I have exact that MW13TX and 6.5x.... I'll return with my findings.
Is your T25B 'naked' or with a WG?
I didnt understand what you are trying to say making fun of me or what.... I have not made cabinet cause need input what info i have is Jospeh crow 2 way purifi and on Purifi site speaker planWould you accurately state make and model of the drivers you own and measures of cabinet you find suitable for these?
It does not matter how large a container is, it matters the quality of stuff it's filled with! It can be anything.
Thank you for the reply I know what you say since I am not able to do as I mentioned clearly thats why have come to this forum. thanks anyway lets see ifthere is 1 chap here who can share his build. 2 days still no one sent or positive reply. What can I say of this community
If there are reliable measurements I think there are many people here that can help with the modeling. Should not be a problem.
~30L PR setup.Closed, br, passive drivers? How many liters?
Because I tried the same in both 30 and 60 liters closed, and found them less 'punchy' than a pair of sb23nrx. I can only think that it is lack of surface area.... Or else I don't understand my findings
I doubt it's necessary, but I'd strongly prefer not using a waveguide on the T25B and the directivity and distortion profiles of the 2 indicate that adding one might result in a better speaker.
That would be great. I'm primarily interested in subjective reactions (I've got measured data from Hifi Compass). I'd prefer no waveguide. BTW, the alternative to using the MW13TX, currently, is the PTT5.25 or, perhaps, the M74A (I can't afford the M74B).
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I assume the plans are for the drivers you currently have. If you can share the specifications of the crossover in those plans (frequencies, filter types) someone can probably plug those into the miniDSP software for you. Unfortunately I don't have any MiniDSP stuff so I can't personally help with this.
Here is an animation of Comsol simulations of a 5.25" driver with our strange surround and a std. half roll. The cone is reproducing a 1/4Hz sinusoidal motion with amplitude of 11mm. The graph shows the relative modulation of the total radiating surface area (aka Sd(x)). For example, 10% deviation causes a 10% change of the sound pressure (Being proportional to Sd) which manifest itself in 10% amplitude modulation of any higher frequency signal superimposed. In other words 10% IMD. The new surround keeps that modulation at a fraction of a percent.
Cheers,
Lars @ Purifi
Cheers,
Lars @ Purifi
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So... as a midrange driver, where the p-p is maybe 1/10mm ( 3 way). It almost vanishes? But as a woofer/midrange combined (2 way) - it's a big deal?
Yea, @digitalthor, that's the premise. It's what gives it so much value in broad operating ranges. That way it can operate far lower than previously feasible at high SPL while still producing higher notes at no variation. Simplifies your directivity and crossover a lot. Just consider the expense of some three-way nets compared to the increased price of a purifi woofer. Using a Purifi woofer as two of the ways in a three way makes less value sense, but it's still quite good in theory. They are tonally similar and hold similar properties. Something like a TMWW would still greatly benefit from the low distortion at all ends of the spectrum. The proposition of value always looms large, however, and the surround does not appear to add much value in the mid as you suggest.
There is a report on The Loudspeaker Project Pad page on Facebook by Rasmus Munk Larsen who visited the Purifi factory recently. Of interest to this group is a prototype using the 8” and an AMT in a waveguide. Rasmus really liked these. Can @lrisbo give any more detail or confirm if they will be available as a plan/kit etc.
With that much excursion capabilities and the given T/S-parameters, that cabinet size and shape seems to be well suited to fully exploit the driver and match it to the wave-guided tweeter.
PR is always a compromise IMHO, to realize small enclosures.