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NEW PURIFI 8'' MWoofer [PTT8.0X04]

D!sco

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Do you know Troels' SEAS-based JA8008-HMQ?

The distortion is higher than purifi's standards, but otherwise it looks pretty good.

The older version was measured by Zaph:
I was always curious about a third party measurement on this driver. Seems pretty good tbh. It's already almost at 98dB so I can't imagine much additional distortion with rising volume. And at that sensitivity there are some tweeters that won't even need padding to operate correctly. Damn.
 

AlexScan

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Review by HifiCompass : "It is the best aluminum cone 8" midwoofer I've ever heard."


ptt8.0x04-nab-02_side2.jpg
 

NYfan2

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Review by HifiCompass : "It is the best aluminum cone 8" midwoofer I've ever heard."


ptt8.0x04-nab-02_side2.jpg
The only downsize is the price, € 699,95 here in Europe.
 

Rick Sykora

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mocenigo

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Purifi updated their website, the spec sheet is now downloadable, and the status of this driver is now 'new' instead of 'preview'.

Maybe we can see this being tested in the future? @hardisj

Imagine a floorstand/big monitor with 2x this and a well-designed tweeter :)
PTT8.0X-front-perspective-trans-440x440-1-315x315.png

PTT8.0X04-NAB-01-SPL_2.83Vrms_F2.png

2x this; their 4.5”, and an AMT as tweeter. Would be expensive to build, but it would probably be endgame.
 

Digital_Thor

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2x this; their 4.5”, and an AMT as tweeter. Would be expensive to build, but it would probably be endgame.
Not the current 4,5" but a real dedicated 5" midrange, so that we can have a great power response and sensitivity
:D

With expensive and great drivers... I really do not want to compromise with dispersion in the cross over region where our hearing is most sensitive
 

intaud

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I'm thinking of building a 2-way with this driver and a Tectonic BMR. I would crossover around 500Hz. A sealed enclosure to keep it fairly compact and a MiniDSP Flex for the crossover and EQ.
 
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Lars Risbo reported that the Purifi 8" was in a ported 32L box tuned to 28Hz as shown below in the pic and link. The Mundorf AMT25CS tweeter and custom waveguide was paired with the speakers at the factory. Heard a rumor Purifi may launch a tweeter in a year or so. Lars Risbo inidicated that these speakers imaged very well in the near field at 3-4 meters. They look interesting for DIY'ers that want a simple square box, at a size range of 30-50L which I think is popular size for DIY, and something that is full range.

It seems like this would be a next step for an ASR speaker project that pushes performance even higher? Why not a cost no object approach on drivers and see what you can do? I am curious about a high end JBL clone with the best compression driver mated to the 8 inch Purifi mid woofer.


Link from DIY Audio. Rasmus Larsen tour of Purifi Audio. Pretty cool story to hear about the evolving drivers from Purifi.


1670006638175-jpeg.1115978
 

witwald

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Lars Risbo reported that the Purifi 8" was in a ported 32L box tuned to 28Hz as shown below in the pic and link. The Mundorf AMT25CS tweeter and custom waveguide was paired with the speakers at the factory. Heard a rumor Purifi may launch a tweeter in a year or so. Lars Risbo inidicated that these speakers imaged very well in the near field at 3-4 meters.
Those speaker enclosures were very reminiscent of BBC monitor designs. And if they imaged very well, they may have done so, but not actually in the near field. A listening distance of 4 meters is many times the largest dimension of the enclosure, so listeners are more or less in the far field by then, aren't they?

The speakers were also described as being designed so that their "FR was tuned flat at 30 [degrees] off axis." Wouldn't this imply that the on-axis response may have a noticeable lift in some frequency bands. Or am I missing something?

Maybe this loudspeaker has been created to be listened to when the listener is significantly off-axis, while radiating non-flat sound energy levels into the room when measured on-axis? Wouldn't that go some way to explaining those "good" imaging characteristics?
 
Last edited:

witwald

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Review by HifiCompass : "It is the best aluminum cone 8" midwoofer I've ever heard."

However, the on-axis frequency response measurements of this aluminum-coned midwoofer do seem to show the now traditional sharp high-Q metal-cone breakup modes. The BBC worked hard all those years ago to try and tame driver resonances of this very type. Maybe it was those same resonances that transformed this midwoofer into the "best aluminum cone 8" midwoofer I've ever heard" on a subjective, not objective, basis?
 

witwald

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Review by HifiCompass : "It is the best aluminum cone 8" midwoofer I've ever heard."

