Has anyone used this puppy?

[LING GOWA]

h1571-08 u18rnx/p

[Jed]

I doubt it since it hasn't reached most distributors yet.

[Face]

I'd like to try a pair of those out.

[Jonasz]

It's already been deemed inferior to the ER18.

https://www.htguide.com/forum/showthread.php?t=35169&highlight=idunn

[chrismercurio]

Sonus Faber has a variant in their Liuto line...

[Jed]

It's already been deemed inferior to the ER18.

https://www.htguide.com/forum/showth...ighlight=idunn

In that thread I made the mistake of comparing the ER18 to the U16. The U18 appears to be a close cousin of the ER18- which means it should perform really well.

[Carl V]

Sonus Faber has a variant in their Liuto line...

well, what do you know.
I heard that driver this Fall
while I was in Italy. I
spied a hi-fi shop in Milan.
And I didn't want to do any shopping.

I listened to a nice 3-way in this line
It apparently had this 6 " poly/textile
midrange(mid-woofer) it also had a 9"
metal woofer (alu.mag) & 1" tweeter.

They were driving it with Chord &/or Einstein.

Initially they had them on the long wall, near the corners.
they moved them out away from the corners (but the guy
placed them equal distances about 3 ft from back & side wall)
and they sounded warm & a bit thick in the bass/lower midrange.
So, I suggested another foot in from the side wall.
AH! now it sounded better. Their owner liked wide placement.
But it didn't work in this room or with these speakers. The
salespeople (not owners), smiled & liked the new sound.
It was lively and fun sounding. Great detail & nice bass impact.
SOundstage was now wide & deep. Great imaging. Toe tapping.
Damn but a good 3-way can really sing. We had fun for about
a half an hour once we set 'em up "properly' imho. They seemed
to like it as well. It was entertaining having them spin discs
that they thought I might like & that might show off the Liuto.

Back to the sidewall & out came some Wilson Bensch ACT C60.
Very nice... a different sonic presentation this is a 2 1/2 way
with a super tweeter. This was smooth with nearly as much bass impact.
But very detailed. Much more coslty too. But it wasn't as 'lively' sounding.
It didn't like to be driven hard....or at least in that room. But it was
a helluva nice sound.

So based on this audition in an unknown room, with unknown gear
with some new tunes (grain of salt) I'd say this was a nice driver. :P
I was told the mid-bass cross was about 350Hz.

[villastrangiato]

The low coil inductance certainly explains the outrageously high bandwidth for a 6.5 in - but then the off axis response serves as a reminder of how useful that really is - same performance as other 7 inch drivers from SEAS and others - 20 to 25 db down at 3khz. Kinda makes you wonder what so called high end designers like Rockport Technologies see in a $500 Audio Technology midrange when half of the extended high frequency response is essentially unusable due to the unavoidable physical size of the driver's diaphragm. But then, I suspect most of the folks looking to buy a 60K pair of Rockport speakers are already primed to suspend their disbelief of the hard realities of physics - who could argue that a 500lb. living room paper weight HAS to sound better, right? :roll:

[JonMarsh]

Well, the description of a heavy copper ring below the pole piece sounds very ER18RNX'ish- the Xmax is the same, motor may be very similar, but the lower inductance would seem to indicate a difference in the VC construction or the amount of copper in the gap- less than half of the ER18RNX! Sd is less due to the phase plug- and at times I see behavior approaching the the breakup point in phase plug drivers from Seas that I don't like- at least not the metal ones! Almost the same moving mass, but different VAS and QTS, and lower QES for the ER18, too. Curious.

But this driver does look to be well controlled, and while I wouldn't justify using higher than a 2 kHz crossover point, it should be possible to do it there quite nicely- and the folks who like "sexy" may prefer this to the ER18RNX. In practice I'd say you'd have to listen to both closely to make a reasoned decision- unless, of course, this one costs significantly more- which, with a phase plug, it may well.

As Madisound and Solen don't have any, it's more or less an intellectual exercise for now.

[villastrangiato]

I suppose despite the inherent dispersion issues associated with the overall driver size (phase plug or no) the relatively flat response out to ridiculousville provides significant advantages over say the W18EX001 - no significant peaks in the passband to deal with and no need for crossover gymnastics to deal with Liberty Bell like ringing at 4.5 to 5K. So while the crossover point remains essentially the same with the poly cone - getting there should certainly be a lot easier.

And it should be interesting to see how the better damped poly cone compares with its metal coned brethren in suppressing odd ordered harmonics.

[Face]

http://www.madisound.com/catalog/product_info.php?products_id=8766

http://www.madisound.com/pdf/Idunn.pdf

[JonMarsh]

I wonder if the funny lumpy bit/dip in the response around 800, as shown in the Idunn measured performance, has any relationship to the impedance bobble in the same area? Usually that indicates a driver mechanical resonance, either in cone or surround. Unfortunate. The ER18RNX has a little bit of misbehavior there, but only about 1/3 as much.



