Good afternoon Gedlee,
They do look like great systems. You've given me lots to think about! I am more interested than ever to dive into a prosound project. The dynamics are attractive, as that is something I have always found lacking in the few systems I have cobbled together. The waveguides you use are particularly interesting - the material you use to 'fill' the waveguides - does this reduce unwanted reflections or help dispersion? I understand if this is a trade secret that you do not wish to comment on.
I'm not as sure of that point - perhaps I've misunderstood? Do you mean in terms of comparing drivers with similar application goals? If not, I would argue that application goals that differ lead to drivers that have different specialties.
For example, consider these two drivers:
The Peerless 830884 8"
The Eminence Beta 8A 8"
Here we have an example of two drivers that could be considered good, but have different goals. The Peerless would not be the best choice for high SPL applications, and it looks as thought it would have to cross over lower comparatively. It does however appear to have smoother response through its usable band (though the resolution of the provided data is not great!) and a bit more low end extension. In my opinion the Peerless would be the better choice for a modest SPL, comparatively near-field application, where the Eminence driver would be my choice for higher SPL, and higher dynamic situations such as large room live-performance oriented system or high quality home theater.
Certainly a random comparison of two drivers at face value is not to be taken as proof that prosound drivers aren't for use in hi-fi. That's not what I mean at all and I bet the systems you've put together with prosound units have great SQ and the rest. But my (rather long-winded!) point is that I am not certain even great prosound drivers are the best fit for every requirement.
Thank you! I do try, though I must admit that my preconceptions get the best of me at times.
Jim
They do look like great systems. You've given me lots to think about! I am more interested than ever to dive into a prosound project. The dynamics are attractive, as that is something I have always found lacking in the few systems I have cobbled together. The waveguides you use are particularly interesting - the material you use to 'fill' the waveguides - does this reduce unwanted reflections or help dispersion? I understand if this is a trade secret that you do not wish to comment on.
I'm not as sure of that point - perhaps I've misunderstood? Do you mean in terms of comparing drivers with similar application goals? If not, I would argue that application goals that differ lead to drivers that have different specialties.
For example, consider these two drivers:
The Peerless 830884 8"
The Eminence Beta 8A 8"
Here we have an example of two drivers that could be considered good, but have different goals. The Peerless would not be the best choice for high SPL applications, and it looks as thought it would have to cross over lower comparatively. It does however appear to have smoother response through its usable band (though the resolution of the provided data is not great!) and a bit more low end extension. In my opinion the Peerless would be the better choice for a modest SPL, comparatively near-field application, where the Eminence driver would be my choice for higher SPL, and higher dynamic situations such as large room live-performance oriented system or high quality home theater.
Certainly a random comparison of two drivers at face value is not to be taken as proof that prosound drivers aren't for use in hi-fi. That's not what I mean at all and I bet the systems you've put together with prosound units have great SQ and the rest. But my (rather long-winded!) point is that I am not certain even great prosound drivers are the best fit for every requirement.
Thank you! I do try, though I must admit that my preconceptions get the best of me at times.
Jim
It would be very interesting to hear the Peerless and the Eminence compared in the same 3-way rig. Certainly a worthy experiment.
I have heard the Beta-8 used as a midrange with only a small inductor to flatten it. A really nice driver. Much more "refined" than you might think. Wonder how the Peerless would compare. Less efficient, but other than that?
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I have heard the Beta-8 used as a midrange with only a small inductor to flatten it. A really nice driver. Much more "refined" than you might think. Wonder how the Peerless would compare. Less efficient, but other than that?
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i don't consider compression drivers to be of acceptable sound quality beyond about 10 khz. ( this doesn't include ring radiators / bullets or custom drivers like the supertweeter in JBL Everest ).
but then i also don't consider dynamic headphones to have acceptable treble sound quality.
and when i heard electrostats they didn't have acceptable treble sound quality to me either.
hm ... and i only hear to 17 khz. i wonder what guys who hear to 22 khz think LOL.
if i can hear the difference between 1" alu/mag dome and 1" titanium dome then i certainly don't want to be listening to 1.75" metal dome ...
i would gladly take a compression driver with 1 inch VC, 1/3 inch throat and a 5 slit phase lens. but who will give one to me ? 🙂 i can't afford JBL Everest 🙂
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I agree with Borat, 1.75" metal dome just can't sound good, it has distinct metalic resonance. Although a piece of foam, like in gedlee's system, should absorb most of the resonance. The only compression driver I'd get is BMS, because it has extremely well damped ring diaphragm.
