Great Plains Audio basically is Altec without the corporate logo. They are the same staff, using the same tooling, and the same chassis parts, as the former Altec repair station in Oklahoma City. (Altec moved there after the Northridge earthquake destroyed part of their production facility in Los Angeles.)
That said, AE and GPA/Altec are quite different bass drivers. The Altec/GPA 416 and 515 are old-school 15" drivers with high efficiency, low Qts, and limited excursion by modern standards. The underhung voice coil and option of Alnico magnets is also quite unusual by modern standards, although very common back in the 1950's.
The Acoustic Elegance is a very modern low-distortion, low-inductance, long-excursion driver, with extended bandwidth a design feature of several models. The net efficiency of the AE and GPA 416 are about the same, around 97 dB/metre/watt, but the T/S parameters are different, as well as the sonics.
Both AE and GPA are quite different than modern prosound 15" drivers with 500-watt power ratings. Modern prosound drivers have voice coils with very high heat-dissipation ratings, and somewhat heavier cones. The closest rough equivalent to the AE and GPA drivers would be 15" drivers intended for professional monitor use (and marketed as such in the literature).
In other words, the AE, GPA, and modern studio-monitor drivers all sound and measure differently, and use quite different construction techniques. My quick take is the modern drivers often have rather aggressive breakup regions above 1.5 kHz, and are really intended to used in 3-way systems or with high-slope active crossovers (the de facto standard of the prosound world). By contrast, the region above 1.5 kHz is surprisingly smooth in both AE and Altec/GPA drivers, so they can be used with moderate-slope passive crossovers if desired.
AE has a lot of different offerings, but I can only vouch for the TD15M in mid-bass and mid-range application.
I have had a pair of TD15M for several years and really like them. They are not low bass monsters and never were meant to, but play well into the 1-2kHz range. I have them in a two-way setup comprised of 4.5cu.ft (128 liters) reflex cabinets with a tuning around 40Hz and they do great midbass and midrange. They are crossed-over to a BMS 4550 on QSC waveguide at 1250Hz, LR4. I use a miniDSP and bi-amplification, 4x 25W 50ASX2 ICEpower modules, but I'm sure they'd be relatively easy to design for passively. Their high sensitivity and power handling (for home use) makes them able to play "stupid loud" if needed and they'll mostly be coasting along with more normal listening levels. When planning that build, I also considered GPA 416-8C.
I did buy them back when the Canadian dollar was on par with USD and was able to get cheap shipping to a sate-side PO box since I'm 30 minutes away. I can imagine various exchange rates and overseas shipping must be daunting for something you can't even demo locally.
I have had a pair of TD15M for several years and really like them. They are not low bass monsters and never were meant to, but play well into the 1-2kHz range. I have them in a two-way setup comprised of 4.5cu.ft (128 liters) reflex cabinets with a tuning around 40Hz and they do great midbass and midrange. They are crossed-over to a BMS 4550 on QSC waveguide at 1250Hz, LR4. I use a miniDSP and bi-amplification, 4x 25W 50ASX2 ICEpower modules, but I'm sure they'd be relatively easy to design for passively. Their high sensitivity and power handling (for home use) makes them able to play "stupid loud" if needed and they'll mostly be coasting along with more normal listening levels. When planning that build, I also considered GPA 416-8C.
I did buy them back when the Canadian dollar was on par with USD and was able to get cheap shipping to a sate-side PO box since I'm 30 minutes away. I can imagine various exchange rates and overseas shipping must be daunting for something you can't even demo locally.
Acoustic Elegance Woofers
The Acoustic Elegance TD-12S serves in my Pi Speakers 6Pi Cornerhorns and 3Pi center channel and surrounds. All were measured using the Dayton Audio DATS and produced uniform results that closely matched the manufacturers specifications. The frequency response is flat on axis well past 2kHz and the impedance measurements indicate no spikes or anomalies. Build quality is excellent and the woofers have had no operational issues in over five years of use. My experience with the TD-12S led me to build four sealed subwoofers based on the AE SBP-15 and these proved to be excellent as well.
Some other subwoofers and woofers that I have experienced include SB Acoustics, SEAS, Vifa, Eminence, CSS, Dayton Audio (Ultimax and Reference series), Stereo Integrity, Aurum Cantus and others. A number of the competing speakers showed substantial variations between samples and/or from the published specifications. None of the 12" to 15" woofers that I have used have been better than the Acoustic Elegance products in any significant aspect except for Xmax. Acoustic Elegance woofers offer performance commensurate with their cost.
The Acoustic Elegance TD-12S serves in my Pi Speakers 6Pi Cornerhorns and 3Pi center channel and surrounds. All were measured using the Dayton Audio DATS and produced uniform results that closely matched the manufacturers specifications. The frequency response is flat on axis well past 2kHz and the impedance measurements indicate no spikes or anomalies. Build quality is excellent and the woofers have had no operational issues in over five years of use. My experience with the TD-12S led me to build four sealed subwoofers based on the AE SBP-15 and these proved to be excellent as well.