Contrast that with this measured response of the ER18RNX in an MT.



Unfortunately the stuff the Idunn is doing there is pretty typical kind of things for plastic cones misbehavior- like the upper end of the HiVi D6.8 or Jantzen JA6008 beyond where you should use them.

They really ought to put in an impedance zobel for the network, too, IMO. Of course, they didn't ask me... 6 to one swing in impedance will have interactions with many amplifiers.

This isn't that hard to achieve.

[jkrutke]

I wonder if the funny lumpy bit/dip in the response around 800, as shown in the Idunn measured performance, has any relationship to the impedance bobble in the same area? Usually that indicates a driver mechanical resonance, either in cone or surround. Unfortunate. The ER18RNX has a little bit of misbehavior there, but only about 1/3 as much.

I think I'm going to withhold any judgement on the new U18's until they are tested by myself, you or Mark. One thing to keep in mind: that response curve is an in-box curve... and that box is the same one that Bjorn Idland used when he posted a whole boatload of in-box Seas woofer curves a couple years ago. The thing about those curves is that every single one of them had a response artifact right at the same spot. It was either insufficient internal damping or a lack of a chamfered backside woofer hole. (probably the latter)

I expect the U18's to be slightly different in performance, mainly because of the phase plug compared to the dust cap. I wouldn't mind testing one someday.

[JonMarsh]

I think I'm going to withhold any judgement on the new U18's until they are tested by myself, you or Mark. One thing to keep in mind: that response curve is an in-box curve... and that box is the same one that Bjorn Idland used when he posted a whole boatload of in-box Seas woofer curves a couple years ago. The thing about those curves is that every single one of them had a response artifact right at the same spot. It was either insufficient internal damping or a lack of a chamfered backside woofer hole. (probably the latter)

That's a very good point, John- something I overlooked thinking about that.

So, who's going to go first? Maybe some eager party will buy one and send it to you- I'm a bit tapped out on driver expenditures already this year! (too many new interesting Scanspeaks...)

[Z3Sooner]

That's a very good point, John- something I overlooked thinking about that.

So, who's going to go first? Maybe some eager party will buy one and send it to you- I'm a bit tapped out on driver expenditures already this year! (too many new interesting Scanspeaks...)

I have two sitting in my closet right now, just waiting for me to get a test rig set up. On the other hand, it would probably be much quicker to send one to John and I'm sure He'd get much better information, considering I've never tested a driver before.

John, let me know if you are interested.

[jkrutke]

Took me a while to find our discussion on the U18, but I thought I would just comment that there is indeed a little dip in response even on my test baffle. It wasn't quite as freaky looking as what's in the Idunn documentation, but it's definitely there on a rigid and well ventilated infinite baffle. It's kind of a broad dip.

Elsewhere I was pondering how this sort of response curve would sound in room, considering a peak from floor reflection often happens in the area where that dip is. I suspect it's not going to sound nearly as bad as it looks.

Aside from that dip, the rest of the driver is excellent including the top end response and tall order HD. I'm not sure if I'd prefer the ER18 over the U18. I've got an appropriate box around and I might whip something up and give it a listen.

I think I'm going to withhold any judgement on the new U18's until they are tested by myself, you or Mark. One thing to keep in mind: that response curve is an in-box curve... and that box is the same one that Bjorn Idland used when he posted a whole boatload of in-box Seas woofer curves a couple years ago. The thing about those curves is that every single one of them had a response artifact right at the same spot. It was either insufficient internal damping or a lack of a chamfered backside woofer hole. (probably the latter)

I expect the U18's to be slightly different in performance, mainly because of the phase plug compared to the dust cap. I wouldn't mind testing one someday.

[NyxOne]

Took me a while to find our discussion on the U18, but I thought I would just comment that there is indeed a little dip in response even on my test baffle. It wasn't quite as freaky looking as what's in the Idunn documentation, but it's definitely there on a rigid and well ventilated infinite baffle. It's kind of a broad dip.

Elsewhere I was pondering how this sort of response curve would sound in room, considering a peak from floor reflection often happens in the area where that dip is. I suspect it's not going to sound nearly as bad as it looks.

Aside from that dip, the rest of the driver is excellent including the top end response and tall order HD. I'm not sure if I'd prefer the ER18 over the U18. I've got an appropriate box around and I might whip something up and give it a listen.

A side from this lump (and maybe the price) everything looks good on this woofer :

1. No breakup
2. Low THD (better low and high then the ER18, unless I'm wrong ?)
3. Goes deep in small enclosure (with a 6mm of xmax to back it up ).
4. 8 Ohm and 90db (average) of efficiency (based on the frequency response plot).

A pair of these in an MTM array would be really great (Goes deep, efficient with low THD)! 8)

Most go ... buy ... two pair NOW!!!

Chuck