Silk surround BMR
Hi All,
I finally got to hear Derek's (Overkill Audio) new BMR driver with the silk surround today & what a beautiful piece of kit it is, for midrange & up it just floods clean,crisp,dynamic,effortless sound into the room, even at very high spl's & with only one BMR in each monitor.
I was already sold on these drivers for midrange up having run my own pair for over a year now but these new generation drivers really do take the performance up a significant step.
Unfortunately (but understandably) Derek is keeping these drivers for his studio monitors & not for sale to DIY users, even so, it is a taste of technology to come & surely at last marks the beginning of the end for the mid/tweeter combo ?
A big thank you to Derek for letting me spend hours today listening to them !
Hi All,
I finally got to hear Derek's (Overkill Audio) new BMR driver with the silk surround today & what a beautiful piece of kit it is, for midrange & up it just floods clean,crisp,dynamic,effortless sound into the room, even at very high spl's & with only one BMR in each monitor.
I was already sold on these drivers for midrange up having run my own pair for over a year now but these new generation drivers really do take the performance up a significant step.
Unfortunately (but understandably) Derek is keeping these drivers for his studio monitors & not for sale to DIY users, even so, it is a taste of technology to come & surely at last marks the beginning of the end for the mid/tweeter combo ?
A big thank you to Derek for letting me spend hours today listening to them !
I previously heard the 16 driver line arrays with two subs, one 12" & one 15", the silk BMR's I heard today were single drivers in studio monitors with 15" midbass drivers.
I couldn't help dreaming about a mini inwall array of four silk BMR's underpinned with a nice pair of bass/sub cabinets
New kid on the block
Hiya Jason,
Good to see you again today and glad you like my new studio monitors, they really do something special.
Once I get our electronics sorted out I might even be tempted to do a show and get a few reviews!
Studio Au,
I have attached a pic of the speakers Jason heard today, the system was:
A pair of 10 year old Overkill (Belles with upgraded power supplies and Bybee's) amps.
DEQX in digital out mode.
Our new 4 channel CIA DAC (using AKM 4495 chips)
Source was a lap top with SSD and JRiver via a 5 meter long, basic USB cable.
All the best
Derek.
Hiya Jason,
Good to see you again today and glad you like my new studio monitors, they really do something special.
Once I get our electronics sorted out I might even be tempted to do a show and get a few reviews!
Studio Au,
I have attached a pic of the speakers Jason heard today, the system was:
A pair of 10 year old Overkill (Belles with upgraded power supplies and Bybee's) amps.
DEQX in digital out mode.
Our new 4 channel CIA DAC (using AKM 4495 chips)
Source was a lap top with SSD and JRiver via a 5 meter long, basic USB cable.
All the best
Derek.
Attachments
RED is in, BMR is out.... Kits will now be available!
Hi Guys,
We have been working hard on the driver (& DSP) R&D front and the news is goodbye BMR....Hello Rapid Energy Decay (RED).....Might need to start a new thread?
The bottom line is the latest series of changes to our flat coned silk surround & linen / silk spider plus new voice coil has altered the fundamentals of the driver so much that technically it no longer operates as a true BMR.
We have focused all our efforts on two aspects:
(1) The energy storage / decay performance
(2) Power response (broadest possible on and off axis frequency response)
The latest results are very encouraging......This compact near-field monitor is a real sweetie!
Another benefit of having our own driver IP is that it is now free from any BMR licencing issues & fees and this allows us to make some DIY kits available.....Yea!
The cabinet is 25cm by 40cm by 20cm (WHD) in 18mm birch ply and will come with all the fixtures and fittings required to build a pair of very high performance monitors.
The design requires a DSP crossover / Eq and we can bundle the kits with several options, more details on request, PM please.
In under 10 litres sealed air volume our 8 inch paper and carbon fiber coned bass mid is flat to 48Hz with good output down to 38Hz.
Mms to Bl ratio of 1.5 is a great match with our 1.25 silk surround RED driver and crossover can be anywhere from 200Hz to 400Hz depending on SPL requirements.
