Philharmonic Audio BMR Philharmonitor Bookshelf Speaker Review

S

shadyJ

Speaker of the House
Staff member
You've lost me.

What happens to the bass when you cross to a sub? Is this thing that happens irrespective of crossover point?
Seems like he is saying that much of the virtues and benefits of a transmission line is lost when you use a high-pass filter on it, thereby handing much of its working frequency range over to a subwoofer.
 
Alex2507

Alex2507

Audioholic Slumlord
You've lost me.

What happens to the bass when you cross to a sub? Is this thing that happens irrespective of crossover point?
The bass is handled by the sub therefore the SongTower loses an opportunity to shine. The xo point determines how much the QWTL's LF prowess you are under utilizing. KEW is saying that when most of us go to a sub with the ST's because they are not quite full range, the speakers lose one of their strong suits.

Capice?
 
E

<eargiant

Senior Audioholic
Never, ever cross a fine speaker. Use a REL sub (via high level Neutrik) and run your speakers full range. You will be amazed. I just converted another skeptic this week. He only tried it because I hadn't steered him wrong in the past. He couldn't believe the difference.
 
S

shadyJ

Speaker of the House
Staff member
Never, ever cross a fine speaker. Use a REL sub (via high level Neutrik) and run your speakers full range. You will be amazed. I just converted another skeptic this week. He only tried it because I hadn't steered him wrong in the past. He couldn't believe the difference.
I'm not so sure that completely omitting bass management is normally a good idea.
 
Irvrobinson

Irvrobinson

Audioholic Spartan
I'm not so sure that completely omitting bass management is normally a good idea.
I agree. I use the run-the-mains-full-range strategy with two systems, and I found it'll work under two circumstances:

1. The mains have a relatively high F3 frequency, and you carefully adjust the low-pass filter of the sub to mesh with the roll-off of the mains. I use this strategy with my Audioengines 5+/SVS SB1000 combo, and it works "good enough". Not great, because the slopes of the responses aren't a great match, but good enough for video use and background music.

2. You manually implement sophisticated bass management via measurement and multiple PEQ settings on the sub(s) to fill in the dips and suck-outs of full-range mains. I do this with my Salon2/DD18 Plus system, and it is a lot of work to get it to be seamless and good enough for critical music listening. Sub placement and listening seat positioning are also important variables, so getting this right isn't for the lazy or impatient.

Just running mains that are capable down into the 32Hz and below full-range with a sub adjusted only by the low-pass frequency and perhaps phase always seems to result in a bloated 40-80Hz octave. Rock and roll fanatics may like it for the effect on some poorly-made recordings, but IMO it doesn't sound at all realistic.
 
JerryLove

JerryLove

Audioholic Samurai
The bass is handled by the sub therefore the SongTower loses an opportunity to shine. The xo point determines how much the QWTL's LF prowess you are under utilizing. KEW is saying that when most of us go to a sub with the ST's because they are not quite full range, the speakers lose one of their strong suits.
That sounds like a complaint of crossing over higher then the LF rolloff, and could be said of any speaker.

On a speaker flat to 40, crossing to a sub at 80 means you won't get the benefits of whatever that speaker is doing at 60; as you'll be using the sub instead.
 
KEW

KEW

Audioholic Overlord
That sounds like a complaint of crossing over higher then the LF rolloff, and could be said of any speaker.

On a speaker flat to 40, crossing to a sub at 80 means you won't get the benefits of whatever that speaker is doing at 60; as you'll be using the sub instead.
It sounds like you have a "unconventional" approach to crossing your sub(s).
I know you have a nice system. Would you remind us what it is and expain your approach to crossing the sub to the mains?

The "conventional" approach I am referring to is to cross to the sub in an area where both the sub and the mains have a reasonably linear response. Assuming you are using a typical AVR or Pre-pro, you want the AVR to manage the crossover without the natural roll-off of speakers or subs interfering with the hand off between them. An AVR/pre-pro crossover is designed to perform as indicated in the graph below and if you cross where a speaker rolls off, it will roll off too fast and result in a dip in the FR instead of the optimal FR as represented by the red line.

Somehow, I think you know all of this, so don't understand where you are coming from!!!

