1984 m7's with mw6500?

wispolkboy

I picked up a pair of m7's that are mint, like they never had been out of the box. Not a scratch, grill covers tight and perfectly clean. I went to epoxy the magnets and the drivers are 6500 from 84. No stamp on the sticker just hand written date and initials.
Do all 7's have mw6500?i thought they would be 6502.
BTW the magnets are not centered at all way off by as much as an 1/8 but drivers move perfectly.

Gardenstater

What's the month? The earliest schematic we have is from 11/26/84 and that shows the MW6502, so if we have your month we'd have a pretty good idea of when they switched over from MW6500's. My 79's have MW6500 and Danish Peerless tweeters. The hole in the magnet is much larger than the O.D. of the voice coil so they can slip quite a bit and still not rub on the voice coil. The clearance of the OD to the outer pole piece and the ID to the inner pole piece is not a lot. You may be lucky for now, but you might find that it scrapes at some times, perhaps on difficult bass sections of music. You might want to just put a few short beads of adhesive that would be easily removable with an xacto knife, just to make sure they don't slip any more than they already have. You may have to realign some time in the future and being able to remove the adhesive will be advantageous. I don't think I'd use epoxy in your case because it would be very difficult to remove. I'd use some sort of construction adhesive. I like Gorilla Max Strength Clear, but make the beads very short, like 1/2" and I'd only do 3 of them per side of the magnet.

wispolkboy

Thanks for your reply!
I pulled the drive again and upon closer evaluation of the date, '82
I epoxied the driver on each side.

Gardenstater

If you get a chance snap some photos and post em. People love seeing minty examples. What tweeters and crossover schematic do you have?

wispolkboy

Gardenstater

Well they certainly do look nice! Mine are 190xx serials and have the same crossovers as yours. Are these real walnut veneer? Sometimes its hard to tell if vinyl or not, they did such a good job. Mine have different grills and pegs, with the Polk Audio on the grill and grill covers entire front. Those are attractive (custom?) stands. Are they tippy at all? Have fun doing the rest of the mods and enjoying the improvements to come.

wispolkboy

stands from amazon, $60, a little tippy, thinking of making a bigger base or making the height a bit shorter.
not real veneer, just vinyl.
I have an old NAD 7155 but i think it needs some tlc on it. it was powering some sda's 2b. switched them for the 7's

Gardenstater

My stands are 24" tall also and I find that height is perfect for my listening position, putting the tweeters right about at ear height. Honestly though I think those stands are not stable enough for these speakers and it doesn't really look like they are fillable with sand/lead shot. My stands have 2 16" x 16" concrete blocks as the base (36lbs ea) and a steel column that is filled with sand/lead shot.

wispolkboy

I like the idea of increasing the weight.... I'm thinking about a 1/4 steel plate on the bottom.... Cut to the shape and painted... Thanks for the tip

Gardenstater

I think I'd go with 1/2" steel. A 16" x 16" piece of that'd be about 36 lbs.

wispolkboy

I think I can cut 1/4" to the shape. 1/2 would be difficult.
And 1/4 on the very bottom would give a very low center of gravity.
Better than what I have now

Gardenstater

OK good luck. If you don't increase the dimensions of the base you won't get that much more stability, even though the increased weight certainly helps. 16" works great for me. If you really like the way the base looks now (rounded 3/4" MDF?), just make a bigger one and put one or two 1/4" steel plates underneath it with Gorilla Super Strength const. adhesive or the like, and maybe 4 screws.

F1nut

An even better idea, buy the 4 post stands from www.skylanstands.com

wispolkboy

F1nut wrote: »

An even better idea, buy the 4 post stands from www.skylanstands.com

Thanks for the site.... however I really don't like the look of those. (or price, lol)

Gardenstater wrote: »

OK good luck. If you don't increase the dimensions of the base you won't get that much more stability, even though the increased weight certainly helps. 16" works great for me. If you really like the way the base looks now (rounded 3/4" MDF?), just make a bigger one and put one or two 1/4" steel plates underneath it with Gorilla Super Strength const. adhesive or the like, and maybe 4 screws.

I was thinking the same as far as how to add the plates to the base.
thanks for all your coments!