The review mentions a new audio term when describing the step response of the driver: "monotonous decay". Can someone provide an exposition of what it means? ;)

In any case, the "wiggly" step response is hardly exemplary, as it's heavily adulterated by high-frequency oscillations:
https://hificompass.com/sites/default/files/zamer/stepresp/ptt8.0x04-nab-02_step_response.png
 

SDC

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Lars Risbo reported that the Purifi 8" was in a ported 32L box tuned to 28Hz as shown below in the pic and link. The Mundorf AMT25CS tweeter and custom waveguide was paired with the speakers at the factory. Heard a rumor Purifi may launch a tweeter in a year or so. Lars Risbo inidicated that these speakers imaged very well in the near field at 3-4 meters. They look interesting for DIY'ers that want a simple square box, at a size range of 30-50L which I think is popular size for DIY, and something that is full range.

It seems like this would be a next step for an ASR speaker project that pushes performance even higher? Why not a cost no object approach on drivers and see what you can do? I am curious about a high end JBL clone with the best compression driver mated to the 8 inch Purifi mid woofer.


Link from DIY Audio. Rasmus Larsen tour of Purifi Audio. Pretty cool story to hear about the evolving drivers from Purifi.


1670006638175-jpeg.1115978


A member from S.Korea made a visit and posted too.

He owns t25b-6 and m74b-6, after the tour he is worried BlieSMa won't be end game after listening to purifi speakers!

And Purifi launching tweeter is not just a rummor but it is delayed and delayed we don't know if it will be done in a year...
 

Rick Sykora

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Link from DIY Audio. Rasmus Larsen tour of Purifi Audio. Pretty cool story to hear about the evolving drivers from Purifi.


1670006638175-jpeg.1115978

A few observations that escaped me initially (as was drooling over speakers):
  1. Am thinking this is a very lively room. The rug looks as though it was bought cause the floor was too cold for the dog! :D
  2. The bigger speakers seem quite far apart...
  3. The right one seems too close to the side wall to avoid early reflections...
  4. Would expect the front of all the speakers to be the same distance from the front wall (rather than the backs)!:eek:
  5. Lots of beefy passive crossover boards on the floor except for the one on top of the right SPK6.
  6. I see lots of amplifiers but not sure what else. Anybody recognize the little boxes in the back right?
This could be one of the worst examples of a listening room layout that I have seen. I do have some equipment envy though! :)
 
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A few observations that escaped me initially (as was drooling over speakers):
  1. Am thinking this is a very lively room. The rug looks as though it was bought cause the floor was too cold for the dog! :D
  2. The bigger speakers seem quite far apart...
  3. The right one seems too close to the side wall to avoid early reflections...
  4. Would expect the front of all the speakers to be the same distance from the front wall (rather than the backs)!:eek:
  5. Lots of beefy passive crossover boards on the floor except for the one on top of the right SPK6.
  6. I see lots of amplifiers but not sure what else. Anybody recognize the little boxes in the back right?
This could be one of the worst examples of a listening room layout that I have seen. I do have some equipment envy though! :)

These Danes at Purifi are arguably the leaders in driving the state of the art, and its pretty nice that they are sharing bread board mockups with visitors and maybe they do put out a rug for the shop dog? Those floors do look cold. ;)

Maybe the little boxes in the back right are some music sources in digital storage? Purifi and Hypex are the top dogs of digital after all. No vinyl or CD's are lying around and they have a fancy Mola Mola dac in the center.

This thread is about the PTT8. Do you think the Mundorf AMT25CS is the best possible companion for the PTT8 mid-woofer? Would you go 2 way or do you think you could get more performance from a 3 way? These are expensive drivers, but if you dream about having SOTA drivers it seems like you should just make an all out assault on performance and get the best drivers you can, with the only constraint being reasonable size like 50 liter boxes and being easy to build? I have a big room and occasionally listen at rock concert levels in the mid-field so I am looking for something with some oomph.

Below is another take on a PTT8 speaker. May have already been posted. It's interesting that it is horn loaded. I would be really interested to know what Lars Risbo thinks is the best set up is for this new driver, I assume it is the Mudorf AMT tweeter.

 

fcracer

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Purifi updated their website, the spec sheet is now downloadable, and the status of this driver is now 'new' instead of 'preview'.

Maybe we can see this being tested in the future? @hardisj

Imagine a floorstand/big monitor with 2x this and a well-designed tweeter :)
PTT8.0X-front-perspective-trans-440x440-1-315x315.png

PTT8.0X04-NAB-01-SPL_2.83Vrms_F2.png
Still looks ugly but I think someone can include these in a retro design that uses speaker grills as part of the aesthetic. Super modern internals + nostalgic design = winner.
 

fineMen

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Still looks ugly but I think someone can include these in a retro design that uses speaker grills as part of the aesthetic. Super modern internals + nostalgic design = winner.
Once one understands why the surround has this particular shape, true love is there, and vice versa disregard for all the other. Simple.

Should be ten pcs. to match surface area of two 18"
2pcs 8inch from SB Acoustics for bass plus another for mids would replace a P/ 8inch for less than half the cost. WIth more flexibility. Enclosure size? Think of how to craft a port that would take the airspeeds to occur. A drone--the dynamic weight. Sealed--loss of max output.

The driver is for sure a (very) big achievement, but a niche product still.
 
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