PURIFI finally did a fully purified passive speaker design! The SPK 16 prototype is here - with a PTT tweeter

[jaakkopetteri]

You can always make your own coax with the tweeter of your choice..

I guess you can ultimately make anything "yourself" if you have the dough, but in practice it's not that simple considering you'd ideally match the cone curvature to the tweeter specifically and so on

 

[Roland68]

You can always make your own coax with the tweeter of your choice..

It's not that easy to build a well-functioning coaxial chassis, no matter how you do it. I've heard a lot of coaxial chassis and a few speakers with them, and very few of them were good or even convincing, regardless of the price.

Exciting, I’ve been waiting what feels like an eternity for an update on the SPK16

We've been waiting almost 1 1/2 years for real updates.
I listened to the speaker at the High End in Munich this year and went back one day at the end when the hall was quieter.
The speaker is anything but bad, but it didn't blow me away either. I'm excited to see if that changes in a future version.

 

[Matias]

The way it has been going, by the time the tweeter is finished and the design ready, there will be already dozens of 2 way bookshelf speakers using Purifi woofers and PRs. Right now: March, AsciLab, Radiant, Buchardt, Immsine, Lyngdorf, YB, and counting...

 

[ayane]

The speaker is anything but bad, but it didn't blow me away either. I'm excited to see if that changes in a future version.

The SPK16 isn't supposed to be a mind-blowing speaker. It's Purifi's reference implementation of their in-house drivers via a simple 5th order 2-way design in a well-engineered box. The constant directivity tweeter and low distortion woofer themselves are the stars of the show; they can be incorporated into "fancier" designs utilizing cardioid loading, force-balancing, etc. The only things to write home about are the low distortion and the well-controlled directivity (at least above 2 kHz, if Purifi's white paper reflects the measured performance of the PTT1.3 tweeter).

Both are significant feats of engineering even if their importance or desirability is controversial. Even though distortion isn't considered as important as on- and off-axis response, it is the ultimate limiting factor in fidelity on the reproduction side, because the transducer itself adds orders of magnitude more distortion than any electronics up the playback chain. Constant directivity would result in flat in-room sound, which may be preferred less than a tilting in-room response, but the tweeter being able to control its beamwidth over one decade (2-20 kHz) would still be extremely versatile for HiFi applications.

 

[Head_Unit]

Exciting, I’ve been waiting what feels like an eternity for an update on the SPK16

Yes...I keep picturing a slim ported mini-tower. Then again I keep dreaming of something with high sensitivity...hopefully to come...

 

[Rick Sykora]

Seem to keep forgetting Audioholics 2023 Product of the Year - The Philharmonic BMR HT tower.

 

[Everett T]

It's not that easy to build a well-functioning coaxial chassis, no matter how you do it. I've heard a lot of coaxial chassis and a few speakers with them, and very few of them were good or even convincing, regardless of the price.


We've been waiting almost 1 1/2 years for real updates.
I listened to the speaker at the High End in Munich this year and went back one day at the end when the hall was quieter.
The speaker is anything but bad, but it didn't blow me away either. I'm excited to see if that changes in a future version.

I'd beg to differ, if that was your goal as it isn't rocket science and is more common than one might think

 

[Dennis Murphy]

Seem to keep forgetting Audioholics 2023 Product of the Year - The Philharmonic BMR HT tower.

Thanks. We just heard from Purifi today stating that the tweeter is almost ready to ship. It will certainly be interesting to test out, and I have a few ideas on implementation if it lives up to expectations.

 

[Paffi]

Seem to keep forgetting Audioholics 2023 Product of the Year - The Philharmonic BMR HT tower.

oh wow, thank you for that - didn´t notice this speaker yet. Asked a local hifishop about philharmonic and they said something blabla only for classic music blabbla not so good haha. Another speaker for audition list, just hard to find any dealer...

 

[Roland68]

oh wow, thank you for that - didn´t notice this speaker yet. Asked a local hifishop about philharmonic and they said something blabla only for classic music blabbla not so good haha. Another speaker for audition list, just hard to find any dealer...

I would strike the dealer off my list, he obviously has no idea what he's doing or he's trying to sell you something else and is badmouthing a good product.

 

[JohnnyNG]

Thanks. We just heard from Purifi today stating that the tweeter is almost ready to ship. It will certainly be interesting to test out, and I have a few ideas on implementation if it lives up to expectations.

An all-Purifi Philharmonic 3-way! One can dream.

 

[Roland68]

I'd beg to differ, if that was your goal as it isn't rocket science and is more common than one might think

Then we probably have different experiences and different opinions.
For me, the prerequisite is that the loudspeaker with a coaxial chassis not only measures well, but also sounds good and is fun. This was usually not the case even with more expensive and hyped coaxial chassis. Either my expectations are too high, or I haven't heard the right coaxial driver yet.