Limited availability at the moment, but should be ready to ship by May.
Hope this helps and all the best
Derek.
Hi Guys,
We have been working hard on the driver (& DSP) R&D front and the news is goodbye BMR....Hello Rapid Energy Decay (RED).....Might need to start a new thread?
The bottom line is the latest series of changes to our flat coned silk surround & linen / silk spider plus new voice coil has altered the fundamentals of the driver so much that technically it no longer operates as a true BMR.
We have focused all our efforts on two aspects:
(1) The energy storage / decay performance
(2) Power response (broadest possible on and off axis frequency response)
The latest results are very encouraging......This compact near-field monitor is a real sweetie!
Another benefit of having our own driver IP is that it is now free from any BMR licencing issues & fees and this allows us to make some DIY kits available.....Yea!
The cabinet is 25cm by 40cm by 20cm (WHD) in 18mm birch ply and will come with all the fixtures and fittings required to build a pair of very high performance monitors.
The design requires a DSP crossover / Eq and we can bundle the kits with several options, more details on request, PM please.
In under 10 litres sealed air volume our 8 inch paper and carbon fiber coned bass mid is flat to 48Hz with good output down to 38Hz.
Mms to Bl ratio of 1.5 is a great match with our 1.25 silk surround RED driver and crossover can be anywhere from 200Hz to 400Hz depending on SPL requirements.
Limited availability at the moment, but should be ready to ship by May.
Hope this helps and all the best
Derek.
Hi Alvipet,
Both drivers are 4 Ohm and this gives 91dB (plus / minus 0.7 dB) for 2.83 volts at 1 meter.
The drivers can be measured individually or with the DSP crossover in place and the results remain almost identical....They really blend superbly.
We cross over the RED driver well above well its box resonance & the impedance curve is almost totally flat.
Our bass / mid drivers suspension / Fs is tuned to give a box resonance of 154 Hz / Q 0.707 in just over 6 litres of air, this reduces the energy at box resonance by over 80% compared to a conventional 35Hz to 40Hz Fb using a low Fs driver.
Its interesting to look at the energy spread:
For every octave lower you have to deal with 4 times the energy (4 times the driver travel with the same mass) so by placing the Fb as high as possible you minimise the energy you are dealing with at Fb and benefit from a perfectly flat low midrange and bass impedance.
Hope this helps and all the best
Derek.
Both drivers are 4 Ohm and this gives 91dB (plus / minus 0.7 dB) for 2.83 volts at 1 meter.
The drivers can be measured individually or with the DSP crossover in place and the results remain almost identical....They really blend superbly.
We cross over the RED driver well above well its box resonance & the impedance curve is almost totally flat.
Our bass / mid drivers suspension / Fs is tuned to give a box resonance of 154 Hz / Q 0.707 in just over 6 litres of air, this reduces the energy at box resonance by over 80% compared to a conventional 35Hz to 40Hz Fb using a low Fs driver.
Its interesting to look at the energy spread:
For every octave lower you have to deal with 4 times the energy (4 times the driver travel with the same mass) so by placing the Fb as high as possible you minimise the energy you are dealing with at Fb and benefit from a perfectly flat low midrange and bass impedance.
Hope this helps and all the best
Derek.
Single drivers are 91dB....Arrays are up to 100dB sensitivity
Hi methodarn,
Depending on what amps / room size / SPL's we can tailor kits to suit most needs, from valve and vinyl systems to solid state / DSP.
For valve amp users we have a very nice 8 Ohm flat resistive load with 97dB for 2.83 volts at 1 meter. Its an 8 driver array (4 groups of 2 Ohms wired in series) which is 940mm tall. Width and depth is 150mm by 250mm but can be altered to suit floor standing or wall mounted.
This design can be crossed over as low as 80 Hz, but peak performance is reached with a 300Hz crossover.
