Originally Posted by pianoman88
Actually I was just referring to "inexpensive" (cheap!) speakers and agree with you wholeheartedly that the mid-to-high end speakers have improved. However, it seems like prices have exploded in this upper range, too.
As far as inexpensive speakers go, I've been decently impressed by the EMP E55ti speakers, as long as you've got subwoofers to carry the low end and don't need the end-all in resolution. I think they have a very balanced sound.
But i'd say it goes like this
up to 400 dollars invested - commercial speakers win
~400 - ~2k dollars invested - DIY wins
More than that - it depends on the individual designs, but commercial speakers to start to have an edge again in terms of R&D and available parts.
I'm not enough of an expert to know how multiple smaller drivers vs one larger driver really affects our perceptions of. Would be so fun to be the listener in double-blind tests and see if we could perceive a difference or not, wouldn't it?
It depends on the frequency range being covered. At low enough frequencies both will be a point source with the same aspects of distortion and output, etc, although the multiple smaller drivers will probably have more heatsinking area and thinner baffle. the higher up you go in frequency with these drivers, the more it starts to matter. THen you start getting into quasi-line sources and narrowing directivity, and even center to center spacing at the crossover - which is certainly relevant to us (IE look at the Malcom design).
Heh heh...I've been thinking about the Phils as well (though not certain which model yet) AND building a SEOS of some type, too! I'm sure many of us would just LOVE to hear your comparison of the two once you're up and running.
I'm getting Phil 2s... raal tweter, neo 8 midrange, and better efficiency than the phil 3s.
Makes sense. I've seen the SEOS waveguides designs in that forum. I don't specifically see one for the Eminence Delta12, though. Did you mean the Designer12?
No, i meant the delta12 - http://www.diysoundgroup.com/forum/index.php?topic=9.0
[list][*]How do you all decide which size SEOS and woofer to get?
Well first of all, you pick an upper bandwidth for the tweeter section. a small diapgram compression tweeter can cover the top octave with the least amount of breakup and the most extension, but will probably start to struggle below 2khz. A more typical compression driver can play down to around 900hz, although you might trade some of that top octave out. a 1.4 inch or larger compression tweeter will certainly trade that top octave out, and probably need a super tweeter if you care about the top octave. These very large drivers can play even lower - some even going down to 500hz.
I decided to go with the 1" compression tweeter, because of the same reasons as Geddes and his speakers. I want directivity control down to about 1khz at the very least, as that's where timing cues, not level cues, affect perception of imaging. This is also based on the success of Geddes' Abbey and Summa speakers. I don't know about others, but at least a few of us are inspired by his work and decision making.
Now for a crossover point around there, you need a waveguide that can hold directivity down that low. That seems to leave the seos 12 and the seos 15.
to mate to a 12" waveguide, you probably want, give or take, a 10" woofer at around 1.1khz or a 12" woofer at around 950hz. this ensures a smooth transition in off-axis response.
to mate to a 15" waveguide, you probably want the 12" woofer covering up to around 950hz or a 15" woofer around 850hz.
I personally went with a 15" woofer, so I am waiting on the poured SEOS-15s. If you can live with the size, I think the 15" two-way is the ultimate choice from a directivity control perspective. The 12" two-way probably has slightly better power handling for the tweeter, but i'm not sure it matters in a home speaker.
the 1" compression drivers can't take advantage of the 18" waveguides, so bear that in mind. the 10" and 8" waveguides can't quite get the "full effect" of constant directivity.
[*]Where can the compression drivers be found/purchased? (The SEOS is just the waveguide, correct? That is, it doesn't include a compression driver with it, right?)
Yes. However the SEOS waveguides were specfically designed with an entry angle to match the exit angle of two compression drivers - the B&C De250 and BMS 4550 - this ensures a smooth transition of sound waves. The de250 can be had from parts express, and the BMS can be had from the bms distrubutor directly. However these is also the custom drivers Erich has put effort and money into just for us, and I would give those serious consideration.
*]Do you feel it's worth building one of the completed designs like the SEOS12 with Designer12 woofer that is amazingly inexpensive given what the quality of sound will be (I think!) or would it be worth it to wait for awhile until a few more designs are out there, particularly ones that use a higher quality woofer and compression driver to get absolute top notch sound?
The tweeter in that design is fine - it's the same one Geddes uses in his Summa and Abbey speakers - the De250.
But yes, I feel that high end speakers need, among other things, is careful control of flux modulation, and what i saw of the designer series drivers is that they make no effort in that regard. I would want a woofer driver with shorting rings. I went and ordered the Acoustic Elegance TD15M, which has a big copper sleeve on the pole piece as well as a shorting ring (the Apollo upgrade takes it a step further, but i'm not sure that matters in a home environment. if it could fund a comparision, i'd love to)
I don't think you need to go all out with an AE driver but the flux modulation IMO is significant. I also think the SEOS-12 holds pattern down perfectly well enough.
[*]Do all the designs on the DIY Sound Group forum include plans for the baffle/enclosure? I guess I'm a little confused on what information is included when plans for a specific speaker build are posted. (After a month of reading, this newbie's on information overload!
No, as they've been designed in make-shift test boxes.