Please review my plans to recap Polk Monitor 5s

[KenAnderson]

Hi all.

I obtained my Monitor 5s free a couple of months ago, and they don't sound as good as I'd like, so it's recap time. I've already replaced the external fuses, and that helped big time.

I have no soldering experience, and nowhere near the electronics knowledge that I'd like to have, but this really doesn't look too hard. To practise my soldering skills, I unsoldered tiny resistors and caps in a radio I picked up at the dump, and then soldered them back in. I'm feeling confident about being able to do the larger components that I think I need for this project.

I've read a bunch of posts in this forum, and think I know what I need to do, but I'd really appreciate it if one or more of you would just have a look at my plans and let me know if I'm good to go, or if I need to make changes, or if you think I should choose other parts.

I've attached a pic of the crossover below.

As near as I can tell, I have the following parts.

• 12uf at 50vac electrolytic capacitor
• 34uf at 50vac electrolytic capacitor
• 6.2 ohm resistor at 5w
• 2.7 ohm resistor at 5w

I plan to replace these with one of the following configurations. One config is considerably more expensive than the other.
Expensive

• Sonicraft GEN I 12uf Capacitor, from Sonic Craft, 28.46 USD each
• Sonicap Gen I 34 uF 200VDC, rom Sonic Craft, 62.01 USD each
• Mills Resistor 6.2 ohm 5 watt MRA-5, from Sonic Craft, 4.60 USD each
• Vishay Mills Resistor 2.7 ohm 5 watt MRA-5, from Sonic Craft, 3.95 USD each

Sonic Craft shipping 24.12 USD

Total price for two of each component plus shipping to Victoria, B.C., 295.47 CAD!

Cheaper

• Clarity PX 12uF 250VDC, from Meniscus, 9.40 USD each
• Jantzen Audio 33uF 400V Crosscap Capacitor, from Parts Express, 13.54 USD each
• Mills Resistor 6.2 ohm 5 watt MRA-5, from Sonic Craft, 4.60 USD each
• Vishay Mills Resistor 2.7 ohm 5 watt MRA-5, from Sonic Craft, 3.95 USD each

Meniscus shipping 12.25 USD
Parts Express shipping 31.31 USD
Sonic Craft shipping 14.93 USD
Sonic Craft handling 10.00 USD

Total price for two of each component plus shipping and handling to Victoria, B.C., 174.06 CAD.

I think I'll go the cheaper route, and save myself $125 CAD.

I understand that I should also get replacement standoffs, in case the existing ones don't survive my work. Where do I go to get these?

And, lastly, the existing caps are rated at 50VAC. Replacements are VDC caps. Will that cause me any problems? If "yes", what do I do to deal with those problems?

Thanks,
-Ken

 

[rayma]

No problem with the voltage ratings. Sure the new caps and resistors will fit?
For similar standoffs, look for Panduit in Digikey, Mouser, etc.

 

[Inductor]

Caps: Vac and Vdc is (almost) the same thing except, for the same cap "Vac" is higher because it doesn't heat up so much the capacitor.

 

[Lojzek]

You can do better if you look long enough!

Because the order is still below minimum amount, you have all sorts of gadgets to choose from to modify speakers even further, and you could exchange the inductors as well.

 

[tuantran]

PCX INDEX
Hi KenAnderson, please check partsconnexion in Toronto to see if you can find any good component. Cheers!

 

[PeteMcK]

no need to replace the resistors; the main difference between cheap and expensive caps is marketing...

 

[Lojzek]

Seems like OP does not appreciate that kind of comments. Perhaps this thread is all about marketing.

 

[tuantran]

when i see the photo i guess that the original capacitors are the film capacitors

 

[tuantran]

I have the list of components from Parts Connexion for upgrading the crossovers
Clarity Cap PX 12uF 250V 9.34 X 6 = 56.04 CAD
Clarity Cap PX 10uF 250V 8.06 x 2 = 16.12 CAD
Mills resistor 12W 6.2 Ohm 7.42 x 2 = 14.84 CAD
Mills resistor 12W 2.7 Ohm 7.42 x 2 = 14.84 CAD
Total is 101.84 CAD plus shipping and handling.
I don't have experience with Clarity Cap PX 250V but i have used Clacity Cap ESA 250V and i like it but ESA 250V capacitor is more expensive. Hope this will help to improve the sound of your speakers. Cheers!

 

[eriksquires]

Check the ESR of the big electrolytics before replacing.