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With you on that Mike, and my whole affair with horns and HE in general started with the JBL 075/2402 annular ring radiator horn tweeter. I've had both alnico and ferrite. Currently using the 2402 ferrite version. It's not perfect, but there is something about it that I find rather appealing.
And I don't consider anything above 10 kHz to be of much importance. Numerous tests on this have been done and in general you can remove everything above 10 kHz and almost no one will detect it. It's possible to design a test and a signal for which this is not true, but on music sources with typical listeners no one can tell. No matter what you might think, the frequencies above 10 kHz just are not that important.
The ring diaphragm is no better damped than a dome. Its just smaller and therefor lighter.
Oh No! You'll lose a whole octave!!
I actually like stuff that is rolled off about 12-15K. Systems that go higher sound fake to me. Too sizzly. I just don't hear that stuff in real life. But everyone's ears are different.
Yeah Kevin, we are on the same page. The horn stuff isn't perfect, but done right it has a realism that few other drivers can approach.
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A good question!
I just don't find that much difference. I hear/feel most of that impact down lower. Rock kick drum does have a lot of HF energy, at least mixed live, but it it doesn't go above 10K, IIRC.
Getting the crossover phase and horn position right has a lot more effect on the impact. For me, at least.
I just don't find that much difference. I hear/feel most of that impact down lower. Rock kick drum does have a lot of HF energy, at least mixed live, but it it doesn't go above 10K, IIRC.
Getting the crossover phase and horn position right has a lot more effect on the impact. For me, at least.
Nothing audible.
What most people don't realize is that there is very little above 10 kHz in our natural world. Air absorption increases quite dramatically above this frequency and so the sound content for any instrument, or otherwise, is seriuosly affected. And necessarily our hearing never developed to hear sounds that aren't there.
When you are in a large hall listening to an orchestra there is nothing above 10 kHz, it's all absorbed on its way to you. When you go to a live concert they boost this way up so that they can measure it and claim that it's there, but that's about it. In a hearing test nothing above 8 kHz is ever tested and from intelligabilty tests it is know that nothing above 8 kHz adds or subtracts from intelligability. The only people who care are the marketing guys.
Not sure I agree with you there, Earl. A lot of Hi-fi end users care. If it doesn't have the top end sparkle, it's not hi-fi. Is that fed by the marketing, or vice-versa?
So we tend to over use it, just to prove we have it. I sure agree with you there. (surround sound suffers a similar fate)
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So we tend to over use it, just to prove we have it. I sure agree with you there. (surround sound suffers a similar fate)
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Again, no one complains about my speakers NOT having enough hi-end, if anything they tend to sound bright because of the unusually wide coverage at 10 kHz. But these speakers don't shine at 20 kHz and I really don't care. It's all about "perception". I deal in "quantifiable auditory perception" and most people deal in "marketng perception". The two things tend to be quite different.
I can still hear to 15khz or so, and HF phase differences are also audible to me so I don't know that a response to 10khz would fully employ my critical listening facilities.
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how can it be? ring has inner and outer edges damped, while dome has only one outer edge damped.
Earl, is there a reason you've chosen driver with polyimide dome instead of titanium for your speakers?
That you can detect a 15 kHz tone is not relavent, its the signal that doesn't contain anthing this high up - unless its added synthetically - and detecting is also not sound quality. As to phase being audible at these frequencies that absurd.
Unless you under 20 Yrs old, and you have super human hearing, your hearing will be down by 10 dB or more at 15 kHz. If you are a typical middle aged adult, it will be down by about 20-30 dB. If you are over 40 or so, its gone.
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Thats a good point, but the surround is not a major form of damping, but there is some and yes it will be greater for the double surround situation. But the main reason for the ring is the lighter diaphragm and more HF response while allowing for a larger VC.
The metal diaphragms break-up more at VHF, and they cost a lot more. The metal diaphragms are more reliable thats true, but reliability in a home system is not a big issue. I have tried and like the DE500, but its nearly twice as expensive and its not that much different.
That's good to know. I hear so many that sound unnaturally sizzly to me. Forced hi-end
But that may be 10K or under, not sure. Stuff up that hi is so hard to identify. It's more like you sense it than feel it. For most of us old farts, anyway.
I'm quite happy with the old range of 30-15Khz.
Just sort out the HF distortions, that's what make a system sound bright or "sizzly". Undistorted flat FR to 20kHz or more certainly doesn't make a system sound bright but will surely add to SQ.
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