Aurum Cantus Tweeters

[mrspis]

Witch tweeter is better?
Aurum Cantus AST30130 Aero Striction Tweeter 276-444
Aurum Cantus G1 Ribbon Tweeter 276-420
I see that Aurum Cantus AST30130 Aero Striction Tweeter is more expensive, and has better low end extension, but its not made of ribbon? That's what confuses me..

this is what i found
"However, after many decades (and countless product failures), we have learned that conventional long flat ribbons are to be avoided (even if they look impressive).
Instead use many tiny collocated ribbons, working in unison.Some describe them as sandwich, bellows, folded or accordion ribbons."
So, if i understand correctly, Aero Striction Tweeter is superior to normal ribbon tweeter?

[mrspis]

I like that the AST tweeter has crossing as low as 1.000hz, that's what i like the most about it! But i don't really know the difference between the classical ribbon tweeters (G1) and AST tweeters (AST30130)?

I also see that Aurum Cantus uses the AST in their best and most expensive speakers (NEW GRAND SUPREME, original GRAND SUPREME uses G1) so i assume that it is their top of the line tweeter?

I see by the picture comparison that AST is much wider than g1, so i assume that's why it has a much lower Recommended minimum crossover frequency: 1,000 Hz, in comparison to g1 which has Recommended minimum crossover frequency: 2,000 Hz, and that's what i really like about AST over the G1, it can be used as a partial midrange, with the right crossover.

AST http://img705.imageshack.us/img705/7...upreme2530.jpg
G1 http://img208.imageshack.us/img208/7055/supremeo.jpg

What i don't understand is how NEW GRAND SUPREME can have Frequency Response 25Hz-40kHz when AST goes only to 22khz? That's whats bugging me over the G1, the G1 has freq response that goes as high as 40khz, so it can be used even as a super tweeter.

cheers

[gornir]

Hi mrspis,

Originally Posted by mrspis

I like that the AST tweeter has crossing as low as 1.000hz, that's what i like the most about it! But i don't really know the difference between the classical ribbon tweeters (G1) and AST tweeters (AST30130)?

With a quick look at it, the AST looks like a variant of a an AMT tweeter (Air Motion Transformer) as e.g. http://www.hs-devices.com/index.htm

However, I would be cautious to trust the distortion plots in the Aurum Cantus spec sheets. They don’t tell at which level they are measured. Almost all their ribbons look very low distorting on paper, even down below 1kHz which makes me suspicious. In fact, almost too good to be true.

The AST30130 has a nasty dip at 4.5kHz, most likely because of some sort of diffraction issues. It’s hard to know why without looking at some off-axis frequency measurements. It has a bit of a “roller coaster” frequency response. Perhaps not the easiest tweeter to work with compared to other ribbons.

Originally Posted by mrspis

I also see that Aurum Cantus uses the AST in their best and most expensive speakers (NEW GRAND SUPREME, original GRAND SUPREME uses G1) so i assume that it is their top of the line tweeter?

Yes, but does it sound better? Surely they will sound different, but better is up to personal taste as always. The “New Grand Supreme” seems to have a lot more complicated cross-over design than the old one. They use a 4-way cross-over (150Hz, 210Hz,1.8kHz) with a rear firing tweeter crossed at 12kHz. Could the rear firing tweeter be to mask the AST;s shortcomings? I don’t know, but it raises my eyebrows considering its published frequency measurements.

The “Old Grand Supreme” has a straight forward 3-way cross-over (110Hz and 2200Hz) with the G1 ribbon crossed pretty low.

Originally Posted by mrspis

I see by the picture comparison that AST is much wider than g1, so i assume that's why it has a much lower Recommended minimum crossover frequency: 1,000 Hz, in comparison to g1 which has Recommended minimum crossover frequency: 2,000 Hz, and that's what i really like about AST over the G1, it can be used as a partial midrange, with the right crossover.

In the “New Grand Supreme” they cross the AST at 1.8kHz. I would say it’s hard to say if a 1000Hz cross-over would work without any independent measurements available. My guess is that it doesn’t work considering e.g. distortion etc.

Originally Posted by mrspis

What i don't understand is how NEW GRAND SUPREME can have Frequency Response 25Hz-40kHz when AST goes only to 22khz? That's whats bugging me over the G1, the G1 has freq response that goes as high as 40khz, so it can be used even as a super tweeter.

Don’t believe the manufacturers sales brochures, they are mostly bogus.

Go for the Mundorf “Holographic Sound Devices” AMT tweeters instead of the Aurum Cantus AST or the G1 or some other High quality ribbon like The RAAL or Fountek Neo Pro 5i, if you ask me.

But I don’t think any of these would do “1000Hz”, though.

/Regards

/Goran

[mrspis]

So you would say that the G1 would be a better buy?

[gornir]

Originally Posted by mrspis

So you would say that the G1 would be a better buy?

I'm afraid that’s impossible to say since I haven’t tested or listened to either of them. The G1 seems by the specs to be a bit easier to work with, but the decision is yours.

Buy them both, test and listen to them and sell the one you don’t like or visit an Aurum Cantus loudspeaker dealer and listen to them and see if you like them in their application.

I’m sorry, but that’s the best advice I can give with the given circumstances.

Have a nice weekend.

/Goran

[Paul W]

This thread includes a few 30130 measurements...

An information roundup for larger AMTs - AVS Forum

[gornir]

Originally Posted by Paul W

This thread includes a few 30130 measurements...

An information roundup for larger AMTs - AVS Forum

That looks a bit better.

However, it doesn’t tell if the downwards slope against lower frequencies is caused by a protection cap and thereby filtered and the frequency is shown in a 90db scale from 10-20000Hz which masks the irregularities higher up in frequencies. The distortion is between 0.1-0,3% and at the highest at 1.5kHz, but it doesn’t say at which level its measured.

/Goran

[mrspis]

I see that New Grand Supreme has a rear firing tweeter? Why? I don't understand its purpose..