Some other subwoofers and woofers that I have experienced include SB Acoustics, SEAS, Vifa, Eminence, CSS, Dayton Audio (Ultimax and Reference series), Stereo Integrity, Aurum Cantus and others. A number of the competing speakers showed substantial variations between samples and/or from the published specifications. None of the 12" to 15" woofers that I have used have been better than the Acoustic Elegance products in any significant aspect except for Xmax. Acoustic Elegance woofers offer performance commensurate with their cost.
I like the DE250 a lot as well. I really like the CO380M as well. They were in my PA for a few years before I sold it. Tested at home, they were great. I was foolish to sell them, but I have no project to use them in and have too many drivers on the shelf.Thanks Brett. Funny - i also consider to use mentioned Beyma CP380M in that design (I hesitate between that Beyma and B&C Speakers DE250 or B&C Speakers DE500).
To be perfectly honest, I don't know. I run them louder than I should regularly I'm in an apartment) and haven't noticed it. I don't think I've ever seen any of the 15's move more than a mm or 2. John reckons it's not an issue and neither does Nick, who originally designed them.
Beyma, but not by much. I use DE25 (mains, Unity) and DE250 in the surrounds now.
I have SBacoustic locally, however 4pcs AE Dipole 15 is something I'd like to buy for open baffle, but $425 shipping cost plus 40% customs fee (estimated $2.7k total cost) is still not on my count yet.
anyway, looking at early 2008 post, it seems that AE driver was alot cheaper.
They aren't listed on their product webpage at this time. (..they made and sold a few, but I suspect that it isn't a priority.)
Plus, there is the JA8008-HMQ (in an 8") for about $200 Euros - and it "fits" aesthetically with the AE woofers.
There are also a fair number of other choices available from multiple sources, and they certainly don't have to be $200:
ex.
Driver Detail | Tymphany
Good points. I have long been interested in the TD8M but the lack of published data (frequency response, etc), scarce user comments and high price have made me not to act.
AE woofers are generally regarded as reaching higher than others of the same diameter in a nicer way. Vapor Audio uses a TD10M crossed at 1.1kHz to a TPL150H which is a good indicator that maybe I could cross a TD8M at 2kHz to the TPL150H. Much lower Le than most alternatives, plus the higher reach from the curvilinear profile. Sensitivity a little shy for my needs...borderline.
Oh well, I wish they published more data.
BTW, how well does that Tymphany sound vs the better mids you know? Thanks for the pointer.
Recently AE sent me this info about the TD8M. I also have data for TD6M if you're interested.
Attachments
This is great! Thank you!!
Either you are a lot convincing than me or AE has shifted gears. I was in touch with them a couple years ago and they were not willing to share data.
That FR confirms my suspicion the TD8M could be crossed at 2kHz nicely to a TPL150H. I'llamame give them a call to think through the combination of impedance and sensitivity - both too low for SETs.
The JA-8008HMQ, because of its rising response from 800 to 1.8 kHz, on a small baffle profile with enough diffraction gain could easily be a driver that's 98-99 db "efficient" from about 600 Hz to 1.8 kHz (with enough output below 600 Hz and enough linear excursion) to avoid an electric high-pass filter.
http://www.jantzen-audio.com/wp-content/uploads/2013/06/JA-8008-HMQ-Woofer.pdf
The Dayton Audio midbass PM220 and 180 are also similar, but don't have as linear a response above 1.8 kHz. The updated 6.5" fullrange variant does (up to a bit over 3 kHz):
https://www.parts-express.com/pedoc...Full-Range Neo Driver Specification Sheet.pdf
As for the Peerless driver, I've never heard them. I can say though that their newer motor/suspension designs have generally produced some rather excellent midrange non-linear distortion results (..and that I'd guess it included that 8").
..I'd probably choose the updated Dayton 6.5" fullrange with that sort of design (..though this is assuming you can deal properly with it's response above 3kHz).
Thank you!
The Jantzen really has a rising response. I can correct through DSP, but would end up correcting to the lowest point. Plus it's expensive and difficult to source.
The Daytons are interesting. Did not know these. Have you heard them? I can manage above 2kHz with steep active xo and also correct the rising response. These are rather cheap and could also consider MTM to increase sensitivity and connect in series to increase impedance. In fact lately I've been looking into several fullrangers for this purpose, but in TMWW configuration. Likewise for Peerless. I guess my biggest point is how they sound vs dedicated midranges.
BTW I wrote to AE about TD8M.
Cheers!
I've not heard them. I've seen good reviews on them and bad.. (..and most of the bad is directly related to running fullrange). I have recommended the 8" before without reservation when it was used below 800 Hz.
They are however very well engineered (with good non-linear distortion and a nice flat impedance.)
I'd personally prefer a dedicated midrange (if it runs into freq.s above 1kHz plus).. but it really depends on how it's used.