audible with a pristine believability that is captivating me hour by hour.
As I type this I am actually listening to a pair of twin drivers ( one silk & one rubber surround) with Zero Eq and no subs....Honestly, I keep shacking my head in disbelief....Then I add in the subs and just giggle out loud ....You need to come and hear these!!
All the best
Derek.
Hi Jason,
Compared to the single roll rubber surround BMR, the double roll silk surround BMR has a lower Mms, a redesigned bending mode counter balance structure and different damping compounds applied to the cone and spider.
The TS parameters of the silk surround version have been optimised for a Q of 0.707 Q in 2.4 Litres of air and to work with sub woofers or bass drivers crossed over between 60Hz to 160Hz Hz.
The result is indeed quite remarkable....A clear improvement in all areas of performance, both subjective and measured..... The most dramatic of the improvements can be seen in the waterfall plots.
The rubber surround BMR manages a superb 3.5 Milliseconds settling time which is way ahead of any conventional push / pull wide band driver and actually still much better than most specialised midrange drivers.
The silk surround version settles in just under 1 Millisecond....Astonishing and unique....Clearly audible with a pristine believability that is captivating me hour by hour.
As I type this I am actually listening to a pair of twin drivers ( one silk & one rubber surround) with Zero Eq and no subs....Honestly, I keep shacking my head in disbelief....Then I add in the subs and just giggle out loud ....You need to come and hear these!!
All the best
Derek.
Silk drivers available in Dec / Jan
Hi Jason,
I have some silk drivers on order, due in Dec, hopefully before Christmas.
My priority is building the demo speakers for my CIA business.
I have several studio monitors to build plus a few high end home cinema designs that all must be completed by Feb.
Once I have done a demo tour and got the sales started I will be in a better position to look at the stock availability as this is a very specialised driver and I am looking at 14 to 16 week lead times!
As per my DIY construction guide I send out, the silk drivers will only be available as part of a fully designed kit, not as a driver only purchase.
Cheers
Derek.
Hi Jason,
I have some silk drivers on order, due in Dec, hopefully before Christmas.
My priority is building the demo speakers for my CIA business.
I have several studio monitors to build plus a few high end home cinema designs that all must be completed by Feb.
Once I have done a demo tour and got the sales started I will be in a better position to look at the stock availability as this is a very specialised driver and I am looking at 14 to 16 week lead times!
As per my DIY construction guide I send out, the silk drivers will only be available as part of a fully designed kit, not as a driver only purchase.
Cheers
Derek.
Hi,
I need some very shallow drivers for surround duties in a narrow home cinema room, so was looking at FR drivers, but these look intriguing - how would a single driver (like the one from RS) do if the listening distance of a row of people was between 2 to 7 feet? With them crossed to a sub at 80hz, think they would be able to keep up with 'normal' speakers considering the wattage differences (though surrounds don't get used that much compared to the LCRs). Or would 2 work better?
Cheers
Gary.
I need some very shallow drivers for surround duties in a narrow home cinema room, so was looking at FR drivers, but these look intriguing - how would a single driver (like the one from RS) do if the listening distance of a row of people was between 2 to 7 feet? With them crossed to a sub at 80hz, think they would be able to keep up with 'normal' speakers considering the wattage differences (though surrounds don't get used that much compared to the LCRs). Or would 2 work better?
Cheers
Gary.
RS BMR's fine for surround duties
Hi Gary,
To be honest at the incredible low price the RS BMR's are great value and I would recommend them for rear speakers or background music.
I would be tempted to buy 4 or 8 of them and run them as pairs or 4's per channel, this will greatly improve the sound quality as the cone displacement will be halved ( two drivers) or quartered ( 4 drivers) per side.
I am traveling until next week so only on my phone but once I get back to base I can send you some info if you PM me with your email.
Hope this helps and all the best
Derek.
Hi Gary,
To be honest at the incredible low price the RS BMR's are great value and I would recommend them for rear speakers or background music.
I would be tempted to buy 4 or 8 of them and run them as pairs or 4's per channel, this will greatly improve the sound quality as the cone displacement will be halved ( two drivers) or quartered ( 4 drivers) per side.
I am traveling until next week so only on my phone but once I get back to base I can send you some info if you PM me with your email.
Hope this helps and all the best
Derek.