After looking at many designs it has become apparent that many favor 'cheaper' tweeters then the mid, or mid bass. This is seems backwards since the tweeter covers most of the spectrum (~4k to 20k).
Here is just a few of many examples
--> SEAS 5INCH or
--> http://www.troelsgravesen.dk/W12.htm or
--> http://www.troelsgravesen.dk/W15.htm
In car audio, usually the cheaper tweeters are awful sounding. So why not use higher range tweeters?
Here is just a few of many examples
--> SEAS 5INCH or
--> http://www.troelsgravesen.dk/W12.htm or
--> http://www.troelsgravesen.dk/W15.htm
In car audio, usually the cheaper tweeters are awful sounding. So why not use higher range tweeters?
And a lot of cheap tweeters perform quite well.
I look for two things in a tweeter: smooth top end, and clean low distortion sound when swept down towards resonance. The first you will see in published response curves. The second you can easily hear by ear.
After those two items, much of the sound of a tweeter is down to the mounting of it. If you flush it in smoothly to a cabinet with clean edges and no reflective surfaces, then a cheap tweeter can sound quite good.
More tweeters have their performance messed up by bad mounting than bad design.
David S.
I look for two things in a tweeter: smooth top end, and clean low distortion sound when swept down towards resonance. The first you will see in published response curves. The second you can easily hear by ear.
After those two items, much of the sound of a tweeter is down to the mounting of it. If you flush it in smoothly to a cabinet with clean edges and no reflective surfaces, then a cheap tweeter can sound quite good.
More tweeters have their performance messed up by bad mounting than bad design.
David S.
This premise is incorrect. When we talk of frequency range, because of how we hear, we need to talk in octaves, a logarithmic scale.
4-20k is just over 2 octaves, leaving just under 8 octaves (20-4k) left to cover, althou in most cases even 7 octaves (40-4k) would be a good goal for a 2-way.
If one considers the typical distribution of energy in the music, 300 Hz is about the 1/2 way point, and a very suitable place to XO.
dave
Part of it is down to how you use them.
In a typical passive design the loudspeaker designer will cross the tweeter over at around 2.5-3khz. Plenty of more affordable tweeters cope with that well enough, even if they can be bettered.
With some of the more exotic designs like the Linkwitz Orion the designer has gone for a low crossover point. This requires a really well behaved tweeter, the majority of tweeters that can cope with this are pretty expensive.
It is the law of diminishing returns in many cases. The benefits of expensive tweeters against the best mid price or even budget designs are relatively small.
Music lives in the midrange but you shouldn't mess that up with harsh lower treble.
In a typical passive design the loudspeaker designer will cross the tweeter over at around 2.5-3khz. Plenty of more affordable tweeters cope with that well enough, even if they can be bettered.
With some of the more exotic designs like the Linkwitz Orion the designer has gone for a low crossover point. This requires a really well behaved tweeter, the majority of tweeters that can cope with this are pretty expensive.
It is the law of diminishing returns in many cases. The benefits of expensive tweeters against the best mid price or even budget designs are relatively small.
Music lives in the midrange but you shouldn't mess that up with harsh lower treble.
I think alot of it also comes down to dispersion in the top octaves as well. The D26NC is the shockingly best tweeter I have ever measured on axis taken as a whole (distortion and response flatness) but it had a very limited dispersion in the top end, and to me sounds a bit overly "dead".
I've fallen in love with the B&G Neo 3 PDR lately, I suppose on the grand scheme of things it's not especially expensive.
There are some exceptional tweeters, like the Heil AMT that are worth every cent of their chunky price tag, but I've found that most of the tweeters I like are in the 60-80 dollar range.
There are some exceptional tweeters, like the Heil AMT that are worth every cent of their chunky price tag, but I've found that most of the tweeters I like are in the 60-80 dollar range.
IMO it is the defacto standard 1" dome tweeter that is the limiting factor in most loudspeakers. While it may only cover a "few" octaves, these are the critical octaves in that this is where nature has made our hearing most accute. It turns out that getting beyond the "1" tweeter standard " moves the design into a whole new realm that gets complex and expensive. So quite simply the "standard" is inexpensive, easy to use and "acceptable" for most. But it is, as I said, the factor that limits performance. Every 1" dome speaker that I listen to has that same "something is missing" or "TOOOO much!" sound quality.
