Uncertainty

[D Murphy]

Dennis - Any chance of a Phil 3 kit ???

'fraid not. Too complicated and expensive.

 

[D Murphy]

What do you think the advantages of a narrow vertical dispersion would be? I would think that, so long as the response isn't badly non-linear, it should sound pretty natural, much like lateral reflections. Of course, the vertical reflections of many speakers are far from perfect. I do remember reading about some study that was done on the effects of ground bounce cancellation in bass, and in the end it wasn't very deleterious because like many acoustics issues, human hearing seemed to adjust for it very quickly. Floyd Toole discusses it in his book, although I don't have my copy handy so I can't site the specific paper at the moment.

First off, I'm totally agnostic on the benefits of limited vertical dispersion. I'm not expecting any improvement to come from reduced floor bounce. The method my friend is using to control dispersion (which is based on radar theory)can't do much with the longer bass waves. The effect will be most pronounced in the midrange and treble. Reflections off of the floor and ceiling will generally arrive before lateral reflections in most setups, and perhaps the thinking is that those early reflections may muddy up the direct sound. All I have to go on is my auditioning of the first speaker my friend built that incorporated his approach to limiting vertical dispersion, and I thought the sound was exceptionally clean and "see through," enough so that I had Jim Salk fly down to hear it. That prototype is too complicated to produce commercially, however, and it uses a very shallow cabinet that mounts flush up against the wall behind it. The speaker we're doing now uses a more conventional tower cabinet and the same mids that are in my BMR along with a RAAL tweeter and Scan woofers, , so I think we'll have a better test when we can switch back and forth between those speakers.

 

[shadyJ]

First off, I'm totally agnostic on the benefits of limited vertical dispersion. I'm not expecting any improvement to come from reduced floor bounce. The method my friend is using to control dispersion (which is based on radar theory)can't do much with the longer bass waves. The effect will be most pronounced in the midrange and treble. Reflections off of the floor and ceiling will generally arrive before lateral reflections in most setups, and perhaps the thinking is that those early reflections may muddy up the direct sound. All I have to go on is my auditioning of the first speaker my friend built that incorporated his approach to limiting vertical dispersion, and I thought the sound was exceptionally clean and "see through," enough so that I had Jim Salk fly down to hear it. That prototype is too complicated to produce commercially, however, and it uses a very shallow cabinet that mounts flush up against the wall behind it. The speaker we're doing now uses a more conventional tower cabinet and the same mids that are in my BMR along with a RAAL tweeter and Scan woofers, , so I think we'll have a better test when we can switch back and forth between those speakers.

I remember you mentioned that design, it was interesting. Another approach to eliminating vertical dispersion was Don Keele's CBT speakers which I thought were pretty neat. The width of dispersion patterns are one area that there doesn't seem to be any settled research regarding human preference. As you know, Sean Olive, Floyd Toole, et al. advocate for a wider dispersion for more early reflections, although that isn't what their research focused on. You seem to be sympathetic to this view and design your speakers accordingly. Whereas Earl Geddes and his diabolical henchman Matthew Poes are for a tighter dispersion pattern. There are those who argue for an extremely narrow dispersion pattern such as you get from flat panel speakers like Magnapan to remove the room as much as possible for head-in-a-vice listening. I have heard good sound from all kinds of dispersion patterns, even some good omnipolar speakers, so I am not too picky about that, but some real research into typical preferences would be interesting. My guess is we wouldn't see as overwhelming preference for one type of dispersion as is seen in preference for a neutral response among response shapes.

 

[Swerd]

@Jack N

I'm not Dennis, but I doubt if a Phil 3 flat-pack cabinet kit will be offered. The two cabinets are considerably more complex to build than the simpler BMR.

I've heard both, and I believe BMR speakers alone are highly satisfying. Combined with a suitable sub-woofer, they would leave little more to desire.

 

[shadyJ]

@Jack N

I'm not Dennis, but I doubt if a Phil 3 flat-pack cabinet kit will be offered. The two cabinets are considerably more complex to build than the simpler BMR.

I've heard both, and I believe BMR speakers alone are highly satisfying. Combined with a suitable sub-woofer, they would leave little more to desire.

If you aren't cranking the bass hard, you don't need a sub with the BMR Philharmonitors. Their bass extension is lower than many tower speakers I have used.

 

[Jack N]

If the BMR kit thing works out and hopefully an audition, I'm sure I'll go that way. Just like everybody else, clarity, neutral sound, and as much bass extension as I can get are what I'm looking for and it sounds like these excel at that. Looking forward to it.

