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After a long time I got the A7's painted and back together and they sound good. Well worth the all the work. After removing the front horn mounts I had gray paint to take to the paint store. Anyone know of plans for wings?
http://www.hostboard.com/forums/hbmc...2012/07/27.jpg
http://www.hostboard.com/forums/hbmc...2012/07/28.jpghttp://www.hostboard.com/forums/hbmc...2012/07/29.jpghttp://www.hostboard.com/forums/hbmc...2012/07/30.jpg
None I'm aware of, but the originals are simple enough. Each are cab height 3/4" plywood [no void preferred in HIFI/HT apps] and 10" wide framed with 2x2s with a single brace across the middle, though back then they really were 2x2s, so I recommend 2x3s. There were no triangulating braces like on the larger 210s because they were designed to be tied together with a pair of top baffles, so I recommend adding them plus using two cross braces.
800 VOTT
LOW FREQUENCY HORNS
GM
what kind of results can I expect?
Orange A7's ? Did I miss something they look gray to me... Even the first photo the paint is gray...
The finished cabs look great ! Nice Job !
OK I should have put them with the thread from 2 years ago which would have made sense. Probably all that lead paint dust from sanding the cabs? anyway heres the link.
http://www.hostboard.com/forums/f700...oring-a7s.html
I remember those now ! :Light bulb:
Nice work in saving a piece of history! Did you spill a beer on them already? In the second picture it looks like there is a stain. Great work!!!
but how do they sound? do you plan on a smaller port? they look great! super smooth... what are you going to drive them with?
Nice work. :Thumbs up: That must have taken a lot of time and effort - great to see the results.
In the second pic that is a water stain from me wiping the top down after spilling an ashtray and not seeing that it ran down the side,looks better now. They sound very good. Was using a fisher tube integrated but it made a poping sound so now I'm using a couple of receivers to see what I like (a marantz 2238 and a pioneer 980). Looking to go with a class A SS amp or tubes in the future. Can believe how little power they need. Smaller port or wings seem to be the next step.
Just a couple watts will get them screaming..When they were designed there wasn't a whole lot of 100-200 watt per channel SS amps..It was mostly flea powered tube amps..Quote:
Originally Posted by badtoby
Congrats on the nice job ! Love to see when a plan comes together.It makes it all worthwhile.. The wings and smaller ports should really step up the bass output on those.. :Big smile:
Kudos! nice job!
Wow--great job on your restoration! I'll be interested to hear your impressions of them after you reduce the port size and/or add the wings--I think even just reducing the port size will really beef up the bass.....
Wings should be full hight and about 10~12" wide, IIRC. Closing up the port will help the bass. Mine are currently at about 100" sq, but I'm closing them down to around 76" sq as that seems to work best for my set up. YMMV, of course.
Are my eyes playing tricks or is those dust caps all pushed in ?
Yes they are can they be replaced with out a recone?
Yes, Bill at GPA can sell you brand new dust caps for your woofers and you can replace them without doing a recone. If there's nothing wrong with the cones and voice coils there's no need to recone them......Quote:
Originally Posted by badtoby
Depends on the local boundary conditions as to how much they help with bass loading, so for all but the largest rooms or outdoors, you primarily want them to smooth out and extend the horn's response ~ a half octave since it's a much truncated 55 Hz flare frequency. Ideally you want to use the top baffles also as they will still audibly help even if there's a gasket-ed cutout for the HF horn.Quote:
Originally Posted by badtoby
GM
Thanks GM for the reply. Does that mean I would have to move the horn forward and if I did would that create a time alignment problem? Truncated, had to look that one up
FWIW I'm betting you'll like the bass more the way you have them as opposed to smaller ports. That orange was god awful!!! I bet they rocked pretty good with the ol Marantz. Those have pretty good bass.
You're welcome! Why would you move the horn? As I noted you will need to make a gasket to blend the horn to the cutout. High density open cell foam is preferred. Don't know if it's still available, but I use to buy trail pad at The Foam Store to make horn extensions to quell mouth reflections back to the throat and off nearby boundaries. Basically, a much larger, deeper variant of the M19's horn foam inset, though I didn't go out of my way to make such nice, tapered cuts.Quote:
Originally Posted by badtoby
GM
after i reduced the ports on my a-5's to 75 sq inches, and loaded them with 515 e's, the bass hit so hard , they would drive me outta my listening seat. tho i only found this phenomenom with the 'e' variant of the 515. by far more bass than my old 416's, 515g's or 3156's i tried in those cabs. the 416's were 8c's. those cabs are stuffed with 421's now and at my old father in laws..ex father in laws. look up 'a5's rock the house' here in the search...an they still do, tho now predominatably with the computer as a pre amp. i cant stress enough the importance of ample clean power, as most of the home stereos rated at a hundred watts per channel appear to me to have closer to 15 watts clean power. thus cuasing 3 or 4 woofer replacements do to over indulgence in barley pop and the simple fact that the common man associates loudness with distortion. ive proven this fact with my system playing at 130 db's and folks asking me to turn it up. no distortion..its not loud
Could the horn be placed atop the baffle and forget about the cutout?
Of course you could, just like Altec did, then you would either get rid of the top baffles same as they did or do the gasket-ed cutout due to how 'two tone'/'disconnected' they sound unless your listening distance is a 100 ft or so.
GM
Thanks again GM. You know the thought did occur to me (about the two tone sound)but then a lot of things occur to me that won't hold water so to speak so again thanks for saving me the time and trouble. Your knowledge is appreciated
You're welcome! You have to wonder what possessed them to do that other than to save having the speaker spaced up off the floor. I guess they were just trying to get as much usable LF BW out of them as they could and lost sight of the primary goal of realistic sounding vocals to match the video.
Not that some modern 'tall boy' stacks are much better in this respect, at least to my ears and one reason why I quit going to the movies over a decade ago.
GM