But I agree with Dave, mounting is usually done wrong and makes a big difference.
But I agree with Dave, mounting is usually done wrong and makes a big difference.
Earl does that apply ( in your opinion of course) to all domes ? Even the 10mm and 32mm??
What do we use in place then lightweight cones?
Ribbons??
I have always thought
that the old Foster 50mm paper cone with the large damped chamber had a good sound and reasonable dispersion and the only ribbon I have used is a cheap Foster which was pretty tinny and only good as a super tweeter
What do we use in place then lightweight cones?
Ribbons??
I have always thought
that the old Foster 50mm paper cone with the large damped chamber had a good sound and reasonable dispersion and the only ribbon I have used is a cheap Foster which was pretty tinny and only good as a super tweeter
What would be wrong mounting to far away from the mid or on a to big flat surface?
I think that 1"dome's are improving when they are designed to have bigger xmax, so the distorsion at Fs will be lower.
And as I look at specs I usually see that a 28mm is easier to cross ten the smaller 1" ones, so that is the better size or a 1"with more room to extrude.
You get the most bang for the buck with cheap 3/8" poly domes based on the Audax design. They cost practically nothing. More expensive tweeters that are better do not give improvement proportional to the added cost. The money is better spent elsewhere. This tweeter's performance can be improved by crossing them over at fairly high frequencies and using them in arrays. That may not sit well with those for whom imaging is their primary concern...or with people who manufacture more expensive tweeters. In arrays each tweeter normally sees only a fraction of a watt yet an array of half a dozen can have a capacity of well over 100 watts, even nearly 200 watts. Compression is negligable and directivity can be controlled by whatever physical arrangement you design.
In my earlier days I had a thing for paper twin-cones in my car. It got me a few funny looks, and I didn't understand then why I was 'different'.
Apart from the fundamental issues with dome tweeters, I think car tweeters (in two way co-axials) often suffered from resonance being accentuated by the cap, and from some kind of gross distortion/breakup/surround termination issues.
I think that any reasonable two way split system with an appropriate crossover should perform as well as could be expected from that configuration.
Its the technology that has too many limits.
Lets say that we want a device that can go down to 1000 Hz or below because a crossover above that point - where our ears are very accute - is not a good idea. And lets say that we want high efficiency for good dynamics and high power handling for good headroom and MAX-SPL. Well NO 1" dome is going to do that, the voice coil is too small. grow the voice coil and you get some of the things that you need, but others - like directivity - get worse. So as the device gets larger you have no choice but to use some form of waveguide - improves efficiency, directivity and the ability to use a much larger voice coil improves dynamics and power handling. But waveguides are not trivial to design and use and boost the costs substantially, which is back to the point that I first made - dome tweeters are cheap and easy.
Ribbons has some pluses, but the low efficiency and lack of directivity control are major issues.
Too far away is an issue, but the area arround the tweeter is also critical. It must be clean and diffraction free.
As I said a ribbon has very low efficiency and thats an issue. A compression drivers is basically a dome tweeter that has gotten large enough that it needs something done acoustically to help its performance. A waveguide not only entends the usable bandwidth of this larger dome, controls the sound radiation in a way that a freely radiating dome cannot, and enhances the efficiency especially at the critical low end, thus allowing for much lower crossover points. Downside is that poorly designed horns ruin the whole concept. Unless you have a very well designed waveguide (and matching crossover) all the advantages are lost in the poor sound quality that results from the horn.
A horn loaded ribbon could be made to work effectively, I just have never seen one.
I'm a bit confused by your statement that ribbon tweeters have low efficiency. I have been listening to Raven tweeters that are listed as 98 dB , 2.83 volts at 1 meter. To match them to a pair of PHL 6.5" drivers they are padded down quite a bit. Also, here is a Fountek ribbon horn loaded with a 95.5 db efficiency. In comparison to dome tweeters this is quite efficient.
Fountek NeoCd3.5H Horn Tweeter: Madisound Speaker Store
I realize horn loading is kind of you thing, but I feel like I am missing something. Could you explain? Thanks.
Fountek NeoCd3.5H Horn Tweeter: Madisound Speaker Store
I realize horn loading is kind of you thing, but I feel like I am missing something. Could you explain? Thanks.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.