KeithR's "Dream Speaker" Search

[Robh3606]

A friend has designed a conical CD horn with tractrix roundoff and 75x45 dispersion, which is very promising
target is CD qualities with equally even impedance load pattern as my JMLC 270
listened to it on tuesday with JBL2450 SL with Truextent be dias

If you can get a pair 476Mg diaphragms they don't have as much roll-off as the Be version and if you really want to go tweeter less it's another option.

Rob

 

[Robh3606]

Second, assuming equivalent drivers, the on-axis efficiency of the Avantgardes will be higher. This is because at the top end of each horn-loaded driver's range (which is usually the limiting factor for a horn-loaded driver's practical efficiency), the output is being funneled into a relatively narrow pattern, and narrower pattern = higher pressure (in fire hoses and in horns). In contrast the style horn I prefer aspires to constant pattern width all the way up, which doesn't really happen without a diffraction slot (like the Thrax horn uses). Anyway to the extent that there is a causal relationship between on-axis efficiency and dynamic contrast, seems to me the higher-on-axis-efficiency horns of the Avantgardes would theoretically have better dynamic contrast.

Hello Duke

Ok I see what you are saying. I see it a little different and look at it from the overall power response.

All the dynamic contrast is set by the driver and non CD horns have a falling power response.

If you look at it from a sound power into the room perspective CD's have a distinct advantage over non CD horns because of the much smoother overall power response.

They actually put much more HF power into the room. I think that is more important than any on axis sensitivity increase you may get but to burn through the "noise". I think that the "noise" of a CD system would more closely follow the dynamics because of the flatter power response.

If Geddes and Griesinger are right, then maintaining pattern control down to 700 Hz is really good. I'm not saying pattern control down lower isn't beneficial, but I don't think the system will suck if it has a 15" woofer or two instead of a real midbass horn.

I think they are correct as well it just that many see a horn loaded system and think because it is horn loaded it has directivity control over it's whole range when in fact it doesn't.

Rob

 

[Folsom]

I think it would be nice to have a switch to flip between dynamic and less dynamic. IMO no matter what you do, dynamic can be hard to have playing all the time. Sometimes background music is nice, and no one would contest that really dynamic background music is a total nuisance.

 

[Duke LeJeune]

... with high precision throat adapter that follows as a natural extension of the 4003 exit...

YESS!! Good for you, for paying attention to getting the junction between compression driver and horn right! Contrary to popular opinion (I say that as if opinions about horns enjoyed some sort of popularity), you can't mix 'n match horns 'n compression drivers and expect to hear what either is capable of unless the transition between them just happens to be benign.

A friend has designed a conical CD horn with tractrix roundoff and 75x45 dispersion, which is very promising... target is to try and avoid tweeter

I like your constant directivity and your pattern and imo "no tweeter" is a very worthy target. The ear is sensitive to phase pretty much anywhere you are likely to find a crossover between a midrange horn and a tweeter horn.

will be even better in hf with TAD 4003 which is next protostage

I tried going tweetless with a TAD 4001 years ago with disappointing results, but I think the 4003 is more promising and your 75 x 45 horn is also more promising than what I was doing.

Very best of luck to you on the project!

 

[Duke LeJeune]

If you look at it from a sound power into the room perspective CD's have a distinct advantage over non CD horns because of the much smoother overall power response.

I totally agree. Imo this matters much more than dynamics. I think the most important job of any speaker that aspires to "high end" is to have a good frequency response, and unless one listens well into the nearfield, the power response is part of the perceived frequency response.

 

[morricab]

If you can get a pair 476Mg diaphragms they don't have as much roll-off as the Be version and if you really want to go tweeter less it's another option.

Rob

Pretty rare?

 

[morricab]

YESS!! Good for you, for paying attention to getting the junction between compression driver and horn right! Contrary to popular opinion (I say that as if opinions about horns enjoyed some sort of popularity), you can't mix 'n match horns 'n compression drivers and expect to hear what either is capable of unless the transition between them just happens to be benign.



I like your constant directivity and your pattern and imo "no tweeter" is a very worthy target. The ear is sensitive to phase pretty much anywhere you are likely to find a crossover between a midrange horn and a tweeter horn.



I tried going tweetless with a TAD 4001 years ago with disappointing results, but I think the 4003 is more promising and your 75 x 45 horn is also more promising than what I was doing.

Very best of luck to you on the project!

Going tweeterless was one of my goals as well and why I ended up with the CP755Ti. In the CD horn I use it needs a bit of EQ to flatten up a bit but the overall sound is extended and airy. I think with something like a JMLC I could do without the EQ.