In any case, I'm really excited about the new one from Purifi.

 

[jaakkopetteri]

Then we probably have different experiences and different opinions.
For me, the prerequisite is that the loudspeaker with a coaxial chassis not only measures well, but also sounds good and is fun. This was usually not the case even with more expensive and hyped coaxial chassis.

Getting off-topic, but which have you heard?

 

[Dennis Murphy]

An all-Purifi Philharmonic 3-way! One can dream.

I think Purifi would need to come up with a small midrange that has higher sensitivity than their current offerings. I know that watts are cheap, but low sensitivity is a hard sell for HT applications, and that's where an increasing amount of the action is.

 

[Ktacos]

The way it has been going, by the time the tweeter is finished and the design ready, there will be already dozens of 2 way bookshelf speakers using Purifi woofers and PRs. Right now: March, AsciLab, Radiant, Buchardt, Immsine, Lyngdorf, YB, and counting...

I'd take this purifi design over all of these. Most waveguides of this size are far more narrow than the purifi for example, not really any waveguides that go this low and are still wide through the whole range.

But the aspect that's gonna push it beyond the others are the big round overs. There is a smoothness and clarity to the sound of a speaker with big round overs that I feel really puts a speakers in a category of its own. Having experimented with everything from a hard 90 degree edge to 3 inch radius round overs, I'm finding it to be a problem that is overlooked and it's hard to listen to speakers without big round overs now.

 

[ayane]

But the aspect that's gonna push it beyond the others are the big round overs. There is a smoothness and clarity to the sound of a speaker with big round overs that I feel really puts a speakers in a category of its own. Having experimented with everything from a hard 90 degree edge to 3 inch radius round overs, I'm finding it to be a problem that is overlooked and it's hard to listen to speakers without big round overs now.

I wouldn't be so sure about this. Roundovers definitely help with diffraction, but with narrow baffles, you push the frequencies where diffraction becomes a problem into the octaves where the sound is already directional, especially so with a wide waveguide. A bigger baffle with gentle roundovers may give you some efficiency gains at mid-low frequencies (by pushing the baffle step loss lower) but to say that lacking these features makes a speaker "hard to listen" seems hyperbolic. We're talking about variations that are hardly ±1 dB if that.

Take the Buchardt A10 or KEF R3—both are great examples of the narrow baffle/wide waveguide approach, and they are among the best measuring speakers in the world.

 

[boXem]

I'd take this purifi design over all of these. Most waveguides of this size are far more narrow than the purifi for example, not really any waveguides that go this low and are still wide through the whole range.

At least Ascilab and Radiant have waveguides aiming for wide directivity at HF.
BTW, the Radiant waveguide seems to be designed by Lars Risbo, the guy behind the SPK16.

 

[pLudio]

BTW, the Radiant waveguide seems to be designed by Lars Risbo, the guy behind the SPK16.

 

[Ktacos]

I wouldn't be so sure about this. Roundovers definitely help with diffraction, but with narrow baffles, you push the frequencies where diffraction becomes a problem into the octaves where the sound is already directional, especially so with a wide waveguide. A bigger baffle with gentle roundovers may give you some efficiency gains at mid-low frequencies (by pushing the baffle step loss lower) but to say that lacking these features makes a speaker "hard to listen" seems hyperbolic. We're talking about variations that are hardly ±1 dB if that.

Take the Buchardt A10 or KEF R3—both are great examples of the narrow baffle/wide waveguide approach, and they are among the best measuring speakers in the world.

Dispersion charts show diffraction issues on those speakers from their edges.

Compare them with the theory audio speaker reviewed recently that have big round overs, or kii three which has its diffraction artifacts down in the 1k range. I should note I'm talking about edge termination not baffle size. Want a bad example, css criton.

 

[Ktacos]

At least Ascilab and Radiant have waveguides aiming for wide directivity at HF.
BTW, the Radiant waveguide seems to be designed by Lars Risbo, the guy behind the SPK16.

You still need to terminate the edges of waveguided speakers with round overs, have plenty of my own data showing the benefits. Joseph crowe is a speaker designer who does waveguides/horns and his take it a step further and round all the way to back of the horn mouth.

This format of 6.5" woofer with 6" ish waveguide is pretty common anymore, so one needs to really do all they can to optimize other aspects like cabinet geometry. Some companies put a lot of effort into eliminating diffraction and it's worth it imo. I don't even look at speakers with hard edges anymore because the big round overs just sound so much smoother. I believe Bruno putzeys shares a similar opinion seeing as all his speaker max out their round overs for the given box dimension.