restorer-john
Grand Contributor
Did you know the Q Acoustics 3050i comes in Arctic White? I bet it has a good Polar response....
But basically the possible range of dispersion patterns is baked in through the choice of driver dimensions and baffle size..?
Do you know how and why 'beaming' occurs? Look it up.I doubt it. This is basically a rehash of the idea that only the frequency response matters and the price and cone materials and other specifications don't matter. I disagree.
Phase is important, but not because phase in itself is audible. It is important because the low frequency driver and the high frequency driver must sum up correctly around the crossover frequency, where both drivers emit sound simultaneously. Any time offset between the drivers makes it more difficult to get this summation correct.
Hi. Would you say that for a particular combination of driver sizes place on a baffle of a certain size, there are going to be 'no surprises' whoever is doing the designing? i.e. if you have a 6" woofer and a standard 1" tweeter on a baffle 8" wide, there's only so much difference in polar response you can achieve, whether it's $10 drivers, or $1000 drivers?
This is basically a rehash of the idea that only the frequency response matters and the price and cone materials and other specifications don't matter. I disagree.
I wasn't really talking about waveguides and horns, just about generic direct radiator speakers that feature the same driver configuration as each other.I disagree. The design of the enclosure can make a difference, and not just because of its size. For example the waveguide used (if any), edge diffraction. An LSR305 is just boring drivers in a rectangular plastic box - I suspect it's the waveguide that makes it measure so well.
It's art and scienceAnd if it really is science and engineering, why do you need a designer at all?
One can dream...And if it really is science and engineering, why do you need a designer at all? You really could just program the known objective characteristics of the drivers and box into a computer (because the designers are doing it with science and engineering, right? Not intuition, feelings, guesswork) and model the result. And you could set the computer off finding the optimal arrangement of drivers, box, waveguides, crossovers that would give the designer the 'best' result. Then order the bits and glue it all together.
But on this topic, and the notion of "well-engineered", I see a paradox (or whatever the right word would be). We are led to believe that designers are using science and engineering to achieve miraculously different measurable results compared to the next designer (or why bother?), but aren't they all using the same science and engineering?
If this isn't possible for some reason, then I call the bluff of the designers: they're still relying on convention, fashion, guesswork and intuition, not 'science'.
And if it really is science and engineering, why do you need a designer at all? You really could just program the known objective characteristics of the drivers and box into a computer (because the designers are doing it with science and engineering, right? Not intuition, feelings, guesswork) and model the result. And you could set the computer off finding the optimal arrangement of drivers, box, waveguides, crossovers that would give the designer the 'best' result. Then order the bits and glue it all together.
No designer designs a speaker without extensive listening which proves my point that it's all unknown. Frequency response is not the final arbiter all it does is tell you how bright or low different frequencies are. Which is just matter of preference anyway.
Frequency response is not the final arbiter all it does is tell you how bright or low different frequencies are.
A good way of putting it!As it is now this field is closer to some vague pseudo-artistic woodwork fetishism that's somehow related to sound rather than something with clear goals about what speakers are supposed to do.
While I try to minimize visible diffraction ripples in the frequency response for good measure, I have no evidence that even strong diffraction effects have significant audible consequences...
So while 'designers' are fetishising the latest high tech woofer that can work up to 5 kHz or whatever, and using their golden ears to tune their first order crossovers with it - generally being 'artists' - they could simply have added a low cost third 'way' using DSP and solved all their problems at a stroke. And it could have been a more-or-less automatic process that required very little in the way of artistry.
DSP can't fix everything. In particular, it can't fix directivity (so, for example, you can't tell it to fix something in your off-axis response without altering the on-axis response too, at least not in the general case). It also can't make your speaker play louder (quite the opposite, in fact). These kinds of acoustic problems still have to be solved the old-fashion way, by playing with various transducers, materials, enclosure shapes, etc.
I didn't say it did. I said that it allows you easily and transparently* to add another 'way' to bridge the yawning chasm between your 8" woofer and 1" tweeter. And that will certainly allow it to play louder.DSP can't fix everything. In particular, it can't fix directivity
Yes, but together with the on-axis anechoic response graph. One without the other won't tell you at what angle the response is flat, if it ever is, of course.Is it possible to tell, from a polar graph, how much one should toe the speakers in?
Is it possible to tell, from a polar graph, how much one should toe the speakers in?
Many modern 'speakers have a response that rises at HF. This is both because they stand out on dealer demos (listen to all that detail) and because many people prefer to have the 'speakers pointing straight on rather than angled, for aesthetic (WAF) reasons. If that's the case, then to achieve a flat response at the listening position they need to be toed in, by an amount that can be seen from the polar diagram and anechoic on axis response.Most speakers are designed so that the best possible response is obtained directly on-axis. So the answer is simple: the speaker should be facing the listener.
If there are multiple listening positions, then yes, I guess off-axis response could be used to inform the choice of angle. In fact, GedLee has a paper describing exactly that.