Dennis - I sure hope you can offer them in piano gloss black. I'll keep my fingers crossed.

 

[Swerd]

If the BMR kit thing works out and hopefully an audition, I'm sure I'll go that way. Just like everybody else, clarity, neutral sound, and as much bass extension as I can get are what I'm looking for and it sounds like these excel at that. Looking forward to it.

Dennis - I sure hope you can offer them in piano gloss black. I'll keep my fingers crossed.

From what I understand of the flat-pack cabinet kits, they are pieces of Baltic birch plywood pre-cut to the proper dimensions. The front baffle has the necessary cutout holes for mounting the drivers, and the rear panel has a hole for the port tube. Gluing up the cabinet pieces, assembling the speaker components, and wood finishing is left to the owner.

Dennis, please correct me if I'm wrong.

If you're interested in a glossy paint finish, please understand that it's difficult to do this well. The wood surface has to be filled, sealed, and sanded until its quite smooth. Any grain or flaws will show through the painted finish, especially with a glossy finish. The process requires many layers of paint and clear coat, with fine sanding in between coats. This requires relatively dust free spraying and drying rooms. I've tried a glossy paint finish once, and was not happy with the results. In my experience, veneer is actually easier to apply, and has better looking results.

A better way to get a glossy paint finish, is to take the assembled cabinets, minus the drivers and wiring, to a few auto paint shops and ask for their prices. They are properly equipped for filling, sanding, and spray paint finishing. They might laugh at first because they don't often see anything but cars, but you might be surprised at an affordable price. The results will probably be much better than anything most DIY people can do at home.

 

[D Murphy]

From what I understand of the flat-pack cabinet kits, they are pieces of Baltic birch plywood pre-cut to the proper dimensions. The front baffle has the necessary cutout holes for mounting the drivers, and the rear panel has a hole for the port tube. Gluing up the cabinet pieces, assembling the speaker components, and wood finishing is left to the owner.

Dennis, please correct me if I'm wrong.

If you're interested in a glossy paint finish, please understand that it's difficult to do this well. The wood surface has to be filled, sealed, and sanded until its quite smooth. Any grain or flaws will show through the painted finish, especially with a glossy finish. The process requires many layers of paint and clear coat, with fine sanding in between coats. This requires relatively dust free spraying and drying rooms. I've tried a glossy paint finish once, and was not happy with the results. In my experience, veneer is actually easier to apply, and has better looking results.

A better way to get a glossy paint finish, is to take the assembled cabinets, minus the drivers and wiring, to a few auto paint shops and ask for their prices. They are properly equipped for filling, sanding, and spray paint finishing. They might laugh at first because they don't often see anything but cars, but you might be surprised at an affordable price. The results will probably be much better than anything most DIY people can do at home.

Wise words. If the cabinet shop does offer a piano black or white finish, it would be done with auto paint. The owner mentioned that possibility, but we haven't discussed it further. I think he's on vacation until the new year, but I'll talk to him about that when he gets back.

 

[everettT]

From what I understand of the flat-pack cabinet kits, they are pieces of Baltic birch plywood pre-cut to the proper dimensions. The front baffle has the necessary cutout holes for mounting the drivers, and the rear panel has a hole for the port tube. Gluing up the cabinet pieces, assembling the speaker components, and wood finishing is left to the owner.

Dennis, please correct me if I'm wrong.

If you're interested in a glossy paint finish, please understand that it's difficult to do this well. The wood surface has to be filled, sealed, and sanded until its quite smooth. Any grain or flaws will show through the painted finish, especially with a glossy finish. The process requires many layers of paint and clear coat, with fine sanding in between coats. This requires relatively dust free spraying and drying rooms. I've tried a glossy paint finish once, and was not happy with the results. In my experience, veneer is actually easier to apply, and has better looking results.

A better way to get a glossy paint finish, is to take the assembled cabinets, minus the drivers and wiring, to a few auto paint shops and ask for their prices. They are properly equipped for filling, sanding, and spray paint finishing. They might laugh at first because they don't often see anything but cars, but you might be surprised at an affordable price. The results will probably be much better than anything most DIY people can do at home.

I attempted once years ago to do a high gloss finish in the garage and let's just say it didn't go very smoothly. You really need the right environment 1, 2nd the right HPLV gun and 3. lots of patience. I stopped after the 4th coat...

 

[Jack N]

I was born totally devoid of wood finishing skills. Several years ago I tried staining a new door. I figured “How hard can this be?” It turned out so ugly I ended up taking it to the local cabinet maker to get it fixed.

I like the body shop idea.