[nvrgdenuf]

 Seeking some input about an open baffle design similar to the Emerald Physics CS2, but using an 8 inch full range instead of the wave guide with compression tweeter. For instance the Jamo 909 which has a mid and tweeter. I have not heard the CS2, but wondering about any similar design, where the x-over is so high. It seems a regarded Fostex or Hemp would have better tone from a lower x-over point, such as 180hz, compared to listening to the Alpha 15 up to 1k Hz. I have used the Silver Iris 15" coax and dynamics were great, but midrange wasnt equal to my 207e or HempTone 8 FR.
 Not sure I want to buy the DDS waveguide for a comparison, so just just seeking some opinions. I figure someone here has tried both or similar.
thanks

[Magnetar]

 I have several 15" coaxials here but don't use them. Beyma. Altec, Tannoy, URIE, PAS, EV..........




I agree with the lower crossover point but feel a better way to build a small footprint fullrange (all but bottom octave) OB system is to use a 21" woofer, a good 10 or 12" (here we have the killer 12" EV SRO Alnico beast) covering from 180 to 1600 cycles, then a complex conical (Emilar EA175 driver, aluminum diaphragm with mylar surround - like Radian) horn to 15K and then a horn loaded super tweeter both loaded with compression drivers. You could do without the super tweeter but all the 1" drivers I've used (lots including TAD) never sound right on the top octave. The super tweeter compression driver here is actually a rare type being a ring radiator. The inexpensive B&C DE10.

These were the best sounding speakers I've built (TONE!) until I built my HEEA! line OB's

[Brucemck]

Magnetar, what's your favorite "supertweeter"?

If you were going to augment the high end of a Festrex d5 above 7k to 12k or so, what would you recommend?

Have had recs for Raal's in a waveguide, or, for Fostex T500, both not inexpensive

[Magnetar]

I never had the RAAL but have used Auram Cantus and Raven tweeters. The RAAL claims to be better but I don't see why, maybe the transformer. I have had some Fostex bullet tweeters. I think you'll find the Ribbon out of the waveguide's HF energy in the room will be more open sounding with a bigger sweet spot as long as you aren't standing. It will not match the narrowing directivity of the Feastrex in the treble though. Putting it in a waveguide will fix that and bring other problems. I have never heard a ribbon properly horn loaded. If I were to do this I would use the smaller, shorter ribbon due to the larger ribbon flexing when loaded in the throat because of it only being attached on the top and bottom.

The Fostex I used was the T90A. It's really quite good and it's radiation will match the Feastrex better. Off the shelf I feel you'd be ahead with a Fostex tweeter (ring radiator) - The little B&C I used in the speaker shown is a ring radiator modified slightly to work in the little Eminence horn. It is of the same, maybe better, quality (more sensitive) as the  T90A. I feel the Fostex is the better choice 'off the shelf' for your application over the ribbon in a waveguide. Ribbons also seem to compress transients compared to the Fostex. A big cymbal splash won't have the live sound, it will sound good but not as 'there' or present like it's being played back through a compressor. This will be mostly noticed when listening to a good LP or SACD disk.

My favorite tweeter (actually I use them down to 800 cycles) is the RTR HF100 electrostatic panels with the right power supply, transformers, in a line array and proper Rep resistor. They are as pure as a newborn baby.

[BlkNotes]

Hello;


     Magnetar I sent you a PM.


Cheers;
Stephen

[nvrgdenuf]

Magnetar,
 Just as a disclaimer, I have no idea how your speakers sound, so don't read any questions as derogatory. I am only trying to process the over abundant barrage of opinions. Those that have tried different designs and drivers have weight over those that haven't.
 I like the sound of open baffle, because it sounds less constrained and less phony than a box speaker. It also sounds more dynamic in every way. Heck, listen to a broadcast NFL game. Also, larger drivers sound more open in that regard. The Silver Iris 15" coax I had were very open and lively but lacked some refinement I thought, but maybe the Sterling Series fixes that. I then had the 10", which didn't seem to be as good.
 I looked at 10 inch Warrior and the 12 inch Knight which are attractively priced and I thought it would be a much better bargain than a co-ax of the same size, especially given the options of tweeters and pricing compared to compression drivers. My main question would be in the sound quality of the 10 or 12 driver in the reproduction of instruments or human voice. Not just the Madison, but any of the drivers of that size compared to say a Seas or something equivalent that is highly regarded. Interest is high in the P Audio co-ax, but I wonder the same about its woofer. The Eminence B102 is suspected in the Zu Druid but not sure about OB use.
 Any thoughts here ? thanks,
nvrgdenuf

[Magnetar]

Do you have a specific range in mind for the 10" drivers? Driven by what? Mullti-amping? What have you used? Liked? Why? What do you feel is most important? What is your budget?

Coaxials tend to be compromised most at at the top of the woofer and low of the high drivers range. If you make the concentric horn larger to help the high driver you muck up the upper range of the woofer. I think this is why after years of experimenting with different models I don't listen to them. When I think I had it all solved with a coax (several times!) I still feel the 'wear' on me with lack of ultimate resolution and purity. A small 6.5" Tannoy can get very close to great but then one must add woofers to get a better foundation in the bass. The smaller coax drivers (under 12") are normally really constricted in dynamics and output too. And with most coaxials you have to eq the treble to get extended response. Even though the coax seems simple in concept it is actually a beast to get listenable for the long road.

I notice some people have stuck with the PHY coax over time. I heard them a couple of times and felt they were a bit 'toyish' in dynamics and low in resolution (pleasant masking of subtle details that invoke emotion are MIA) yet pleasant and smooth - have you heard those? I once built a nice three way to replace a pair for a friend and he is still listening to them 5 years later - a fellow that could never be happy.

Magnetar,
 Just as a disclaimer, I have no idea how your speakers sound, so don't read any questions as derogatory. I am only trying to process the over abundant barrage of opinions. Those that have tried different designs and drivers have weight over those that haven't.
 I like the sound of open baffle, because it sounds less constrained and less phony than a box speaker. It also sounds more dynamic in every way. Heck, listen to a broadcast NFL game. Also, larger drivers sound more open in that regard. The Silver Iris 15" coax I had were very open and lively but lacked some refinement I thought, but maybe the Sterling Series fixes that. I then had the 10", which didn't seem to be as good.
 I looked at 10 inch Warrior and the 12 inch Knight which are attractively priced and I thought it would be a much better bargain than a co-ax of the same size, especially given the options of tweeters and pricing compared to compression drivers. My main question would be in the sound quality of the 10 or 12 driver in the reproduction of instruments or human voice. Not just the Madison, but any of the drivers of that size compared to say a Seas or something equivalent that is highly regarded. Interest is high in the P Audio co-ax, but I wonder the same about its woofer. The Eminence B102 is suspected in the Zu Druid but not sure about OB use.
 Any thoughts here ? thanks,
nvrgdenuf

[nvrgdenuf]

Posted for driver recommendations to use up to 1.0-1.2khz in a new thread, to use with a compression tweeter and waveguide.
andy

thanks Magnetar for your time to respond

[BlkNotes]

Hello;

    PM set to magnetar.


Cheers;
BN