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

[Kaladin]

Awesome work. How are you dealing with the differences in interior volume and other variables the plate amp is introducing to the spk16 design? Lots of work and I commend you for doing so.

Interior volume and most of the geometry stays the same. The cabinet extends back further with a chamber for the plate amp.

Other than that it will just be measuring and refining.

 

[Salt]

Whatever amp the sub manufacturer used.
Have you ever seen a separate manufacturer for a subwoofer plate amp?

Hypex, Dayton, ,...

 

[bmc0]

Open to your wisdom on best path forward at that point.

All my speakers are my own design with separate electronics. Basic signal flow: software DSP (on a Raspberry Pi) → audio interface → four power amps (10 channels total) → speakers. I'm certainly not one to argue for integrated, proprietary solutions in general .

With switching power supplies and Class D amplifiers, the frequency load on the capacitors is, in most cases, the decisive factor for their lifespan.

Do you have any references for this? Losses are higher at high frequency, leading to higher operating temps. In a brief search, I didn't see any mention of the influence of frequency on life except for its effect on operating temperature.

 

[Marin]

head shadowing

Can you explain this to me or point me to a link?
This is the first time I hear about this.
Thanks!

 

[jhaider]

Can you explain this to me or point me to a link?
This is the first time I hear about this.
Thanks!

The HF wavelengths are so short that your head will block many of the reflections that make it. So a wider top octave doesn’t make things “bright” so much as just IMO improves the size of the seating area that receives the intended spectral balance.

 

[srekal34]

The HF wavelengths are so short that your head will block many of the reflections that make it. So a wider top octave doesn’t make things “bright” so much as just IMO improves the size of the seating area that receives the intended spectral balance.

It depends on a personal preference.
I have speakers with Bliesma t34a which have super wide dispersion and listening to it in an untreated room is quickly tiring.

 

[Lars Risbo]

are you sure the tiring is caused by the dispersion pattern?

 

[Paul7777x]

This may seem bizzare, but can some who understands how to do so, colour in this timber finish in a satin black for me pretty please?

I just can’t adequately picture it in my head.

I know it’s possible with some form of sorcery, but that’s all I know.

Thank you.

 

[Matias]

Gemini: loudspeaker, paint the chassis in matte black.
Voila.

 

[Paul7777x]

Gemini: loudspeaker, paint the chassis in matte black.
Voila.

View attachment 519384

Utterly Magnificent!!

Thank you sir.

You are my new superhero

 

[Roland68]

This may seem bizzare, but can some who understands how to do so, colour in this timber finish in a satin black for me pretty please?

I just can’t adequately picture it in my head.

I know it’s possible with some form of sorcery, but that’s all I know.

Thank you.

View attachment 519378

Since it's MDF, it's very easy.
It's even easier if you build the enclosure directly with black-dyed MDF.

The following doesn't work with the Valchromat panels discussed here:
You can treat the surface with oil, wax, and various stains (not varnish). Such products are also available pre-tinted and safe for indoor and kitchen use. Some are even completely organic.
These products are usually available in matte and glossy finishes.
You can also change the degree of matte finish by lightly roughening the surface with steel wool.
The advantage is the surface's durability and ease of repair. The disadvantage is the need for precise assembly, as no filler can be used.

The following also works with Valchromat panels:
The fourth, more exclusive option would be a professional epoxy resin finish, which can also be matte if desired. A slight pre-tinting of the epoxy resin also creates a certain sense of depth.

The same applies to metal flake paint finishes.

 

[Penelinfi]

Gemini: loudspeaker, paint the chassis in matte black.
Voila.

View attachment 519384

It even gave it a dining table crescent edge

 

[Marin]

The HF wavelengths are so short that your head will block many of the reflections that make it. So a wider top octave doesn’t make things “bright” so much as just IMO improves the size of the seating area that receives the intended spectral balance.

Yes, I completely agree with you.
I just heard that term for the first time.
I probably can't even hear that highest octave since I'm in my fifties, like many people here.
To me, the "brightness" comes from the increased frequency response in range of 3 000-8 000Herz range.
I also don't know how useful it is considering it reduces sensitivity of twiter, since energy is redirected to the side?
Not to mention that you can't control how bright the sound you want simply by toe in-out...

 

[Paul7777x]

Anyone built, or had built, a pair of cabinets yet?

Still haven’t heard from the CNC place…

 

[Kaladin]

The cabinet designed for heat set inserts with a Hypex plate amp. It’s a FA253 since that’s what I happened to have on hand. I’ve intentionally left out the pass through from the amp cabinet to the drivers to be drilled out after filling and assembling the cab.

The assembly mock ups actually have a 6.5 woofer in place of the passive radiators. I was having trouble with the PR 3D model file on Purifi’s website downloading without an extension.

 

[Paul7777x]

The cabinet designed for heat set inserts with a Hypex plate amp. It’s a FA253 since that’s what I happened to have on hand. I’ve intentionally left out the pass through from the amp cabinet to the drivers to be drilled out after filling and assembling the cab.

The assembly mock ups actually have a 6.5 woofer in place of the passive radiators. I was having trouble with the PR 3D model file on Purifi’s website downloading without an extension.

Looking good.

 

[Chaos01]

Anyone built, or had built, a pair of cabinets yet?

Still haven’t heard from the CNC place…

I asked 3 CNC companys, one cant help me for the next 5 month because of other work, one just sayed no, cant help and one did not replyed yet, still waiting. It seems to be Not that easy to find someone and i have no idea about a Price yet.

Im curious about the flat pack Purifi mentioned. Wondering about the possible Price.

 

[Paul7777x]

I asked 3 CNC companys, one cant help me for the next 5 month because of other work, one just sayed no, cant help and one did not replyed yet, still waiting. It seems to be Not that easy to find someone and i have no idea about a Price yet.

Im curious about the flat pack Purifi mentioned. Wondering about the possible Price.

I get the same impression. Too small a job perhaps?

Looks like it might be the flat pack if it comes to that.

 

[Lars Risbo]

the cabinet option we will offer is not a wooden flatpack but a cabinet molded in a stone composite material. we showed these at Munich 2025.

 

[Matias]

Lars, any chance you guys at Purifi could print Caladin's design to test and validate, possibly even measure?