Tweeter type and brightness


I presently own Martin Logan Odysseys that I purchased new in 2005. I've enjoyed them very much but I'm having to replace the power supply board in one of them as I did in the other one about 5 yrs ago and I'm thinking that it may be time to look into speakers using more recent technology.

I auditioned several new sets at Sound Advice including the Monitor Audio silver 2, 6, 8 and 10 plus a small pair of ML's. I thought all of them were very good. Additionally, I bought a pair of Jamo Concert Eights several months ago that were fantastic for my type music which is mostly solo guitar. I regret selling them but at least I learned how good quality bookshelf speakers can be.

Anyway, I've read in several posts that metal dome tweeters have a tendency toward exaggerated or tinny brightness which can be very uncomfortable for me because of a hearing issue that I have. I want to avoid this and am asking for advice regarding this experience of others and what tweeter construction, if any, is generally best to avoid what I call screechiness.

I've been told that the technologies that best avoid this are ribbon tweeters or domes of some softer material than the various metals used in many of them. In one of the forums here on Audiogon this subject was discussed in some detail and at least several participants seemed to minimize the relationship between tweeter design and this problem. They suggested that more likely potential causes would be such things as room acoustics, interconnect quality, rake, crossover problems, etc.

I agree that each of these considerations could lend to the issue but I'm looking for a good starting point to at least minimize the contribution of the speaker design to this problem.

I've heard the gold series Monitor Audio speakers which do incorporate ribbons and they seem to work perfectly with my music but they, like the larger new ESL's are substantially outside my current budget limits. I'm currently using some borrowed temporary speakers while I'm waiting for the new circuit board so I can sell my Odysseys. In the meantime I would appreciate any advice I could use to help with an approach to selecting a speaker best suited to my needs. My upstream equipment includes Shanling solid state CD player, CAL DAC and Rogue Audio Sphinx 100W hybrid amp.
128x128broadstone
The better(more resolving) your tweeters and cables are; the more they will reveal shortcomings upstream(elsewhere in the system and recordings).
I've always gravitated toward silk dome but even some of those can be bright. I hate to say it but you usually get what you pay for.
There are many factors that can make a metal/soft dome tweeter sound harsh and the most common are the series cap used in the crossover to the tweeter, the internal wiring along with magnet composition and the internal vibration modulation of the crossover if implemented in a perfunctory manner.

I have the unique ability to swap out magnets on my dome tweeter drivers in a matter of minutes. These tweeters are the latest aluminum/magnesium composition and the difference between ceramic and AlNiCo is certainly NOT subtle with the ceramic sounding harsh, forward, shouty and somewhat confused compared to the AlNiCo magnets which sound smooth and natural with an expanded dynamic range and frequency range along with an improved top to bottom coherency.

At first the AlNiCo magnets sound dull but with further listening the whole sound field is solidified with real high frequency energy being reproduced with full weight, linearity and soundstage depth.

I wish I had the ability to swap in Neodymium magnets to asses their attributes but at this time that is not an option. Bottom line is to ensure you have the most high quality series cap in the tweeter feed and ensure the internal crossover is not being modulated by the internal vibrations of the woofer, an external crossover would be ideal.
Somehow I don't think magnet type has anything to do with frequency reproduction, and I agree that it can be painful to stick cables in your ears.
Many metal tweeters are harsh and bright...one particular major speaker manufacturer has been an example for years.

But, some metal tweeters have their resonances very well controlled, the Revel Salons being a great example: smooth, sweet, low distortion, non-irritating highs. Go for a low distortion speaker like that.