Philharmonic Audio BMR Speaker Kit

Product Description

The Philharmonic Audio,  BMR Philharmonitor by Dennis Murphy

If you have been looking for a loudspeaker that plays orchestral music very well, you might look to a designer who plays violin in the Washington DC Philharmonic Orchestra. While complete systems from Dennis are on hiatus, you can build your own copy of this incredible monitor right now.

This is the newest member of the Philharmonic family. Dennis has developed this new 3-way design using the same RAAL ribbon tweeter. found in the New Philharmonitor. The mid-range is an innovative Balanced Mode Radiator (BMR). The woofer chosen is the 7″,  Scan-Speak 18W/8545.

The bass response extends to 34 Hz in a bass-reflex cabinet thanks to the optimization done by Paul Kittinger – an expert in mass-loaded transmission line design.  The BMR midrange and RAAL tweeter provide exceptional lateral dispersion and an expansive sound stage.  The 17-element crossover uses the same high-quality parts found in our more expensive speakers and blends the three drivers seamlessly.

The most unique feature of the new design is the Balanced Mode Radiator, a midrange driver.  Conventional drivers function in a simple piston-like fashion across their frequency range.  Eventually, the response becomes chaotic as severe breakup modes develop from the applied mass of the voice coil interacting with the driver mass, which greatly restricts the usable range of operation.  The BMR is a flat-diaphragm speaker that uses strategically placed weights in the diaphragm to counteract the mass of the voice coil at higher frequencies.

The BMR driver operates as a piston at lower frequencies, but shifts to a bending wave motion mode in the lower treble, and to a second bending mode in the upper treble.  The result is greatly reduced breakup and extremely broad dispersion above 2,000 Hz.  This driver is used as both a midrange and tweeter in several commercial applications.  Although the BMR can function acceptably in this fashion, its true strength is upper midrange performance.  The highest frequencies are much better served by the RAAL ribbon tweeter.

Bass frequencies are handled by a recently improved version of the classic Scan-Speak 8545 7-inch woofer.  This driver has long been noted for its superior bass reach and low harmonic distortion.  The large volume of the BMR cabinet and expert port tuning by Paul Kittinger allow the Scan-Speak woofer to provide a useful bass response to 34 Hz.  This means you can experience the power of a pipe organ or bass drum without the expense of a tower speaker or the complexity of a subwoofer.

“These speakers are awesome. The tonality revealed things in songs I’d never heard before (in only one case did I find that to be a negative). The resolution reveals little details such as slight inflections in voices and even accentuates the breathing-in of a vocalist before they begin their next line. It was a new experience for me to hear these kinds of details. The soundstage is incredibly large and well balanced and the reflections in the room help to extend the soundstage to a size I’ve yet to hear from another speaker to date.”

See the reviews here:

Audioholics Review

“Erins Audio” review

• Freq. Response – 34Hz- 20 Khz
• Sensitivity 85dB  (dB/2.83v/1M)
• Dimensions  20″ H x 8″ W x 12-1/2″ D
• Impedance 6 ohm

• 2 x RAAL, 64-10 Ribbon Tweeter – We may have delays in getting the tweeters.
• 2 x BMR 2.5″ mid-range
• 2 x Scan-Speak, 18W8545-1 Paper-carbon cone woofer
• 2 x Inductors specified by Dennis
• 2 x Audy Q4 on tweeter and Solen Fast Caps throughout,  (Audyn pictured) – or choose to your favorite brand
• 2 x Sand-cast  Resistors – or choose your favorite brand
• Directions and build plans

The optional Full Kit add-on parts include:

• 2 x Add Choice of terminals (not included in base price)
• 2 x 16ga  Internal Hook up wire
• 2 x Crossover mounting board and solder lugs
• 2 x All mounting hardware
• 2 x Internal damping materials
• 2 x Precision Ports

Extra optional items include:

• Assembled crossovers Option

We are happy to customize this kit for you – different capacitors, etc. – even if we don’t normally stock them. Just let us know your preferences and we can quote accordingly.  Some component upgrades are listed above in the drop-down when ordering.