It’s a baffle effect.
The same phenomenon exists in other manufacturers data sheets.
To avoid baffle effects you need to take a nearfield eg. 15mm measurement, or a truely infinite baffle.
Thanks! I am investigating why the sensitivity is different from the 2.83Vrms graphs
Our chamber has infinite baffle in the sense that you take a full 4pi chamber and cut in half and put a wall/baffle in the cut plane
When clicking here:
https://ptt.purifi-audio.com/web/content/product.template/1950/x_studio_data_sheet?download=1
you got a pdf with the following name: "PTT8.0X04-NAB-02" instead of "PTT10...."
The file name is correct when I download. There was an error that has been corrected a while back. maybe there are still old versions in a cache somewhere?
In any case, the level of 2nd and 3rd HD below 60 Hz is really impressive. It would be impressive on a 18" pro subwoofer, but on a 10" it is amazing.
Big hiatus but I am back. Way back (around posts 700) I built a pair of closed aluminium enclosures as mini monitors and housed a pair of 8 ohm 6.5" Purifi's with electronic crossovers and 15" subs. Remember them? The subs are slot ported and the integration is not perfect. I love the little monitors though. I now wish to build it into a good 3 way system and thinking sealed sub enclosures. Any recommendations for drivers? Any of the larger Purifi drivers candidates? My knowledge of the recent releases is pretty limited and there are thousands of posts since I was active. Ant info ideas appreciated.
Would you be interested in sending me a sample for distortion measurements?
Test procedure / program would be the same or similar to my recent evaluation of the Bliesma T25B-6 in 6,5" waveguide - which it would also be a good comparison object for: https://www.diyaudio.com/community/...r-cnc-3d-printing.318190/page-91#post-7412243
I had planned to visit Purifi HQ in Denmark in April, beg/borrow/steal a pair, then ship it to Ukraine ATTN: @HiFiCompass.
But damnit I was thwarted by logistical disruptions. Hopefully it will enter mass production in 2024 and we can all get our grubby paws on them.
But damnit I was thwarted by logistical disruptions. Hopefully it will enter mass production in 2024 and we can all get our grubby paws on them.
we dont have prototypes to spare at the moment (all four assembled are in the spk16 boxes). The parts for mass production are getting tooled now so we all have to be patient for a while 😀 We will of course send samples to @HiFiCompass
Hello @lrisbo,
Why did you select "Ultra Wide" coverage for the tweeter? Is it the nature of the beast or a design target?
With a wide coverage tweeter the crossover frequency to the mid-woofer will be relatively low if the coverage angles of the drivers have a smooth Directivity Index transition.
The listening position will need to be close to keep the direct sound louder than the room surface reflections.
I have a pair of BlieSMa T25A-6 Aluminium-Magnesium Dome Tweeter Matched Pair being delivered in a couple of days for a test drive.
Thanks DT