Leave most of the reflex portion off resulting in an improved 816 cabinet and run a separate woofer/subwoofer.
I'm considering building a pair of a7 enclosures. Are the bass cabinets ever built in 2 pieces? Humping a one-piece cabinet around my shop and up the stairs is a little much.
thanks for any input
Leave most of the reflex portion off resulting in an improved 816 cabinet and run a separate woofer/subwoofer.
Not all vegetables make good leaders.
Well Bowtie, you got my attention.
I'm good with the subwoofer part.
Just build the flare section and put it on the floor?
thanks
les
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Ah, 816. I see. I got my model numbers confused. This looks interesting.
thanks.
I'd build a pair of 816 cabs, and a pair of 18" subwoofer cabs to go below them. Something like a JBL 224x is a good match.
Some people seal off the bottom part of their 828 cabs and install an 18" subwoofer. You could just make it two separate cabs.
I run a pair of JBL 2242 with my A7's.
Particularly for hifi apps, the non-parallel horn sides of the A7 are superior, not to mention the larger mouth area. 816 has some standing wave issues.
My recommendation would be build the top half of an 825/825 combined with the reflex portion of the 816. The end result will be maybe 6 inches taller than an 816, and the sonic advantages will be well worth it IMO.
Not all vegetables make good leaders.
Or how about something like the JBL 4560 cab? Mine sound very close to the Altec 828 in the midbass dept.
They are only slightly smaller though.
I put casters on all my big Altec speakers. Makes them a lot easier to move around
Better still, compression load the truncated A7 horn [sealed off around 1.5 ft^3 IIRC], further reducing its weight and XO the 'sub' system a bit higher with as many wide BW prosound drivers/boxes as it takes to get the matching efficiency to get more 'pounding'/'boom'/'punch'/'warmth' mid-bass, lower mids where the 'let's get real' hearing perception is...........or for HIFI, just one or two 411s, 416s or similar and use digital EQ to tonally balance them out in room.
GM
edit: Stack two of them/channel to get a ~2/3rds [IIRC] 210 or 211 [loads to ~110 Hz IIRC] for the HIFI 'serious as a heart attack' folks'.
Last edited by GM; June 22nd, 2017 at 12:58 PM.
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
I don't think you should do that !!! Build A-7s out of ONE inch thick Baltic Birch. Pay a couple of high schoolers ten bucks each, to run them up the stairs.Originally Posted by les winter
The A7 will sound best with one really good amp on them, running the whole speaker, with ONE time constant, and coherency, through the amp. KISS, very well done,...... rules !!
If you "want and NEED" the lowest bottom end, do an optimized 10 foot plus internal volume MLTL with a GPA 604 in it. I hear that play lovely lows, at RMAF shows.
The A7 has different virtues, compared to an MLTL, that " I " enjoy...the partial horn load of the woofer likely does this.
If you want to hear an ALTEC properly, usually a bigger enclosure sounds best. Have fun. Just my opinion, mind ya!!
Low Ohms.......Jeff
Last edited by LowOhms; June 22nd, 2017 at 01:23 PM.
Bracing gains much more rigidity for a given weight, so if I wanted some light speakers, horns I'd build them out of braced 1/2" BB, apple or similar no-void plywood and and mass load them with a removable plate perched on top that weighs at least half the weight [preferably all] of the assembled horn, or at my level of decrepitude, the most weight I could comfortably handle alone and probably stack multiple plates.
GM
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
Thanks, Interesting Post GM !!
My 825 A7 / A5 enclosures are stock 5/8ths , and I wanted, for various reasons to leave them STOCK, and un braced.
There exists about 12 inch square " patio pavers " concrete blocks, about 1 3/4s inch thick, which weigh about 16 pounds each and are only about $1.47 each. ( Very reasonable cost per pound ).
I added those systematically, ( as I can lift 16 pounds ), and listened to my 825s. My by-ear preference was about 400 pounds added to each 825 enclosure, and 48 pounds added to my DIY crossover, seemed pretty delicious. You post is interesting.
I am sure bracing would reduce my needed mass load, but bracing was something I elected not to do. Mass loading, I have a feeling, would assist any high fidelity ALTEC enclosure, as it "does things" I would guess, that bracing alone, simply won't do .
Lotsa fun to hear and do !!
For twenty dollars, someone could systematically add 100 pounds to just one stereo side, temporarily, and it is reversible, and HEAR for themselves, what happens !!
Adding Mass Loading has improved the sound quality of every speaker I have done this to. ( 3 so far, 825 enclosure, an FMI 80 bookshelf - 48 pounds, and a large Fulton Premiere P-12 series - 96 pounds per side ).
Low Ohms......Jeff Medwin
Last edited by LowOhms; June 22nd, 2017 at 03:19 PM.
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