0-10-20-30-40deg Horizontal no baffle 30cm away through 0.477uF series, 62uH parallel. Y axis divisions 5dB
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Indeed even if worked loose at the end of their travel nothing changed in the impedance and frequency plots after those magnet to chassis original self tapping screws got replaced with well tightening brass and nuts. But its worry free now for reliability against vibrations or for knowing it will go back together well when changing a diaphragm assembly. Speaking of which they are probably the main variable. One channel's dome tweeter got replaced for a Faital horn already BTW. A no way back HF hack operation 🙂
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The 1425
Compare to this Great Plains Auduo Altec 288
Look at all that hash and garbage with the copy Altec lol
Damn that is impressive. Do you have a CSD of the Community M200 (or M200a)?
Tried just one channel's top cab with a DSP crossover. Subjectively this CD+Horn combo sounds neutral without any harshness or weird consonants. Coverage is very even. Repeating that with passive is easy enough to cross alike but to just dial in some LF delay by clicking the mouse is rather impossible. 😀 It will be tricky to somehow balance it out as a whole...
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Listening in stereo with passive crossovers and the pedestal bass cabs for a couple of days now. I managed to acceptably scatter the mid-hf geometrical delay by sticking a 100uH coil in series with the shunt capacitor in the second order electrical filter for the PHL. That hits the low pass phase for a sharp turn beyond the 24dB/octave acoustical slope delay. Done that higher than the low pass crossover's point. In combination with asymmetrical -6dB frequencies it works over a wide enough area to avoid audible troughs. 2.1kHz for the mid 2.6kHz third order electrical for the horn. Six elements no resistors. Just a 0.07 Ohm DCR EI frame coil inside the bass cabs. Those Tangband ovals are car stereo subs and droop further. It ended up as a 6 Ohm 94-95dB sensitivity, although slim DIY speaker, with even coverage from 30Hz to 20kHz in room. Very convincing sound with great tonal balance and dynamics given the form factor and room size. No hint of honk or harsh. Thanks for the info on the drivers guys. Special thanks to POOH. If the crossovers will remain long enough out of the box I am in danger of getting a couple of CDX1730 to also try though. Just because all he said about the CDX1425 proved 100% true. But its also so good now and it took much work to focus it well on passive filters. So I better get those Xovers inside soon before the bug bites and I will have to redesign for yet another CDX specimen then 😀
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Here is an RTA graph at one random point in space four metres away at about the sofa area when both speakers are playing. Warts and all 1/48 octave band, just holding the mic at sitting ear height with me behind. The room is a sparsely furnished less than 30m2 living room with hard walls and concrete floor construction. Acoustically fully untreated of course 😀
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The 1730 isn't necessarily better, I like it because it mates up well with the Community M200 midrange better than the 1425. I have the 1425 back in the big rig now mated with a large format aluminum compression driver and prefer it over the 1730. The 1730 is soft and velvety where the 1425 is really clean and dynamic.
I see that the 1730 has the classic back inverted dome and annular slots construction. Does it place its voice coil further back than when mounting a 1425? Because in my case with the passive cross and fixed in cab positions, some extra Z plane delay may prove critical to can not tackle it anymore.
Looks good!But hmmmm.... I think you should seriously consider starting a completely NEW design from scratch
. Only to present us with new speaker project 
I have designed enough pro loudspeakers in late years. For installations. Although making big new personal speakers every now and then isn't an expensive hobby here in South Switzerland economy, I am just being lazy 😀
These Celestion HF revised towers have the form factor and sensitivity that I need while covering my room great. I still fine tune them so to extract as much of a monitor tone possible. Never be hasty with finishing speakers. Because wrongly assumed ones detune our ears. I am expecting a pair of AKG K612 Pro mastering headphones to compare the tone better also before calling them done.
Mentioning headphones, I have developed from scratch a new line preamp with gain and high bias output stage that can drive headphones too. It took much lab work. Its apparently very good but not finished for a PCB yet. It can't be finalized in details before PCB tested so to present it. I had arranged for a prototype PCB development so to finalize it but it took unexpected long delays. I am calling it DCG-3. There are two beta testing martix board proto units made by friends already.
These Celestion HF revised towers have the form factor and sensitivity that I need while covering my room great. I still fine tune them so to extract as much of a monitor tone possible. Never be hasty with finishing speakers. Because wrongly assumed ones detune our ears. I am expecting a pair of AKG K612 Pro mastering headphones to compare the tone better also before calling them done.
Mentioning headphones, I have developed from scratch a new line preamp with gain and high bias output stage that can drive headphones too. It took much lab work. Its apparently very good but not finished for a PCB yet. It can't be finalized in details before PCB tested so to present it. I had arranged for a prototype PCB development so to finalize it but it took unexpected long delays. I am calling it DCG-3. There are two beta testing martix board proto units made by friends already.
Glad to read about your new developments despite living in South Switzerland economy. High sensivity speakers is what I'm after and I would certainly build something like your towers. But I know some of these drivers are bastardized and not that available anymore. I haven't seen many DIY >95 dB sensitive designs lately. The only desirable for me being Troels TQWT. Price is an ouch and I'm hoping to move to a new home in a year or so. It's wiser to wait and see what my new environement demands.
Well, I would recommend you spin your own because any preset speaker will never give you the adaptability freedom that DIY gives in your particular installation environment. Bastardized was only the old tweeter, but another problem is that the PHL company is in limbo so no nice 1120 mid to get as for now which I would surely recommend over the 1220. It will not make a self sufficient satellite upper section to can just carry it over and use in a small room like in my case but I don't think this concerns you. I would not snub the humble and affordable B&C 6MD38 though, a very nice mid driver. The ovals are still around. A critically damped reflex bass section or aperiodically damped depending on your room modes and positioning with those ovals or two nice eight inch rounds of 30-35 Hz Fs that would also go higher in the mids for more crossover choices, a three liters well damped mid cavity for the B&C, and set the Celestion's center at one meter height from the floor. Start with a miniDSP to weigh the curves initially and when kinda certain try to go there with a passive so to avoid multiamping and the cheap DSP in the chain. But you have a quickly mapped out path to follow, not shooting in the dark. Then you fine tune. In the end you will be having more precisely what you need and you will come out much more learned and proud than adopting good designs that have been developed in another room to someone else's equipment and taste. Its hit or miss with the ready designs.
Thanks for recommendations. I will certainly have them in mind as an option. For the moment this all DIY (xover and drivers choice inc.) path looks like... well a path that I would have walk not in my shoes. Like 3 sizes bigger or something. More learned, proud, rewarding surely, but too many challenges in life at the moment to cope with another that big. That's why I was looking for a rewarding kit 🙂 I also found something that looks like a jbl discount and in my region: JBL STUDIO 590 - Audiotrendt 1280 euros a pair.
If you will find a way to get those on good discount its no more hit or miss than building another's renowned DIY for comparable spending. The flimsy plastics and the proverbial JBL treble liveliness aside there is much engineering packed in those 590s for the price. A steal for Americans on Amazon right now. Less than a grand for a pair.
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