Exactly this, or the directivity.
I understand that for some people it can be a bit scary to mess around with some speakers.
But first of all there are alternatives, second if we're spending a good amount anyway, I would pay a professional to do these tweaks for me.
At this point it feels a bit like a no-mans-land choice.
With no disrespect btw, I mean if you're happy with it and it sounds incredible to you, happy days!
Anyway, totally off-topic, sorry.
IMO the 6.5 is nearly as powerful as a typical 8. Nothing wrong with using the 6.5 from fs to baffle step, onto a mid then tweet. (should) Avoid the port resonance issue too.
I agree with Hifijim and b_force, who have politely stated what experienced designers are implying.
I have a 2 way design with the PTT6.5X with a 1” dome tweeter sans waveguide. And the horizontal dispersion is nice and smooth out to 90 degrees. You can achieve this with consideration of baffle shape/dimensions, driver placement in the baffle, centre-to-centre spacing, and the interplay of the crossover frequency and slope.
I’ll been reluctant to show the measurements online because they are from an ugly prototype cabinet, and is not the final design.
I’ll have to dig it out somewhere.
IMHO the PTT 6.5X or W Is ideally suited for compact 2 ways; you don’t really need to add a midrange in there when the 500-2KHz response is soo smooth, with none of the cone-suspension edge related resonances.
also I agree with mainframe99 that the PTT6.5X is better than many 8” midwoofers. So if you’re having some bass issues I’d check your alignment and room/interface
I have a 2 way design with the PTT6.5X with a 1” dome tweeter sans waveguide. And the horizontal dispersion is nice and smooth out to 90 degrees. You can achieve this with consideration of baffle shape/dimensions, driver placement in the baffle, centre-to-centre spacing, and the interplay of the crossover frequency and slope.
I’ll been reluctant to show the measurements online because they are from an ugly prototype cabinet, and is not the final design.
I’ll have to dig it out somewhere.
IMHO the PTT 6.5X or W Is ideally suited for compact 2 ways; you don’t really need to add a midrange in there when the 500-2KHz response is soo smooth, with none of the cone-suspension edge related resonances.
also I agree with mainframe99 that the PTT6.5X is better than many 8” midwoofers. So if you’re having some bass issues I’d check your alignment and room/interface
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It's more the combination of things.
One would go for a real mid to go for a very omni directional kind of speaker.
In that case, a 25mm tweeter isn't really the best choice, I would rather advice for a smaller tweeter.
With a 25mm there isn't much to win, plus there might be even a discrepancy in directivity.
Than there is directivity and reflections in a certain room.
A 2-way 6.5inch plus waveguide is quite a decent compromise not having a DI (directivity index) that's to high.
Also the crossover is a lot easier to make.
In mean in the end it's all fine if that's what he's going for.
But it's just not the most logical approach (which again doesn't mean it's wrong)
Practically I personally also think it just makes things rather complicated while there is very little to gain.
haha ,good question!
A little hard to quantify.
But to give a bit of perspective, people often find 10-15 inch beaming (way) to much.
While something like a omni directional kind of speaker can create to many room issues.
a 6.5 inch sits kind of in between the two.
I was more asking for your opinion. I understand directivity reasonably well.
I don't. My system has a Q around 12 above 300Hz or so and that's just fine. I'm not interested in hearing the room.
I’d like to see more of Lavoce drivers
Particularly the
WAN102.50LD
Woofer Aluminiumchassis Neo 10”,
2.50” voice coil, Low Distortion
The SAN214.50 had an excellent showing at data-bass.com.
Prices have crept up in the last 2.5 years (what hasn’t?), but still an outstanding value.
Particularly the
WAN102.50LD
Woofer Aluminiumchassis Neo 10”,
2.50” voice coil, Low Distortion
The SAN214.50 had an excellent showing at data-bass.com.
Prices have crept up in the last 2.5 years (what hasn’t?), but still an outstanding value.
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I probably agree, but I was just giving a general answer and observation.
It's always a compromise between spaciousness and detail (and practicality)
@ tktran303 and b_force
So, you hesitate between one of the fancy Bliesma domes or a fancy 6.5-incher?
You first may compare the measured data of the 3 inch bliesma m74a with the 6.5 inch purify ptt6.5w04, e.g. at 60° off-axis.
https://hificompass.com/sites/default/files/zamer/noaxis/m74a-6_offaxis_normalized_5-30db.png
https://hificompass.com/sites/default/files/zamer/noaxis/ptt6.5w04-01a_offaxis_normalized_5-30db.png
The Bliesma 3-inch dome is -1.5dB down at 2kHz and -5dB down at 3kHz, -3dB occurs at 2.5kHz
The Purify 6.5-inch cone is -3.2dB down at 2kHz and -10.5dB down at 3kHz.
Therefore, if you wish to have an even horizontal polar pattern at the crossover between midrange and tweeter, you will have to lowpass these drivers at some 2.5kHz for the Bliesma and at 2khz for the Purify.