 

[christensenleif@msn.com]

I think it would be nice to have a switch to flip between dynamic and less dynamic. IMO no matter what you do, dynamic can be hard to have playing all the time. Sometimes background music is nice, and no one would contest that really dynamic background music is a total nuisance.

what´s background music?

 

[christensenleif@msn.com]

Going tweeterless was one of my goals as well and why I ended up with the CP755Ti. In the CD horn I use it needs a bit of EQ to flatten up a bit but the overall sound is extended and airy. I think with something like a JMLC I could do without the EQ.

since we´ve got plenty of sensitivity and I do passive X/O we "flatten down" by reducing level from 550 and up...."deductive eq" only

 

[Robh3606]

Hello Morricab

They Mg and Be stock diaphrams for the 476 are rare and are only used in the statement speakers with no Pro equivalent. I have never seen one as a separate only drivers. I am sure though if you know a dealer you may be able to get a pair. You could try the guys that sell the M2 components at least they should be able to confirm if you can get them separately or if they are only warranty repair items. Can't imagine ever damaging one at home.

Rob

 

[KeithR]

It's funny that this thread is on the home page...but that isn't a picture of my Zus even when I owned them years ago.

 

[spiritofmusic]

Oh Keith, I spoke w Steve and Ron, and we thought it was only right. Come back to Mama.

 

[spiritofmusic]

Here's the latest room pics, guys (I'm not afraid like many here)- I've finally finished speaker positioning leaving them 10' from the listening position and approximately 7' apart (inner corner to corner) with the speakers 22" from the front wall. I added curtains to cover the paned glass on the rear wall which had very positive effects and allowed a few inches wider spacing. I've put up some GIK art panels behind the listening position and one to the side (temporarily at least).

I really don't think a horn loudspeaker works on this long wall configuration as the integration would be super tight. Wider spacing results in a flat image with holes. I also tried the speakers a few inches into the room as well as the sofa moved in a few inches and both ways resulted in a "in the soundstage" result that sounded fake. I'm sure some 'philes like that however.

I will say I'm getting excellent sound - it took a month - but I'm there.

Excellent Keith. It only took me 6 years, 2 changes of room and a small fortune to get my Zus to disappear, image, be seamless etc etc yada yada. I beat yr 1 month by 71 months.

 

[KeithR]

Oh Keith, I spoke w Steve and Ron, and we thought it was only right. Come back to Mama.

heard the new Def has now slipped into 2020...Sean-time, but of course. there is a Dominance 2 that took precedent allegedly, but it wasn't done in time for CAF either. must have been a special order or something.

 

[spiritofmusic]

The longer the better. Zu are the anti-Raidho.

 

[spiritofmusic]

Keith, the most amazing thing about this thread is that it's made it to 104 pages, discussing a max of a half dozen models, none the sexy attention grabbers normally obsessed over on WBF. And you're nowhere nearer a decision.

Congrats Lol.

 

[morricab]

since we´ve got plenty of sensitivity and I do passive X/O we "flatten down" by reducing level from 550 and up...."deductive eq" only

Since I am doing boost or cut digitally, I didn't really think it makes much of a difference but I could try a cut rather than a boost and see if there is an audible difference. Given that I am listening at levels typically not so loud (occasionally up somewhat though) I figured that boost should not correspond to a significant distortion component since the driver is so sensitive.

 

[morricab]

Hello Morricab

They Mg and Be stock diaphrams for the 476 are rare and are only used in the statement speakers with no Pro equivalent. I have never seen one as a separate only drivers. I am sure though if you know a dealer you may be able to get a pair. You could try the guys that sell the M2 components at least they should be able to confirm if you can get them separately or if they are only warranty repair items. Can't imagine ever damaging one at home.

Rob

Based on my reading about these drivers, I think I would prefer their sound to the driver used in the M2...if a pair could be obtained that is...

 

[jeff1225]

Based on my reading about these drivers, I think I would prefer their sound to the driver used in the M2...if a pair could be obtained that is...

The compression driver that's used in the M2 is what you heard at my house Brad.

 

[KeithR]

Keith, the most amazing thing about this thread is that it's made it to 104 pages, discussing a max of a half dozen models, none the sexy attention grabbers normally obsessed over on WBF. And you're nowhere nearer a decision.

Congrats Lol.

that's not entirely true as I've documented/learned an exceeding lot over the past year and, in fact, declined to purchase several speakers and have decided horns probably aren't for me.

i know everyone wants the shiny new box in my room and to congratulate my purchase, but its not so simple. a room change was also a big, new factor (as discussed in the OP) that was ultimately going to sway my direction and timing. I opted not to purchase anything before the move.