 
D

D Murphy

Full Audioholic
Just rereading last chain of posts: unless told otherwise, I would expect Salk's BMR cabinets to include the offset drivers... that's what his website shows, and if you review all his designs, you can see that is favored over a center alignment. :)
I'm afraid I'll have to tell you otherwise. The final version of the BMR has in-line drivers, and that's how Jim Salk will build them. The picture on his site is an older model. There are theoretical advantages to offsetting the mid and tweet, but I got push back on the looks and I wanted to simplify construction when I arranged for the Chinese cabinets. As it turned out, the in-line version had slightly smoother response and a little more focused sound. Very few manufacturers offset drivers, and you'll notice that Jim's more recent designs, including the flagship
SS 9.5, have all the drivers in line.
 
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KEW

KEW

Audioholic Overlord
I'm afraid I'll have to tell you otherwise. The final version of the BMR has in-line drivers, and that's how Jim Salk will build them. The picture on his site is an older model. There are theoretical advantages to offsetting the mid and tweet, but I got push back on the looks and I wanted to simplify construction when I arranged for the Chinese cabinets. As it turned out, the in-line version had slightly smoother response and a little more focused sound. Very few manufacturers offset drivers, and you'll notice that Jim's more recent designs, including the flagship
SS 9.5, have all the drivers in line.
Nice to see you back in circulation!
Take care!
 
ryanosaur

ryanosaur

Audioholic Overlord
I'm afraid I'll have to tell you otherwise. The final version of the BMR has in-line drivers, and that's how Jim Salk will build them. The picture on his site is an older model. There are theoretical advantages to offsetting the mid and tweet, but I got push back on the looks and I wanted to simplify construction when I arranged for the Chinese cabinets. As it turned out, the in-line version had slightly smoother response and a little more focused sound. Very few manufacturers offset drivers, and you'll notice that Jim's more recent designs, including the flagship
SS 9.5, have all the drivers in line.
Woohoo! Hi Dennis!
Thanks for the info!
 
JerryLove

JerryLove

Audioholic Samurai
It sounds like you have a "unconventional" approach to crossing your sub(s).
I know you have a nice system. Would you remind us what it is and expain your approach to crossing the sub to the mains?
I tend to cross at 80 as a reference and then experiment to see where I most like the sound. Most of what I use these days crosses at 80; but there have been some more "full range speakers" I've used as mains where I pushed the crossover down.

Somehow, I think you know all of this, so don't understand where you are coming from!!!
Some confusion on my side [and some poorly chosen numbers]
The statement was put out that "The bass is handled by the sub therefore the SongTower loses an opportunity to shine", and I don't understand how this is an issue related to anything other than crossover point (unless the speaker in question can go as low as the sub, which these cannot).

If speaker X can go lower than speaker Y, and you want to use that, then crossover speaker X lower than speaker Y and it will use more of its LF capability. Am I missing something in here?

I agree that it's probably in issue with one of us understanding the other (or both); I'm just not sure where that disconnect is located.
 
KEW

KEW

Audioholic Overlord
I tend to cross at 80 as a reference and then experiment to see where I most like the sound. Most of what I use these days crosses at 80; but there have been some more "full range speakers" I've used as mains where I pushed the crossover down.


Some confusion on my side [and some poorly chosen numbers]
The statement was put out that "The bass is handled by the sub therefore the SongTower loses an opportunity to shine", and I don't understand how this is an issue related to anything other than crossover point (unless the speaker in question can go as low as the sub, which these cannot).

If speaker X can go lower than speaker Y, and you want to use that, then crossover speaker X lower than speaker Y and it will use more of its LF capability. Am I missing something in here?

I agree that it's probably in issue with one of us understanding the other (or both); I'm just not sure where that disconnect is located.
It may be overly conservative, but I generally think in terms of wanting a full octave of neutral response beyond the crossover point. So for the Songtower with a bottom end of 38Hz (call it 40), I would be looking at 80 Hz for a minimum XO value.
This is the reason I would not use to much of the speaker's LF capability if I was using a subwoofer!
 
L

lewdogg

Enthusiast
Gonna wrap this up this coming Sunday (5/12). Wanted to post it one more time just in case some others wanted to donate to help Dennis. Many of you mentioned he probably doesn't NEED BMRs and that Jim would probably give Dennis a discount if he wanted to buy them. I plan to just provide the funds to Dennis and let him use it as he sees fit. I'm sure such a long stay in the hospital comes with a hefty bill so I wanted this campaign to provide some relief if needed.

https://www.gofundme.com/f/med-expensesfirst-salk-phil-bmr-for-dennis-murphy

Thanks again to everyone that donated!
 
