Aurum Cantus or Raven?

[planet10]

It seems the Heils are not that efficient. How do you deal with the difference of them being 4 ohms and only 93 db? I'd imagine the Corals are much more efficient.

We measured the Heils at over 100 dB (and the padding needed to match them to the push-push pair of 92 dB Fostex confirms that....

Old ones seem fine, but when you can buy a new pair for the same kinda price (AMT had some up on eBay for $300/pr)... it will be interesting to see what one1speed gets in reply.

dave

PS: excuse the Excel charts (Excel is just so clunky)

 

[planet10]

and here are pics of the Heil/Fostex i was referring to.

 

[planet10]

and an earlier set of 3-way (eminance mid, and original alnico AMT woof/PR)

 

[one1speed]

Dave

Thanks for the picts. I did hear back from Heil and they are saying $300 plus shipping/taxes for a pair. Not bad. Expecially considering the quality everyone speaks of. My only issue is that if I go in that direction, I need to find a way to mount them on an open baffle. Any thoughts?

Layne

 

[planet10]

I need to find a way to mount them on an open baffle. Any thoughts?

A hole with a "shelf"?

dave

 

[one1speed]

i had thought of that as well. have to admit, i don't love the idea. it seems from most of the mountings i've seen, including your picts, the front of the tweeter box is sitting in line with the driver/baffle. this would actually put the ribbon portion of the tweeter behind the baffle, which i'm guessing is not a good thing. i had wanted to mount the tweeter below the full ranger. i could sit it on the bass box, but it still would sit back too far i'd think.

maybe a small shelf could be built above the full ranger? but then i'd want it to sit close to the full ranger. i'm not sure this can work for this. would be tough to get it to work i'd think...

 

[BTW]

One more question, if you don't mind. It seems the Heils are not that efficient. How do you deal with the difference of them being 4 ohms and only 93 db? I'd imagine the Corals are much more efficient.

Thanks!

The AMTs by itself is 100 dB so , the Corals are at 95 dB and I actually need to use an L pad on the AMTs as they are more efficient than the Corals.

 

[planet10]

this would actually put the ribbon portion of the tweeter behind the baffle

However it is mounted. i think i'd try getting the central part of the ribbon flush with the baffle.

dave

 

[ralphs99]

You could also consider the Eton ER4 which is a similar technology to the Heils, I believe.
I'm always a bit wary of putting down my hard earned for something that doesn't come well documented. In that respect the AC G2Si has been thoroughly tested. Check out:

http://206.13.113.199/ncdiyaudio/mark/G2si/arum_cantus_g2si_test_results.htm

I'm in the middle of a new design at the moment. As part of the project I am trying out an Eton ER4 and will also be evaluating an AC 2Gsi and Raven R2 when they finally arrive.

My inital impressions of the ER4 are mostly positive. Smooth & detailed. Low efficiency, hard to mount and a rising response that needs some EQ. I'm currently struggling with it's dipole nature and the effect that has on the power response. More work is needed here.

I can send some FR plots of the ER4 if you're keen.

Cheers,
Ralph

 

[Illusus]

The Eton AMT's price is double of the Heil and looks considerably less impressive, if that means anything. The Eton's efficiency is pretty low at 88db, not really what Speed is looking for.There's also the Mundorf AMT but its price is even higher (~$400 for a 2340) and efficiency only marginally better at 90db for the lower priced models; 104db for the rest; HF extension is lacking when compared to most super tweeters.
I'd take the Heil over other AMTs due to it's proven, well documented and impressive performance. My view may be coloured by a few years of lusting after a pair, now that I know they're still available at a relatively low price I'll be buying a pair in the near future, I'm not bound by the mounting issue that Layne is...anyone want to trade for a hardly used pair of OEM G3's ?

 

[Illusus]

To mount the heils the shelf could be nothing more than a couple dowels. Felt or a diffusive profile(or both) could be placed on the bottom of any flat surfaces (top if the Heil is under the Fostex). One could also fashion some type of clamping mechanism to hold the driver in place.
I'd draw something up but I'm in the middle of moving and shouldn't even be thinking about anything else.

 

[one1speed]

Thanks to Illusus and everyone for the thoughts. I was unable to actually cut wood this weekend, as it rained most of the time. So, I have a little time to come up with some sort of sketch/thought to see if I can get the Heil to work out. Thanks to all! Any further thoughts are always appreciated.

Cheers!

 

[d'yermak'er]

ESS amt

Hi all,

I'm entering this thread alittle late , but would just like to say few things.

I've been an audio enthusiest for over 25 years and still haven't come across anything else like these. they're uique even by todays standards. I'm on my third pair, the new AMT 1Ds which I've owned for about 4 years.
New, they come horribly out of tune. Cabinets are crap,not braced, passive radiaters have no mass and I can go on.

I've since modded the hell out them and they are awesome!

I can get more indepth if anyone is interested.

These are the only other speakers good enough yhat can do tag team with my big VMPS RM40s. In many ways, the ESSs are better.

Planet 10, both your prodjects seem very cunning and refined. On the Fostex version, is that a passive in the back?

Thanks,Stan

 

[planet10]

Re: ESS amt

On the Fostex version, is that a passive in the back?

No it is a 2nd woofer. We really like the benefits of push-push loading...

dave