It could be run full range with no crossover but it needs Eq which can be done at source if you use JRiver or similar as a source. This would limit max SPL's but it will still be more than enough for most rooms.
Hope this helps and all the best
Derek.
Hi methodarn,
Depending on what amps / room size / SPL's we can tailor kits to suit most needs, from valve and vinyl systems to solid state / DSP.
For valve amp users we have a very nice 8 Ohm flat resistive load with 97dB for 2.83 volts at 1 meter. Its an 8 driver array (4 groups of 2 Ohms wired in series) which is 940mm tall. Width and depth is 150mm by 250mm but can be altered to suit floor standing or wall mounted.
This design can be crossed over as low as 80 Hz, but peak performance is reached with a 300Hz crossover.
It could be run full range with no crossover but it needs Eq which can be done at source if you use JRiver or similar as a source. This would limit max SPL's but it will still be more than enough for most rooms.
Hope this helps and all the best
Derek.
Hi guys !What this new phenomenon ... Is it new It's a fundamentally new technology or variation of BMR ?
Evolution not revolution...
Hi Nickolay,
The new RED driver has evolved over many years, going back 15 years or with the Manger Bending Mode driver, a decade with cones / domes / ribbons and AMT's, through the last 5 years with a whole series of BMR's....
The RED driver is a culmination of everything I have learned combined with the results of our JV with Manchester University, the teams computer aided design and cutting edge materials science has taken the project to a new level.
We are currently writing some more patent applications and working on the best DFT & DFM (Design For Test and Design For Manufacture) techniques.
Looking forward to 2016 and being able to supply some kits into the DIY and custom install markets!
Hope this helps and all the best
Derek.
Hi Nickolay,
The new RED driver has evolved over many years, going back 15 years or with the Manger Bending Mode driver, a decade with cones / domes / ribbons and AMT's, through the last 5 years with a whole series of BMR's....
The RED driver is a culmination of everything I have learned combined with the results of our JV with Manchester University, the teams computer aided design and cutting edge materials science has taken the project to a new level.
We are currently writing some more patent applications and working on the best DFT & DFM (Design For Test and Design For Manufacture) techniques.
Looking forward to 2016 and being able to supply some kits into the DIY and custom install markets!
Hope this helps and all the best
Derek.
This new RED driver sounds really really interesting. Will the driver be available on it's own? or only as part of a kit? In your 10 litre example does the RED share the cabinet or is it sealed apart front the woofer? Maybe I'm getting the cart before the horse but it does seem to open up new possibilities in the FAST design area. What is the RED drivers upper frequency limit?
Hi Derek,
Any updates? I read the whole thread and after all the excitement the twist came in the last few posts
I must admit I am really confused at the moment. Could you start a new thread or at least put the whole concept into few sentences, please?
I saw this product as something that would complement my system which would consist of GR Research OB woofers for 200Hz and down, and this on top of it.
I am into OB bass as it handles lots of room modes and it doesn't require so much room treatment.
...anyhow, a very interesting read so far.
Thanks a lot!!!
RED driver update
Hi mirekti,
For sure I will start a new thread in the commercial vendors section when I have stock ready to ship, I am hoping to be ready by June, it all depends on the DSP which is taking longer than expected.
I have a few beta test drivers that I would like to see used in high performance DIY set ups, preferably in the UK so I can assist with the installation. PM me if your interested.
Re the tech points you mention:
I always use separate sealed chambers for each driver, even in line arrays and I never mix n match bass with RED driver air volumes.
The RED driver is designed to cover 200Hz to 20KHz and be used with a DSP for Eq and crossover, our own DSP will be the best option but any DSP can be used.
Used in a small (Vb 3 litre) sealed cabinet the RED driver is an ideal match with open baffle / bass low midrange as both systems major on fast low distortion performance.
My long term reference for open baffle is the Manger driver (see attached pic) crossing over at 500Hz to twin 15 inch open baffle bass / low mid drivers (Precision Devices and Beyma) and the results are really superb.
The RED drivers are a clear improvement over the Manger driver and give a significant increase in performance.