As for the vertical pattern, the Bliesma has an outside diameter of 121mm, whereas the Purify comes with a diameter of 176mm. Choosing a Bliesma T25A tweeter with an outer chassis diameter of 68mm, you will get center-to-center distances of 95mm for the Bliesma combo, and of 122mm for the Purify combo. As for the drivers vertical interference artefacts, you may calculate for the Bliesma combo lambda_2500Hz/95mm, and for the Purify combo lambda_2000Hz/121mm. This equals 1.44 for the Bliesma combo, and 1.41 for the Purify combo. Therefore, the vertical polar behavior will be the same for both combos. At the end of the day, you will just stress the tweeter a little bit more at 2kHz xover with the 6.5-incher than with the 3-inch dome crossed at 2.5kHz.
And then you may decide upon wheter you prefere a midrange with higher sensitivity but smaller volume dispacement capacity (Bliesma: 95dB/2.83V and 12.06cm^3 linear Vd), or one with a in this respect reveresed characteristic (Purify: 88db/2.83V and 266cm^3).
For me and overall within a 3-way system, the Purify combo would make more sense because of its more than 20-fold linear volume displacement capacity compared with any of the Bliesma midrange domes.
So, you hesitate between one of the fancy Bliesma domes or a fancy 6.5-incher?
You first may compare the measured data of the 3 inch bliesma m74a with the 6.5 inch purify ptt6.5w04, e.g. at 60° off-axis.
https://hificompass.com/sites/default/files/zamer/noaxis/m74a-6_offaxis_normalized_5-30db.png
https://hificompass.com/sites/default/files/zamer/noaxis/ptt6.5w04-01a_offaxis_normalized_5-30db.png
The Bliesma 3-inch dome is -1.5dB down at 2kHz and -5dB down at 3kHz, -3dB occurs at 2.5kHz
The Purify 6.5-inch cone is -3.2dB down at 2kHz and -10.5dB down at 3kHz.
Therefore, if you wish to have an even horizontal polar pattern at the crossover between midrange and tweeter, you will have to lowpass these drivers at some 2.5kHz for the Bliesma and at 2khz for the Purify.
As for the vertical pattern, the Bliesma has an outside diameter of 121mm, whereas the Purify comes with a diameter of 176mm. Choosing a Bliesma T25A tweeter with an outer chassis diameter of 68mm, you will get center-to-center distances of 95mm for the Bliesma combo, and of 122mm for the Purify combo. As for the drivers vertical interference artefacts, you may calculate for the Bliesma combo lambda_2500Hz/95mm, and for the Purify combo lambda_2000Hz/121mm. This equals 1.44 for the Bliesma combo, and 1.41 for the Purify combo. Therefore, the vertical polar behavior will be the same for both combos. At the end of the day, you will just stress the tweeter a little bit more at 2kHz xover with the 6.5-incher than with the 3-inch dome crossed at 2.5kHz.
And then you may decide upon wheter you prefere a midrange with higher sensitivity but smaller volume dispacement capacity (Bliesma: 95dB/2.83V and 12.06cm^3 linear Vd), or one with a in this respect reveresed characteristic (Purify: 88db/2.83V and 266cm^3).
For me and overall within a 3-way system, the Purify combo would make more sense because of its more than 20-fold linear volume displacement capacity compared with any of the Bliesma midrange domes.
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Agreed. Normal use is harmless. But sooner or later you will no more be able to control for the normal use of any Be dome or structure. So it is not a concern for you personal audiophile health, but rather a matter of ecological awareness/concern wheter you will go for Be or not. MgAl instead would be of no concern altogether.
I'm glad to hear that the PTT6.5 can provide smooth transition to a 1" tweeter. I will, of course, experiment and see if a midrange is desireable, but at this point, I've been planning that it will be. I will be using CSS SDX12 subs below the PTT6.5, so an 8" isn't really needed and the 6.5 allows for a smaller enclosure (typically).
Considering WG is out of equation.....Why not T34B with PTT6.5? T34B, to my ears, does not loose anything from top end extension and airyness compared to T25B, and offers better crossover flexibility if needed. T25B struggles below 2k and I would not take it any lower with LR4 crossover. Knowing both T34B and T25B, I would suggest T34B over T25B to mate with almost any 6" mid.
It's a driver. If not abused it will likely outlive you. If it doesn't, dispose as per guidelines at the time or leave instructions for your estate to do so if it does. It's an inert substance and not particularly problematic unlike say asbestos. Audiophiles worry about a lot of pointless rubbish. Batteries, solar panels etc are likely to be many, many orders of magnitude more of a concern as they're orders on magnitude larger and more common. Then consider the disposal of the bird chomping eco-crucifixes aka windtowers; do some research on the disposal issues of those.
Buy what you want, but if you don't use Be domes for this reason then you're an overworrying fool.
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Yes, I thought hard about T34B vs. T25B, but for better or worse, that decision has been made.
Please condone a last slightly out-of-topic interjection: You are right. 100%. We live in and on an a huge, complex world, more and more out of control. Where some milligrams of Be basically do not matter.
Still, let me retire peacefully onto my overseeable, manageable and tidy audio hill and let me there enjoy my life as a true naive and happy fool. Feeling good to care for seemingly useless things.
www.youtube.com/watch?v=wsRatIMUSu8
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