Crossover component upgrade

Dasouthwon

I have seen several people on different forums mention upgrading the components in the crossovers of their speakers to get a cleaner sound. Has anyone here done this, where did you get the parts, and was there any real audible difference. I have the skills necessary to do it but am not sure exactly what to improve or replace. For instance what is the best kind of capacitor for SQ, and are there some brands that are better than others? Thanks for the help. Brian

F1nut

Click on the "Tags" button, type in crossover and you'll get more hits than you might care to.

Dasouthwon

I did a search prior to making the post. I'll try the tags function to see if i can come up with some better answers to my question. Thanks

F1nut

This should get you started.

http://www.polkaudio.com/forums/tags.php?tag=crossover+upgrades

Dasouthwon

I pulled the back plates off of the Monitor 30's I have to see what was inside. I found that the crossover has 2 capacitors. One has a value of of 8µ0, 50v, NP105C. I'm unsure what the 0 in the 8µ0 stands for. Im guessing the NP105c means non-polarized, 105 degrees celsius. The other capacitor has a value of 18µF, 50v, NP85c. I checked the Sonicaps site and couldn't locate an exact match for these capacitors. The closest thing I could find was one with a rating of 8.2µF / 200VDC, the other has a value of 17µF / 200VDC. Which is .2µF to high on one and 1µF to low on the other one. How important is it that the replacement capacitors match the value of whats being replaced, and if I were to replace these caps would I notice much of a difference in these entry level speakers?

ben62670

Don't get hung up on the voltage rating it means nothing pertaining to XO caps;) New caps will be much better than the stock caps.
Ben

Early B.

Don't waste your time upgrading the Monitor 30's with Sonicaps.

Dasouthwon

After reading, I see that you can match the farad load by wiring capacitors, with values that total the stock rating, in paralell. So the voltage rating is irrelevant, those are the things I'm trying to find out.

Is there any benefit from replacing the coils and ceramic resistors?

I guess what's driving the speakers is important. My reciever is a Denon AVR-888. I have a Carver AV-505 that I'm currently not using since the Denon doesn't have pre-amp outs. I thought about listing it on here for trade, just no idea what it's worth. I'd like to get some better mains. I've been peeking at the LSi series (kinda expensive for me).

Thanks Earl for giving me the straight up on the monitor 30's. I kinda figured it would be pointless to put $150 worth of capacitors in $150 speakers. It's more the learning curve I'm after.

F1nut

I certainly wouldn't say the voltage values don't matter, they do. As long as they are equal to or greater than the original values you're good to go.

Where did you get $150.00 from? Using a total of two 8.2uF for the 8uF's and four 8.2uF's for the 16uF's with the 20% off sale going on right now comes to a grand total of $78.24. Add some Mills resistors few a few more bucks and your speakers will definitely sound better.

Leave the inductors alone.

Dasouthwon

I may just do it for s&g's, what is the maroon porcelin transistor on the board? It's the only other component besides the caps, coils, and resistors?

Do certain Farad values determine the crossover frequency or is this controlled by the inductors?

Dasouthwon

I was trying to send them an email to order the caps and resistors, but I'm not sure what the value of the resistors is. They are the white rectangle ceramic type, on the side of one it says 5W1R8J and the other says 5W5R7J. Every mod that I've seen has left these style resistors alone. Is there a benefit to upgrading them?

F1nut

Do certain Farad values determine the crossover frequency or is this controlled by the inductors?

Both.

maroon porcelin transistor

Can you post a pic of that?

on the side of one it says 5W1R8J and the other says 5W5R7J.

1.8 ohm, 5 watt and 5.7 ohm, 5watt

Every mod that I've seen has left these style resistors alone.

I'm not sure what mods you've seen, but it is probably because the ones you saw had resistor wattages to large to replace with Mills, which only come in 5 and 12 watt. Changing the resistors to Mills, if possible, will yield excellent results and I highly recommend it. When you consider that a 12 watt Mills cost $3.85, there's no reason not to upgrade to them.