Axiom Home Page Forums General Discussion Home Theater Tweeter in Axiom speakers M5HP

Chiru, these are the changes:

Tweeter - compared to v3 and earlier

I'll start with saying the v2 tweeter that was in my old Axiom gear distorted at louder listening levels. The old tweeter had a plastic faceplate. The new tweeter has a die cast aluminum faceplate. This improves cooling and makes the whole assembly more rigid. The rear chamber of the tweeter is larger. This lowers the resonant frequency of the tweeter to below the crossover region which leads to a smoother amplitude response. The new tweeter also incorporates a shallow horn design that results in smoother off-axis response at higher frequencies (likely above 10KHz). The new tweeter is also able to handle more power and has a much heavier magnet and over-all build that makes it heavier than some mid-range and woofer drivers. The protective cover on the tweeter has been changed from a lens to a grill and I think that has also made improvements in the smoothness of the amplitude response particularly off-axis. I am also quite sure the driver itself is thicker leading to less break-up at higher volumes.

The end result is absolutely no distortion that I can hear and wide off-axis response leading to ethereal highs. From what I can hear, there are no improvements needed.

High power woofer

The HP woofer has a 1.5" voice coil rather than the standard woofer's 1" diameter. The basket is cast rather than stamped. The surround is thicker. The magnetic circuit is beefier. The HP woofer weighs more than the 12" driver in my Sony subwoofer even though it is only 6.5" in diameter. Given all the changes, it provides greater peak-to-peak excursion.

The end result is it can achieve higher sound pressures with far less distortion than the standard woofer. It doesn't really go lower than the standard woofer. It goes as low but more cleanly.

Cabinets

The cabinets are better braced and better stuffed. Someone characterized and did some modeling to figure out where to brace and how much to stuff. I also think the type of MDF changed but I can't say that for sure. Of course now the wood veneer is standard.

Packaging

Some R&D went into the foam and boxes too.

Cross-overs

The component selection, placement on the board and routing of traces are better engineered.

Finally, the bottom line is the Family of Curves and how they sound. None of the above matters if the curves are bad and they don't sound better than the old versions. Axiom has upped their game by taking more curves around the speaker, improving their interpretation of what the curves are telling them and understanding how peaks, valleys and ripples in the curves inform improvements in the design.

I think they nailed their understanding of all of this. How do I know? Because no matter what Axiom speaker I listen to, they have similar characteristics in fidelity, sound stage, imaging and acoustic disappearance. As you move up in the speaker lines, they can achieve lower lows, higher sound pressures, wider and deeper presentation and more pin-point imaging.

They figured out the one formula to rule over all their speakers. Speaking as an electrical engineer, I consider this to be the embodiment of enviable engineering.

It only took 40 years and nearly killed Ian in the process.