L

lewdogg

Enthusiast
Updating everyone on the GFM campaign. Thanks to all the thoughtful members of the audio community, we raised $1,360 for Dennis, almost doubling the amount raised a week ago. The money should go to good use towards Dennis' medical expenses.

I want to thank everyone for all their donations and support!

Kevin
 
D

D Murphy

Full Audioholic
Updating everyone on the GFM campaign. Thanks to all the thoughtful members of the audio community, we raised $1,360 for Dennis, almost doubling the amount raised a week ago. The money should go to good use towards Dennis' medical expenses.

I want to thank everyone for all their donations and support!

Kevin
And I of course want to join in thanking all of you, and extra thanks to Kevin for starting this campaign. It's very gratifying to see this kind of support. It reminds you of what really matters. Cheers, Dennis
 
Swerd

Swerd

Audioholic Warlord
A kit to build the Philharmonic Audio BMR speaker has finally appeared at Meniscus Audio.
https://meniscusaudio.com/product/phiharmonic-audio-bmr-speaker-kit/

I understand that cabinets and/or routed front baffles should become available from a different source in the near future.

The basic Bare Bones kit from Meniscus Audio includes:
  • 2 × RAAL, 64-10 Ribbon Tweeter – We may have delays in getting the tweeters.
  • 2 × BMR 2.5″ mid-range
  • 2 × Scan-Speak, 18W8545-1 Paper-carbon cone woofer
  • 2 × Specified inductors
  • 2 × Choice of Capacitors
  • 2 × Lynk Resistors
  • Directions and build plans
The optional Full Kit add-on parts include:
  • 2 × Choice of terminals
  • 2 × 16ga Internal Hook up wire
  • 2 × Crossover mounting board and solder lugs
  • 2 × All mounting hardware
  • 2 × Internal damping materials
  • 2 × Precision Ports
Extra optional items include:
  • Assembled crossovers
 
slipperybidness

slipperybidness

Audioholic Warlord
A kit to build the Philharmonic Audio BMR speaker has finally appeared at Meniscus Audio.
https://meniscusaudio.com/product/phiharmonic-audio-bmr-speaker-kit/

I understand that cabinets and/or routed front baffles should become available from a different source in the near future.

The basic Bare Bones kit from Meniscus Audio includes:
  • 2 × RAAL, 64-10 Ribbon Tweeter – We may have delays in getting the tweeters.
  • 2 × BMR 2.5″ mid-range
  • 2 × Scan-Speak, 18W8545-1 Paper-carbon cone woofer
  • 2 × Specified inductors
  • 2 × Choice of Capacitors
  • 2 × Lynk Resistors
  • Directions and build plans
The optional Full Kit add-on parts include:
  • 2 × Choice of terminals
  • 2 × 16ga Internal Hook up wire
  • 2 × Crossover mounting board and solder lugs
  • 2 × All mounting hardware
  • 2 × Internal damping materials
  • 2 × Precision Ports
Extra optional items include:
  • Assembled crossovers
That puts it at a price point to compete with the Jeff Bagby Solstice! And, a fine price point for the BMR!
 
Verdinut

Verdinut

Audioholic Spartan
That puts it at a price point to compete with the Jeff Bagby Solstice! And, a fine price point for the BMR!
The only components which are questionable are the iron core inductors. For an overall slightly higher cost of the project, air core inductors are by far superior because they don't saturate and provide a more linear crossover transition. I guess that a prospective buyer could have them substituted by Meniscus.

Several years ago at Solen, I saw a reliable demonstration with proper testing equipment, by the late Denis Ouellet then president of the firm, of the undeniable superiority of an air core inductor.
 
D

D Murphy

Full Audioholic
The only components which are questionable are the iron core inductors. For an overall slightly higher cost of the project, air core inductors are by far superior because they don't saturate and provide a more linear crossover transition. I guess that a prospective buyer could have them substituted by Meniscus.

Several years ago at Solen, I saw a reliable demonstration with proper testing equipment, by the late Denis Ouellet then president of the firm, of the undeniable superiority of an air core inductor.
Was that comparison between an air core and a steel laminate? or just with a standard iron core? The engineers I know (including two well known crossover experts) swear by steel laminate core inductors for the woofer circuit. Not only are they cheaper (though not really inexpensive), they have lower dcr and perfectly satisfactory saturation points. I explicitly specified the steel laminates, and I used them in all of my BMR's.
 
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