Ring radiator tweeters - the future?

Why no tweeter?

Read the paragraph "The Quest for that Old-time Religion".

There was a time, two generations ago, when the full-range cone driver reigned supreme. In an age when the radio console together with the shellac 78-rpm record defined audio quality, a frequency range of 60 Hz to 9 kHz was about as wide a window as was needed or desired for the enjoyable reproduction of available source material. If anyone dared to open the window any wider – especially in the treble - they ran the risk of exposing gremlins such as needle scratch and other high-frequency hash and noise. With the advent of the high-fidelity phenomenon in the 50s, the audio industry moved inexorably toward multi-way loudspeakers, such as two and three-way designs, as a means of expanding the bandwidth at the frequency extremes. The advertising campaigns/hype at the time were so effective, that for many people Hi Fi became synonymous with bandwidth. Many consumers expected to pay a premium for a high-fidelity loudspeaker basically because of its increased bandwidth. Even today, many audiophiles and audio engineers seem convinced that the road to hi-fi heaven lies at the frequency extremes. Of course, music lovers know that this is patently false, and that the emotional content and drama of live music have little to do with the frequency extremes.

Multi-ways effectively cut the music in half. Do you really think the speaker designer can put it back together again? Even 1st order is only in the small sweet spot.
People commonly ask, why is a speaker $10,000 for $200 worth of drivers. IMHO the price is for the expertise of the designer making the drivers work together. A very tricky task as the x-over can't just be designed on paper, from what I have read from the guys at madisound.com. You have to tweak it by ear over and over again to make it sound right.

As stereophile wrote on Krell Resolution 1 speaker:

I must assume that Mikey's thinking the Resolution 1 sounded a bit "rich" in the upper bass is due more to the woofers' restricted passband. (The more you limit a drive-unit in the frequency domain, the less well defined its output will be in the time domain.)

Running a driver full range with no high or low-pass x-over is the way to go or timing will be off.

The so called "tweeter" of the Magneplanar QR series, like my MG1.6QR, is not a physically separate driver, like the ribbon used in the MG3.6. It is just a section of the diaphram that has lighter conductors and can vibrate at higher frequency. In some ways it is like a full range cone driver, where breakup of the cone allows the area near the voice coil to vibrate at higher frequencies than the outer cone area. I actually prefer the Maggie QR over the ribbon, and the money left in my pocket is nice too.

Gmood1...The Fostex FF225 appears to be much flatter out to about 12KHz, where it drops off completely. At the low end there is a rolloff starting around 200 Hz, but it is smooth and gradual and easily handled by equalization down to where a SW would take over. This driver, which costs about 1/4 of the F200A, is a better fit to the requirements of my project.

Eldartford , looks like you've done your home work on this one. I wish you luck with the project. I know several Audiophiles that went OB. They all claimed never to return to a box speaker again. Thanks for the links Cdc.

Cdc, your comments are based in a rich misunderstanding of what it takes to make a good speaker. Fact is most single driver systems have worse timing errors than properly designed multi-element speakers.

Your history lesson also underestimates how much people love bass. For 99.999999999999999999% of the public anytime you get more bass....you get a bigger smile. Advertising had nothing to do with it.

Speaker designers are not obsessed with frequency extremes, the driver manufacturers are. In most cases better mid band performance leads to better bandwidth performance. Most good speaker design manufacturers are obsessed with either bass or midrange or simply obsessed.

Single driver speakers are not the answer, most are inferior for the very reasons you find flaws in multi-element designs. Exactly how difficult is it to perfect one driver to the point where it is demonstably superior to multi-way systems? You would think price advantages and limited R&D would make this style of speaker very popular. To build a Fostex in a box, you call madisound, cut some wood and you have a speaker. I'm not sure it requires any math?

BUT despite inherent market advantages, overcoming the obstacles seems to be very difficult, as this proven year after year. As single driver system remain only viable to fringy audiophile types who don't listen to powerful large scale or popular music.

A good example of the point I'm trying to make;

Cain & Cain Abby versus a Blue Sky System One? Both $1500, ones modern AM radio the others the real deal.

Guess where my money's going....with the ring radiator...

Best Regards