Polk Monitor 10

[RodH 4,866]

Can you post pics of the crossovers?

[Sk1Bum 11,403]

Probably. I've not opened the cabinets up yet.

[Rob 5,977]

On 5/13/2020 at 11:49 AM, Sk1Bum said:

I found this schematic, and it looks like the SL2500 is the original tweeter. That brings up a couple of questions.

 

Should I decide to upgrade the crossovers, what parts should I use?

Is a crossover upgrade something an absolute novice should attempt?

 

  Polk Series 2 Monitor 10 schematic.pdf 310.16 kB · 5 downloads

 

Yes you can do it. I even tried it and I am a novice at heart. I heard that capacitors go bad over time so I decided to do this myself because a friend of mine told me it was cheaper to do yourself and an easy project. So I got all the values off the caps and resistors and made my own schematic of the crossover.

 

I put in an order at parts express and got everything I needed then put it all together. They do sound a lot better than before and the tweeters work now. Good luck and just do it. 

If the tweeters are rated for the same freq why would you have to change the cap or resistor value?

 

I found this awhile ago if it will help.

 

Edited May 15, 2020 by Rob

[BarryG 2,853]

Use the values in the schematic, replace electrolyticS sand resistors! 
12 uF electrolytic with polypropylene I used Dayton

27 uF electrolytic with polypropylene I used Dayton

2.7 ohm I used Mills!

 

you don’t have to replace the 16 uF Mylar but it does not hurt!

 

3 or 4 components per speaker!  Polypropylene caps are much larger than the electrolytic s!

 

if you can’t find correct value, use two capacitors in parallel to get correct value!

Edited May 15, 2020 by BarryG
Correction

[BarryG 2,853]

The whole crossover is probably mounted to backside of the binding post plate!carefully mark , I used numbers and unsolder the wires mine had 4 wires! Since there are 4 wires and two colors, be careful! 
Now binding plate with crossover can be move to your workbench to work on.  

[Sk1Bum 11,403]

Here are the crossover pics. Actually, I have little idea what I'm looking at.  

 

[Rob 5,977]

YEP looks similar to my CV's. Everything glued onto the back of the speaker terminal housing. Except I thought mine was a mess.  I looked at it and drew me my own diagram so understood it better with pics and went from there. I used my old soldering iron to separate the glue to get a better look at the values.

Edited May 15, 2020 by Rob

[BarryG 2,853]

I’m looking at your crossover, looks like it’s changed with the tweeter they added,  that triple stacked yellow capacitors do not look original, and the wire wound resistor value is wrong, so that all has been added!  I would take careful note of wiring locations before disassembly!  I would pull all components, double check everything even inductors, but my guess they are correct. Might not hurt to double check that the 6.5” drivers are mw-6503. Since even the internal wires appear to not be original, Polk used Solid white and solid black wire inside!  

 

barry

Hey it’s a project, when I did mine, I put new gasket material around all drivers, dynamat on mid woofers and passive radiators too.  But I tend to overdo things.  I even put black hole material behind mid woofers and tweeters in my SDAs, and my SDA inductor was a special toroidal one   ordered from Jantzen.

Edited May 15, 2020 by BarryG

[BarryG 2,853]

A hot air gun is useful to soften the glue!

[RodH 4,866]

EW!!!

 

 

If I make you new crossovers will you burn those?

 

Yes, I'm serious.

[Sk1Bum 11,403]

fsck / 

 

Now I'm really confused.

 

This may be what I need:

 

ebay

 

 

 

 

1 minute ago, RodH said:

If I make you new crossovers will you burn those?

 

 

Happily. I would even ship one to you so that you could enjoy burning one too!

[RodH 4,866]

I have all the parts in stock.

Would you mind measuring the size of the opening in the back of the speaker so I can fit the proper mount?

[Sk1Bum 11,403]

4.25" or 108mm

 

 

[RodH 4,866]

Those are large.  We need to talk!

[Sk1Bum 11,403]

3 minutes ago, RodH said:

Those are large.  We need to talk!

 

PM sent...

[compwaco 1,129]

I think the crossovers look correct. The Monitor 10's, 10a, 10b & 10c are all different. These are Monitor 10 Series II which are fairly rare. (The last of the Monitor line and somewhat evolved from all of the earlier versions)

[BarryG 2,853]

Thanks rod!  The more I looked at the pics, the more I was shaking my head!

 

you will have great speakers soon sk1bum.

Edited May 16, 2020 by BarryG

[CT-Seven 764]

One thing that would concern me is that the aftermarket tweeter added new holes into the cabinet and would have to be properly sealed before adding the new tweets (but maybe you are aware of this already)

[BarryG 2,853]

5 hours ago, CT-Seven said:

One thing that would concern me is that the aftermarket tweeter added new holes into the cabinet and would have to be properly sealed before adding the new tweets (but maybe you are aware of this already)

Seal as tight as possible, I’d check all gaskets, passive, mid woofers and even the connection cup!  I bought a roll of armacell (tip from Polk forum).  Trim as needed as it’s 2” wide, one roll will last for a lot of speakers!

Edited May 16, 2020 by BarryG

[AndrewJohn 10,451]

Filling superfluous holes in cabinets that needed sealed (or stripped out screw holes from replacing drivers too many times...) I have found the following trick to work well.

 

Back in high school wood shop, Mr. Setzer, my teacher taught us to make our own wood putty from fine sawdust of the same wood, mixed with wood glue to a paste, then put glue in the hole, and use a tooth pick and other push-tools, to cram the putty in the hole.  Once dried, re-drill the new hole (if it's to be in the same place) or smooth over with light sandpaper.  On fine furniture, often with stain, you can't even see the patch..., for this application, the glue-putty is actually as strong as the original wood.  If it's in MDF, it's stronger!

 

Using today's Gorilla Glue, that expands, you can use this technique and really create a seal to the box...

 

Those are going to be nice once you restore them.  Can't wait to hear your impressions.

[Sk1Bum 11,403]

When I ordered the PD0198s, I asked about gaskets for them. The salesperson told me they don't sell gaskets, but they use Freezer King 1/8" adhesive backed gasket material to make their gaskets. I found a roll of that at my local Ace hardware for under $4.

 

The holes from the Vifa tweeters will be underneath the new tweeters, so cosmetics aren't much of an issue to me. I just don't want the patches to be as ugly as those crossovers.

[Sk1Bum 11,403]

19 hours ago, BarryG said:

Might not hurt to double check that the 6.5” drivers are mw-6503.

 

They are. I found one of the screw holes is stripped out, so I'll use AJ's tip to refill the screw hole. 

[RodH 4,866]

Ready to ship out:

 

[Sk1Bum 11,403]

Awesome!

[PMAT 2,038]

Very pretty!