I am currently testing some line arrays (9 RED driver per side) in a home cinema set up using a Yamaha AV amp for crossover and DSP.
Crossing over at at 200Hz (the max on the AV amp) to 15 inch bass / low midrange drivers in 50 litre sealed box and they are remarkable....The ability to separate out tiny details from soundtracks and reveal sonic details to match the on screen visual effects is astounding.
For studio monitors we use the RED driver with DSP linear phase crossovers and Eq, 48dB per octave at 300Hz allows the driver to hit very high SPL's and maintain a clear and natural sound Eq'd flat to 20KHz.
Thats about it at the moment, I will post a few pics of some DIY cabinet kits using CNC'd laminated Baltic birch plywood, they are very cool!
Hope this helps and all the best
Derek.
Hi mirekti,
For sure I will start a new thread in the commercial vendors section when I have stock ready to ship, I am hoping to be ready by June, it all depends on the DSP which is taking longer than expected.
I have a few beta test drivers that I would like to see used in high performance DIY set ups, preferably in the UK so I can assist with the installation. PM me if your interested.
Re the tech points you mention:
I always use separate sealed chambers for each driver, even in line arrays and I never mix n match bass with RED driver air volumes.
The RED driver is designed to cover 200Hz to 20KHz and be used with a DSP for Eq and crossover, our own DSP will be the best option but any DSP can be used.
Used in a small (Vb 3 litre) sealed cabinet the RED driver is an ideal match with open baffle / bass low midrange as both systems major on fast low distortion performance.
My long term reference for open baffle is the Manger driver (see attached pic) crossing over at 500Hz to twin 15 inch open baffle bass / low mid drivers (Precision Devices and Beyma) and the results are really superb.
The RED drivers are a clear improvement over the Manger driver and give a significant increase in performance.
I am currently testing some line arrays (9 RED driver per side) in a home cinema set up using a Yamaha AV amp for crossover and DSP.
Crossing over at at 200Hz (the max on the AV amp) to 15 inch bass / low midrange drivers in 50 litre sealed box and they are remarkable....The ability to separate out tiny details from soundtracks and reveal sonic details to match the on screen visual effects is astounding.
For studio monitors we use the RED driver with DSP linear phase crossovers and Eq, 48dB per octave at 300Hz allows the driver to hit very high SPL's and maintain a clear and natural sound Eq'd flat to 20KHz.
Thats about it at the moment, I will post a few pics of some DIY cabinet kits using CNC'd laminated Baltic birch plywood, they are very cool!
Hope this helps and all the best
Derek.
Dedicated webpage will follow
Yes we will create a DIY section on our www.custominstallaudio.com website
At the moment our website is out of date as we have not finished all the DSP and RED driver work, once that is signed off we are going to completely re design the website.
All the commercial install and DIY kits will be in one section with the studio monitors / cinema monitors and Pro Sound gear on another section.
We might even do a high end audio design or two, no money in that market but its good fun kicking the a** off the big brand names at the shows....!!
Yes we will create a DIY section on our www.custominstallaudio.com website
At the moment our website is out of date as we have not finished all the DSP and RED driver work, once that is signed off we are going to completely re design the website.
All the commercial install and DIY kits will be in one section with the studio monitors / cinema monitors and Pro Sound gear on another section.
We might even do a high end audio design or two, no money in that market but its good fun kicking the a** off the big brand names at the shows....!!
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I can see there is already a patent for the speaker I plan on building. Patent WO2000067524A2 - Bending wave loudspeakers - Google Patents
I wonder why there were no commercial versions of it.
Anyhow, looking forward to seeing your work and these new RED drivers.
One more technical question. Could you put a few words about what a net effect or lost happens when the line array is not 75% or more of the ceiling height?
I wonder why there were no commercial versions of it.
Anyhow, looking forward to seeing your work and these new RED drivers.
One more technical question. Could you put a few words about what a net effect or lost happens when the line array is not 75% or more of the ceiling height?