Hey AJ: KEF coaxes

[Dennis H]

AJ,

Seeing Andrew Jones (KEF/TAD coax guru) in a thread you linked on another forum reminded me of how much people have always praised the KEF coaxes and how hard they are to find. I did a little googling and found you can buy in-wall/ceiling versions from Onecall and Vanns. They're more expensive than the Seas coax although not terribly so considering the way the Seas price has gone up. Have you (or anyone else) listened to any of these? Are they better than the Seas?

http://www.onecall.com/ProductSearch.aspx?N=385+1079

http://www.vanns.com/shop/servlet/category/type/34/1/1.125/kef-speakers/

[Jed]

Dennis, they seem to advertise features the Seas coax does not have:

"The midfrequency voice coil is of copper-coated aluminium ribbon, edge-wound over a polyimide former to increase sensitivity by maximizing the amount of copper in the magnet gap. Chassis are of precision-cast aluminium for greater rigidity, with a vented design to improve power handling. The tall profile cone surrounds are of butyl rubber to allow greater excursion, and therefore higher output. Faraday rings are incorporated into the ultra-low distortion motor, further reducing harmonic distortion by as much as 20dB. With refinements like these, no wonder the sound is so open and natural. No wonder the action on screen suddenly becomes more compelling. No wonder you get so utterly immersed in the listening experience."

[Operandi]

I was comparing the new KEFs to the Seas when I was thinking about building the Madisound Loki. To me the Uni-Q KEF looked like the better driver on paper but I don't think thats the same unit used in their in wall speakers.

Also don't all commercial in wall speakers come housed in pre-made plastic enclosures?

[DS-21]

I would imagine the KEF in-walls have a considerably higher Q than the H1333. Probably really interesting for OB use, but enclosed they're a bit expensive to take a flyer on in the hopes they'll fit into a reasonably sized box.

[Dennis H]

Operandi, the Seas is definitely more of a known quantity. I think I read somewhere that they licensed (some) of the technology from KEF. The KEFs I linked above are the Uni-Q drivers but they may not be the same as what they use in their premium speakers. The rear enclosures are optional. You mount them before the drywall goes on. The baffle is attached but I'm sure it could be removed. The attached crossover would need to be modified/replaced if you mounted them in boxes far from the wall.

DS-21, the optional rear enclosures look pretty dinky. No idea what the Q of the drivers is.

Edit: oops, found some T/S for some of the drivers. They are pretty high Q.

http://www.kef.com/products/ciseries/cihome.asp

The ones with Q in the model number are the Uni-Q coaxes. R is round baffle, S is square baffle.

[TacoD]

Take a look at the Thiel coax drivers. Those are sold separate in Europe (for insane prices, 699 euro/ piece). But the performance is very good according to HobbyHifi.

They sell all kind of versions, shielded, with or without neodymium motor
Lautsprecher Shop


To me its the same woofer as used in the Thiel wall speakers.

[DS-21]

Take a look at the Thiel coax drivers. Those are sold separate in Europe (for insane prices, 699 euro/ piece). But the performance is very good according to HobbyHifi.

When I read the HobbyHiFi comparison test that had the Thiel as well as one of the Seas coaxes (either H1144 or H1333, don't remember), my main impression was that the Seas was at least as good and many times cheaper.

[Operandi]

When I read the HobbyHiFi comparison test that had the Thiel as well as one of the Seas coaxes (either H1144 or H1333, don't remember), my main impression was that the Seas was at least as good and many times cheaper.

Thats interesting, the Thiels are pretty well regarded. Seas makes (or at least did) a higher-end coax that isn't on the DIY market (I forget who builds the speaker). I wonder how much of an improvement it is over the Prestige coax?

[DS-21]

Thats interesting, the Thiels are pretty well regarded. Seas makes (or at least did) a higher-end coax that isn't on the DIY market (I forget who builds the speaker). I wonder how much of an improvement it is over the Prestige coax?

Gradient is the builder, and their speakers are some of the very few prefab ones that are truly excellent.

They have a different cone, the "G" fiberglass cone Seas used to offer in a separate midbass. They might also have an upgraded motor with Faraday shielding and such but I don't know for sure.

[AJINFLA]

AJ,

Seeing Andrew Jones (KEF/TAD coax guru) in a thread you linked on another forum reminded me of how much people have always praised the KEF coaxes and how hard they are to find. I did a little googling and found you can buy in-wall/ceiling versions from Onecall and Vanns. They're more expensive than the Seas coax although not terribly so considering the way the Seas price has gone up. Have you (or anyone else) listened to any of these? Are they better than the Seas?

http://www.onecall.com/ProductSearch.aspx?N=385+1079

http://www.vanns.com/shop/servlet/ca.../kef-speakers/

Hi Dennis. Yes I have. An older model Ci200 I picked up a while back on Agon for around $100 IIRC. As others have pointed out, for some reason they seem not to make the in wall/ceiling models with their latest tech, although the 3rd gen 8" now has the metal dome and lower XO.
BTW, it's DLR who you should be asking, as he has one of the midrange/tweeter coaxes from the Ref series, which have the design features that a coax should have IMHO.

cheers,

AJ

[dlr]

Hi Dennis. Yes I have. An older model Ci200 I picked up a while back on Agon for around $100 IIRC. As others have pointed out, for some reason they seem not to make the in wall/ceiling models with their latest tech, although the 3rd gen 8" now has the metal dome and lower XO.
BTW, it's DLR who you should be asking, as he has one of the midrange/tweeter coaxes from the Ref series, which have the design features that a coax should have IMHO.

cheers,

AJ

Hi AJ,

I have yet to put them into a system. I got started, but found it difficult to get a good model in SoundEasy and didn't take the time to go to CALSOD for that. I may do that this coming week as I'm going on vacation and will take my laptop for spare time I'll have. There were two issues. One is getting the phase at the low end to match measured phase. It's usually very straightforward. I suspect that the waveguide loading may actually produce a non-minimum-phase output, the first I've encountered if this holds. CALSOD will be better for checking this. The other is that even with a model, the extreme peaking takes some seriously high component values for a passive XO. I may just do it actively only in SoundEasy, since I have a permanent dedicated PC for this as well.

BTW, my vacation takes me to Treasure Island to visit my parents. You're in the Tampa area, aren't you?

Dave

[AJINFLA]

Interesting. Have you e-mailed Andrew J over @ DIYA? He's probably got lots of phase data, perhaps even on your model.
Yes, I'm near Tampa. Drop a pm if you're ever down.

cheers,

AJ