SDA 2

oldrocker

Just got them picked up and playing. It seems the right speaker outside mid driver is weak. Going to swap it out and see what is up. I think these are the "Real Wood" 2's not sure yet. From the pictures you can see the grill cover has come loose on the side. The tops are not as bad as I imagined. Didn't pick up any smoke residue with a quick cloth wipe. Push test on the drivers seemed a bit fast as compared to my other Polk's, I have to make a quick cable. However, on the bottom wood it appears someone put on some "sliders" to be able to move them around. All and all, I think the Wife did good for what she paid for them.

And as always, any advice is most welcome.

oldrocker

That mid driver MW6511 in question appears dead, I popped in one of my extra MW6510 and all seems well. Question, will it hurt anything to leave the 6510 in for a while until I can get a 6511?

oldrocker

This is the culprit.

MrBuhl

Nice! Look like the real woods to me! Wish mine were - I have studios. Someone else will have to answer on the mid-woofer.

oldrocker

MrBuhl wrote: »

Nice! Look like the real woods to me! Wish mine were - I have studios. Someone else will have to answer on the mid-woofer.

Thanks, probably going to give them to my daughter once I get them back up to "snuff".

Any thoughts on a value on these, I've seen various under $300.00.

F1nut

I believe I already told you those are SDA 2B's.

They came with plastic glides nailed to the bottom, if that's what you are referring to.

The 6510 and 6511 are really not interchangeable.

oldrocker

Thank you for the info and clarification.

F1nut

A bit more info for you.

6510 is a 6.5 ohm driver.
6511 is a 3.1 ohm driver.

You could use the 6510 until you get a 6511, but the speaker won't perform properly.

Adding spikes will result in a marked improvement. Much more so than many think is possible.

oldrocker

F1nut wrote: »

A bit more info for you.

6510 is a 6.5 ohm driver.
6511 is a 3.1 ohm driver.

You could use the 6510 until you get a 6511, but the speaker won't perform properly.

Adding spikes will result in a marked improvement. Much more so than many think is possible.

Thanks, will check and see if Polk has these a replacement.

Would you recommend spikes the same height as the "plastic guides" that are on it?

F1nut

I can't remember if Polk stocks the 6511, but I think they do. It will look a bit different, no exposed leads on the cone and no cut outs around the screw holes. You will need to make those cut outs otherwise the screws will twist the rubber surround.

For spikes, you want tall ones to raise the tweeter up closer to ear height, which should be 39" to 40". Parts Express sells 1.5" tall spikes for not much money. If you want TOTL spikes, the 2" tall Adona Multi-Element spikes are the answer.

One thing about those PE spikes, they are two piece design with the little cone **** into the main body. I recommend using Loctite on the little cone threads, so it becomes one with the main body and cannot work loose over time.

F1nut

Are you kidding me, S-C-R-E-W-I-N-G is censored!?!

EndersShadow

F1nut wrote: »

I can't remember if Polk stocks the 6511, but I think they do. It will look a bit different, no exposed leads on the cone and no cut outs around the screw holes. You will need to make those cut outs otherwise the screws will twist the rubber surround.

For spikes, you want tall ones to raise the tweeter up closer to ear height, which should be 39" to 40". Parts Express sells 1.5" tall spikes for not much money. If you want TOTL spikes, the 2" tall Adona Multi-Element spikes are the answer.

One thing about those PE spikes, they are two piece design with the little cone **** into the main body. I recommend using Loctite on the little cone threads, so it becomes one with the main body and cannot work loose over time.

Last I read Doro's post indicated they still make and sell them... however its quite old so it might not be accurate

These are the only drivers, aside from the RD tweeters, being manufactured to support vintage products, such as, Monitor, RTA and SDA. You should print this as a reference and keep it handy for the values it contains. There are no grill parts, cables, crossovers, plates or anything else available for the older loudspeakers, unless you know the Polk G O D.

1 Driver Type Q BL Compliance DC Resistance Fs

3 MW 6501 1.47 5.96 N 3.25 E - 3N/M 7.75 Ohms 31 Hertz
4 MW 6502 1.97 5.16 N 1.47 E - 3N/M 3.52 Ohms 44 Hertz
5 MW 6503 1.82 5.24 N 3.55 E - 3N/M 6.54 Ohms 29 Hertz
6 MW 6509 2.1 4.57 N 3.54 E - 3N/M 8.97 Ohms 30 Hertz
7 MW 6510 1.39 6.32 N 3.41 E - 3N/M 6.57 Ohms 31 Hertz
8 MW 6511 1.405 4.34 N 3.496 E - 3N/M 3.13 Ohms 29 Hertz
9 MW 6512 1.905 4.99 N 1.588 E - 3N/M 3.466 Ohms 40 Hertz

oldrocker

Thanks guys...

oldrocker

Finally made a connect cable. The whole array effect is nice to have going.
I have noticed the highs a tad bright in this series of speakers.

leftwinger57

It is amazing to me that most all of the mid woofers look exactly the same but clearly have different resistance values. Friends say when I show off my 2Bs that the outer one 6511 does something special and do not let the look fool you. I would not leave an unmatched woofer in there for any prolonged amount of time. Find that 6511. My side fabric was peeling from the top and back but not as bad as yours. I think they should have made it a veneer of at least white oak to match the tops. Still a nice looking set Old Rocker ,now on to the rdo-194 tweeters and so on....

oldrocker

LW, You are correct on that one.

Just spoke to CS, a nice guy and the new driver is on the way. CS stated they have about 148 MW6511's in stock. He also said to use 4 small black washers so the gasket?? doesn't tear. I figured I'd ask here for clarification when it comes in.

oldrocker

I can almost get the fabric tucked back in but I'll just call PE and get some new. Go figure I'm a few inches short on the roll I got left over from the last project....

pitdogg2

if you do not cut the gasket back a bit no washer will keep it from twisting...ask me how I know?.....you want to make sure all rubber will NOT be under a screw OR washer...

oldrocker

pitdogg2 wrote: »

if you do not cut the gasket back a bit no washer will keep it from twisting...ask me how I know?.....you want to make sure all rubber will NOT be under a screw OR washer...

Thanks PD2, good to know.

F1nut

I think they should have made it a veneer of at least white oak to match the tops.

I've seen many attempts at replacing the cloth sides with wood. Everyone of them looked like poo because the cabinet design does not lend itself to having wood sides.

Personally, I like the cloth.

TennMan

I like the looks of wood tops and bottoms. with black cloth on the sides that stops at a 2-3" wood strip at the rear edge to match the wood tops. I think that might have been standard on some of the bigger SDAs. If I ever have to redo the cabinets on my 2Bs (w/wood tops) that is how I'm going to do them.

oldrocker

New 6511 is in


Rubber trimmed back, installed and sounding great.

Was a bit "tedious" but it's done.

oldrocker

Did not think I'd hear this type of improvement
but I can hear a difference on that side.
Is there a break in time on the 6511's?

westmassguy

oldrocker wrote: »

Did not think I'd hear this type of improvement
but I can hear a difference on that side.
Is there a break in time on the 6511's?

There will be mechanical break-in. How long it will take, depends on how often they're used. They may never match exactly. 25+ years is long time. Different materials and manufacturer.

oldrocker

Second guessing myself here. There is 2 wires, one is blue one is green, which one is the positive..

westmassguy

Blue