Hi everyone. I'm finally joining this community which I've learnt a lot from, but I've a few questions that I'm itching to find good answers.
The topic? Powered BMR monitor speakers with a three-way active crossover.
Tweeter: Raal 64-10 (crossed LR4 3400Hz)
Midrange: Tectonic TEBM46C20N-4B BMR 3" (crossed LR4 400Hz)
Woofer: Dayton Epique 180HE-44 7" in a passive radiator sealed box.
Background: I'm really a big fan of Mr. Dennis Murphy's work and wanted to emulate the philharmonic BMR monitors. The extremely wide horizontal dispersion granted by the BMR midrange and raal ribbon is something very appealing and different from any other three way speaker design and made me want to emulate his design. On the way, why not make it an active speaker? Getting past complex passive crossovers means that the amp will see a simple load&reduce back-emf, lower IMD, reduce power loss, and I don't need to deal with crossover complexities. The Xkits active crossover modules are LR4, and the flat performance of the BMR and 64-10 are perfect together.
As for choice of woofer, why these? Why not? Given enough power, these produce decent bass for a 7inch woofer, and measure decently while being compact. And PRs simplify things a lot. For amplification, I'm using two class AB amps for the midrange and tweeter, and class D for bass, but discussion about these will be limited here to focus on the questions.
So my questions are:
1) Given that a rounded side baffle can improve horizontal radiation, is there such a thing as too much rounding? As I know, a more sudden curve can affect longer frequencies more than shorter ones, and so negatively impact horizontal radiation. If this is the case, a more flat baffle might be appropriate.
- There is a simulation for rounded baffles giving very smooth horizontal radiation.
https://www.audiosciencereview.com/.../philharmonic-bmr-speaker-review.14781/page-5
2) Should I stay with the three way WMT design or go for WMTM?
- As much as I love Mr Dennis's BMR monitor design, I'm really tempted to try out his BMR tower design with WMTM using the same BMR and ribbon
- https://philharmonicaudio.com/products/bmr-tower
- Why MTM?
- a single 3" midrange may benefit from an extra one to allow higher SPL capability, lower distortion, and more controlled (albeit narrower) vertical dispersion
- use of a ribbon means a narrow vertical dispersion anyway
- but there's reason for not needing an extra bmr: https://www.erinsaudiocorner.com/loudspeakers/philharmonic_bmr_v2/
- a single BMR exhibits low HD and performs well in the compression test
- A WMTM will look glorious (99% this is the reason). Really, why not? Just go for it?
Thank you, and appreciate any input regarding this.
The topic? Powered BMR monitor speakers with a three-way active crossover.
Tweeter: Raal 64-10 (crossed LR4 3400Hz)
Midrange: Tectonic TEBM46C20N-4B BMR 3" (crossed LR4 400Hz)
Woofer: Dayton Epique 180HE-44 7" in a passive radiator sealed box.
Background: I'm really a big fan of Mr. Dennis Murphy's work and wanted to emulate the philharmonic BMR monitors. The extremely wide horizontal dispersion granted by the BMR midrange and raal ribbon is something very appealing and different from any other three way speaker design and made me want to emulate his design. On the way, why not make it an active speaker? Getting past complex passive crossovers means that the amp will see a simple load&reduce back-emf, lower IMD, reduce power loss, and I don't need to deal with crossover complexities. The Xkits active crossover modules are LR4, and the flat performance of the BMR and 64-10 are perfect together.
As for choice of woofer, why these? Why not? Given enough power, these produce decent bass for a 7inch woofer, and measure decently while being compact. And PRs simplify things a lot. For amplification, I'm using two class AB amps for the midrange and tweeter, and class D for bass, but discussion about these will be limited here to focus on the questions.
So my questions are:
1) Given that a rounded side baffle can improve horizontal radiation, is there such a thing as too much rounding? As I know, a more sudden curve can affect longer frequencies more than shorter ones, and so negatively impact horizontal radiation. If this is the case, a more flat baffle might be appropriate.
- There is a simulation for rounded baffles giving very smooth horizontal radiation.
https://www.audiosciencereview.com/.../philharmonic-bmr-speaker-review.14781/page-5
2) Should I stay with the three way WMT design or go for WMTM?
- As much as I love Mr Dennis's BMR monitor design, I'm really tempted to try out his BMR tower design with WMTM using the same BMR and ribbon
- https://philharmonicaudio.com/products/bmr-tower
- Why MTM?
- a single 3" midrange may benefit from an extra one to allow higher SPL capability, lower distortion, and more controlled (albeit narrower) vertical dispersion
- use of a ribbon means a narrow vertical dispersion anyway
- but there's reason for not needing an extra bmr: https://www.erinsaudiocorner.com/loudspeakers/philharmonic_bmr_v2/
- a single BMR exhibits low HD and performs well in the compression test
- A WMTM will look glorious (99% this is the reason). Really, why not? Just go for it?
Thank you, and appreciate any input regarding this.
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