[Mag]

Listening to my Model T passives, I'm totally impressed with the imaging, let me tell you about it.

In my 25'x 11'x 8' room I have the speakers placed along the long wall approx. 10' apart. I have them reflecting off the back wall about 2' to the left & right of my seating position.

The direct sound, sounds like it's coming off the front wall in an 10'x 8' soundstage. This is just a phantom image but it sounds like a full powered speaker. The speakers are merely the boundary of this soundstage in which the sound is not localized.

Very impressive imaging, of course YMMV depending on the room.

[James Tanner]

Listening to my Model T passives, I'm totally impressed with the imaging, let me tell you about it.

In my 25'x 11'x 8' room I have the speakers placed along the long wall approx. 10' apart. I have them reflecting off the back wall about 2' to the left & right of my seating position.

The direct sound, sounds like it's coming off the front wall in an 10'x 8' soundstage. This is just a phantom image but it sounds like a full powered speaker. The speakers are merely the boundary of this soundstage in which the sound is not localized.

Very impressive imaging, of course YMMV depending on the room.

Hi Mag

Thank you for this post because it points out one of the main benefits of the Bryston speakers - and that is what we call the 'Family of Curves'. 

Which is - the frequency response is even all around the speaker - we do hundreds of measurements in the anechoic chamber both - vertically and horizontally - and make them as flat as possible in every direction.  This is sometimes referred too as the SOUND POWER and that is really what you hear when you place a speaker in a room. 

The walls and ceiling and floor are all contributing to this 'sound power' and if all those reflections are similar in tonal balance to the on-axis response of the speaker you end up with this huge soundstage where the room disappears

james

[JfTM]

Hi Mag

Thank you for this post because it points out one of the main benefits of the Bryston speakers - and that is what we call the 'Family of Curves'. 

Which is - the frequency response is even all around the speaker - we do hundreds of measurements in the anechoic chamber both - vertically and horizontally - and make them as flat as possible in every direction.  This is sometimes referred too as the SOUND POWER and that is really what you hear when you place a speaker in a room. 

The walls and ceiling and floor are all contributing to this 'sound power' and if all those reflections are similar in tonal balance to the on-axis response of the speaker you end up with this huge soundstage where the room disappears

james

Isn't this what Roy Allison pioneered in the 70's?

Full disclosure, I still have a pair of Allison Three's and a bunch of Bryston equipment.

Oops, just realized, I'm not looking for an IP battle here.

[James Tanner]

Isn't this what Roy Allison pioneered in the 70's?

Full disclosure, I still have a pair of Allison Three's and a bunch of Bryston equipment.

Oops, just realized, I'm not looking for an IP battle here.

Hi

Not sure on that - do you have any old literature or white papers you could send me from Allison?

james

[Phil A]

James - did not read the whole thing but here is an interview with Roy - http://www.avhub.com.au/index.php/Features/Hi-Fi/roy-f-allison-interview.html

[Phil A]

A couple of more links I found

http://www.audiocircuit.com/Home-Audio/Allison-Acoustics

http://www.stereophile.com/content/glorious-time-ars-edgar-villchur-and-roy-allison-allison-part-2

[James Tanner]

Thanks for this

Comment By Roy

SM: What do you consider to be the most important design criteria for a loudspeaker?

RA: Flatness of power response over the widest possible frequency range, and uniform dispersion of that power into the solid angle of radiation. Low distortion at available radiated power. Efficiency adequate for the intended use. Convenience of placement in the domestic environment.

[veloceleste]

When I first started reading this part of the thread Allison immediately came to mind also. I've owned all the original series Allison speakers at one time or another and they remain one of my vintage favorites. Placement and the room boundary interface was critical to their sound. Now I may have to go listen to the Bryston speakers

[JfTM]

Thanks for this

Comment By Roy

SM: What do you consider to be the most important design criteria for a loudspeaker?

RA: Flatness of power response over the widest possible frequency range, and uniform dispersion of that power into the solid angle of radiation. Low distortion at available radiated power. Efficiency adequate for the intended use. Convenience of placement in the domestic environment.

And a key part of Roy's solution was to design unique high frequency drivers, that moved to point source.