A QUICK Preliminary Follow-Up :
When the head person at GPA, Bill Hanuschak and I discussed this new custom design, he advised me it would NOT be optimal in an A7 ( 825, 828 ) enclosure, as a two - way speaker,
and Bill was right !!
My initial " quick and purely subjective " thought upon listening : this is a nice low distortion driver combination ( 515G and a 288 duplex ) for use in something OTHER than an A7 ( partial horn loaded ) enclosure. Bill mentioned a bass reflex design, and I also think a really well-designed MLTL enclosure could be a good way to use this new custom driver configuration. As a three - way with an extreme high frequency tweeter added.
The 288 with a 1.4 inch throat exit is virtually
a perfect , smooth - sounding driver, up to about 13 kHz or so. Just lovely. But for some of us, ( or myself ) I must have response that exceeds what
any 288 / 1.4 inch exit compression driver can physically do !!!
This means, if I limit myself to a two way speaker ( which I prefer ), the largest size exit of a compression driver is
one inch, so as to play music's higher highs. This means this new unique custom driver is not suitable for my preferred A7 ( 825-828 ) enclosure, as Bill initially suggested.
No problem, I can employ the same driver as a 16 inch 515G woofer only, and use the
one inch exit 802-D / 811 high frequency horn, sitting on top of the A7-8's enclosure. A two - way in a 825 front horn loaded enclosure.
I LIKE the front horn loading of an A7's woofer
a lot, even if it is non linear and is fully missing low bass. It ( to ME !! ) is exciting, and has been longer- term ( since 1947 ) mentally involving - special to hear !!
To get the full energy of the 16 inch driver as a woofer only, I needed to remove the round 212-8A wave guide we added. Why ?? It covered a fairly large percentage of the driver's woofer cone, and thus, reduced the " 100% no obstruction " energy that a 515G is capable of exerting.
Sadly, this leaves the cone's voice coil mechanism open to free air, and
I think I will have to have GPA help me with a dust cap, which then precludes any future duplex use of the 288 . So be it !!!
My primary speaker goal is to maintain the simple A7 enclosure, as a two-way, and have the partial FRONT horn loading of the enclosure's 16 inch woofer. I have no present interest in pursuing either a Bass Reflex, MLTL, or a Three - Way speaker.
All I write is totally subjective, and
just my quick impression. Kudos to Bill Hanuschak and G.P. A. for a prompt and excellent audio and business experience !! First class.
Jeff Medwin
