[jsalk]

We just finished modeling two new BePure Center channel speakers.

The first is a smaller center using 4.5" BePure woofers.  These things are amazing.  I don't want to state the final F3 at this point, but I was shocked at how low these things will play according to the modeling.  What's nice about this design is that it can be used as a horizontal center channel as well as vertical monitors.  So it will be called the BePure 2 M/C (Monitor/Center).  It should result in a compact design that would work well for home theater and could be used for all front three speakers.

The second center channel will use a pair of 6.5" woofers with side-firing passive radiators.  So it will be larger and is designed to be free-standing (since the passives are mounted on the sides (ends) of the cabinet).  The only question remaining on this one is whether it should be a 2-way or a 3-way.  Based on the performance of the BePure 2's, a 2-way will perform quite well.  But since this is a higher end center channel, a 3-way version may be more appropriate, although more costly.  So the jury is still out on this one.  But we should make a final decision soon.

Either way, we'll have some great center channels in the BePure line.

I also looked at a small single 4.5" woofer design for surround speakers.  Unfortunately, the sensitivity turned out to be too low for me to feel comfortable offering.  It would work but would require quite a few watts to drive.  Of course, we have a number of other designs that would work well for surround duty in a BePure home theater set-up. 

As you can tell, I'm totally in awe of these Purifi drivers.  In my opinion, they represent the greatest advance in driver technology in the twenty years we have been designing speakers.  Highly recommended!

- Jim

[Boybees]

"In my opinion, they represent the greatest advance in driver technology in the twenty years we have been designing speakers."

Jim, you've talked about the low-distortion performance of the the Purifi drivers, and the long-throw design that permits them to move more air for a given cone diameter. I'd be curious to hear more about specific aspects of Purifi drivers that make them so special. For example, are the magnets and coils innovative in some way? What about the other materials used in the cones and surrounds?

Thanks, Dave

[TomS]

... It should result in a compact design that would work well for home theater and could be used for all front three speakers.

I'm sure these will be fantastic. What are the approximate dimensions (as in "compact")?

[jsalk]

"In my opinion, they represent the greatest advance in driver technology in the twenty years we have been designing speakers."

Jim, you've talked about the low-distortion performance of the the Purifi drivers, and the long-throw design that permits them to move more air for a given cone diameter. I'd be curious to hear more about specific aspects of Purifi drivers that make them so special. For example, are the magnets and coils innovative in some way? What about the other materials used in the cones and surrounds?

Thanks, Dave

Dave -

I'm not a driver designer.  So I don't know all the details in terms of what Purifi did to achieve their low distortion levels.  Yes, they are long-throw drivers and that is responsible for the bass extension.  But even if they didn't play all that low, it is the distortion levels that make these drivers great.

We were at an audio show when we introduced the BePure 2's.  Some young guys came out of the room saying the speakers sounded fabulous, but we must have over-driven them at some point because the surrounds were destroyed.  So at the next show, I made a little sign that said the woofers were not damaged.  That sign actually drew attendees into the room to see what a "not damaged" woofer looked like.

I'm sure if you looked a the Purifi site, you'd probably find some documentation on what else they did to reduce overall distortion.  But talking the time to deal with what little distortion is caused by a woofer surround should give you some idea of the work they put into the rest of the driver.  All I know is what I hear and it is ground-breaking.

- Jim

[jsalk]

I'm sure these will be fantastic. What are the approximate dimensions (as in "compact")?

The smaller center channel will be 8" tall, 20" wide and 10.5" deep.

- Jim

[Boybees]

We were at an audio show when we introduced the BePure 2's.  Some young guys came out of the room saying the speakers sounded fabulous, but we must have over-driven them at some point because the surrounds were destroyed.  So at the next show, I made a little sign that said the woofers were not damaged.  That sign actually drew attendees into the room to see what a "not damaged" woofer looked like.

The shape of the surrounds is the most striking visual detail of the Purifi drivers. What's fascinating is that it is a design improvement that allows the driver to perform better, but it looks to the naive observer like a "damaged" component. Usually, a design improvement in a machine causes the machine to appear more organized, more orderly, whereas this one causes the driver to appear "messier".  Not in an unattractive way, mind you, but more in a way that provokes the curiosity of the observer . . . Part of that is because the eye expects symmetry in a driver, and what we initially perceive in these drivers is a lack of symmetry.

[rowdyrobot]

If Jim is ok with posting this external link… this June 2020 review / interview describes some of the design features resulting in the Purifi driver’s performance.
https://www.soundstagehifi.com/index.php/opinion/1420-purifi-audios-pint-sized-powerhouses

P.S. I don’t want to derail this thread, but the article also praises their new-at-the-time class D amp module, which I’m also a big fan of (from experience with a VTV product). I have nothing against class A, A/B or tubes.

[jsalk]

If Jim is ok with posting this external link… this June 2020 review / interview describes some of the design features resulting in the Purifi driver’s performance.
https://www.soundstagehifi.com/index.php/opinion/1420-purifi-audios-pint-sized-powerhouses

P.S. I don’t want to derail this thread, but the article also praises their new-at-the-time class D amp module, which I’m also a big fan of (from experience with a VTV product). I have nothing against class A, A/B or tubes.

rowdyrobot -

Thanks for posting that. Much appreciated.

- Jim

[Boybees]

As Jim suggested, the Purifi website provides lots of detail about the design elements of these drivers. You can browse through the "Transducers" section to learn more. I'm not sure which model number Jim is using for the Salk speakers, as there are several that look similar to the ones in the BePure photos.

- Dave

[oskar]

The shape of the surrounds is the most striking visual detail of the Purifi drivers. What's fascinating is that it is a design improvement that allows the driver to perform better, but it looks to the naive observer like a "damaged" component. Usually, a design improvement in a machine causes the machine to appear more organized, more orderly, whereas this one causes the driver to appear "messier".  Not in an unattractive way, mind you, but more in a way that provokes the curiosity of the observer . . . Part of that is because the eye expects symmetry in a driver, and what we initially perceive in these drivers is a lack of symmetry.

I was curious so I looked it up and found this:

[lewdogg]

Oooh! Where will these land in the price hierarchy?

[Mudslide]

Jim, is the smaller center a 3-way?

[jsalk]

Jim, is the smaller center a 3-way?

No, it is a 2-way.  There is no way to make a small 3-way using Purifi drivers.  But the drivers are so clean and play so deep for their size, that in most applications, a 2-way center will work just fine.

- Jim

[redskinsfan]

Hi Jim,
When might we see the new center BePure center channels make their way onto the web site with pics and specs?

[JLM]

Here's a link to the 8 ohm version of the 6.5 inch Purifi driver (listed at $439 USD):

https://www.madisoundspeakerstore.com/approx-6-7-woofers-purifi/purifi-audio-ptt6.5x08-nfa-01-6.5-woofer-8-ohm/