Monitor 10 crossover upgrade

RobertRS

I have a pair of Monitor 10 (not b or revised) that I have ordered RDO 194-1 tweeters for them and want to upgrade the crossovers. Polk customer service said I have the SL 2000 tweeter. The crossovers have the external fuse so that means no polyswitch?

I have two 2.7 ohm resistors and a 34 uf and a 12 uf in one crossover.

Some of the threads I have read call for 2-12 uf caps each, a 34 uf cap and a 2.5 and 2.7 ohm resistor.

Sonicaps caps and Mills resistors have been mentioned as the way to go.

Can someone shed some light on the crossovers for me, are mine earlier?

Nightfall

Can you post a picture of your Monitor 10's with their grills off?

Faustin

Something does not sound right if your c/o only has 2 caps. Should be a 34 and
2) 12's. As Nightfall suggested post a picture of the speaker so we can see all the drivers and if you have the c/o out of the cabinet post a couple of pictures of that as well. Under the Vintage Speakers forum you will find schematics to use as reference.

pitdogg2

get a look at both XO's and then get what you need from what was originally installed. Clarity cap is another as well as Mundorf resistors. Either company has good results here tried and true.

RobertRS

Thank you for the fast comments.

Speaker ser number 60515 has only one 12 uf cap has 2-2.7 resistors
Speaker ser number 64497 has 2-12 uf caps and 2.5 and 2.7 ohm resisitors
Black dome, oblong tweeter, no marking on back just round magnet
Both have 34 uf caps, both have external fuses

First I thought the cap had fallen into the cabinet, after I looked at the second crossover and see how cap is soldered to the resistor there is no evidence on the second 12 uf cap.

Not sure how to upload photo to this forum.

Nightfall

I believe you have Peerless tweeters, the RDO-194's are NOT a replacement for them nor will they even fit without modifying your cabinet.

Upload your photo to https://imgur.com/ then copy the "direct link" and paste it in a post here.

RobertRS

Should have said rectangular black face plate and black soft dome tweeter

Nightfall

When did you order the tweeters? Perhaps it's not too late to cancel your order. If you can figure out how to post a picture someone will be able to tell you for sure.

Nightfall

RobertRS wrote: »

Should have said rectangular black face plate and black soft dome tweeter

My statement stands. Does the dome have a small hole in the center?

pitdogg2

you have monitor 10 original with peerless tweeter made in Denmark...Polk doesn't have a substitute like the SL2000 to RDO-194

but it is strange they are so different....do they sound different?

Nightfall

If you need/want to replace your tweeters, this is the only new option.

https://www.midwestspeakerrepair.com/mw-audio-mt-4115-1-inch-dome-tweeter

RobertRS

The speakers are at the far end of my garage so not critical listening just background music.

RobertRS

Nightfall my tweeters look just like those you sent the link for.

My tweeters work, I just got caught up in the upgrade mode, thought if there was something better why not.

Yes there is a hole in the center of the dome.

Nightfall

The RDO-194's will not only not work correctly with your crossover they won't fit.

RobertRS

Nightfall so my crossover choke values are different? My crossovers look like the ones folks have posted photos of.

Lots of suggestions to replace existing tweeters to RDI 194-1 but if I have Peerless guess I am out of luck.

Nightfall

Rest assured that you have fine sounding tweeters already. Call Polk back and see if you can work something about about either cancelling your order or returning them after you get them.

RobertRS

To all thanks, I was able to cancel my order for the tweeters at Polk I had just ordered them two hours ago, guess I will just recap and re resistor my crossovers.

Nightfall

Some pictures of everything, including the crossovers, would likely help the crossover gurus help you out.

I have to question upgrading the crossovers on a pair of garage speakers though. What are you using inside your house?

RobertRS

So no reason I should not recap and reresistor? I will go with 2-12 uf, 34 uf, 2.5 and 2.7 ohm resistors

Nightfall why did you say the 194 would not work with my crossover? I know it will not fit my cabinet but I thought the crossovers were the same?

RobertRS

I recently recapped some Advent (original, large) and some AR 4 xa speakers and was surprised at the improvement in sound,

I have some home built speakers, am currently building Onkens which are based on Altec A-7 speakers, building them for low powered tube stuff. Also have a pair of KEF LS-50 speakers.

pitdogg2

how long have you had the Polk Monitor 10's ? are you the original owner? better post pictures of XO's and Front of speaker.... could be that they may of came with SL2000 and someone switched them out for the peerless as most really liked those.

Nightfall

pitdogg2 wrote: »

could be that they may of came with SL2000 and someone switched them out for the peerless as most really liked those.

This is what I was thinking too.

If that is the case, you can go ahead and order the RDO-194's again. Some pictures will really help, including the crossovers.

There is nothing wrong with upgrading the caps in your speakers. I was just curious why you would spend the money to do that on a pair of garage speakers that are only for background listening, as you said, instead of upgrading what you have in your home for critical listening and enjoyment.

RobertRS

The Polk customer service folks ask if I had external fuses (yes), ask if it was a black rectangular tweeter (yes), then said you have the Peerless tweeter and that they sound good. He could not explain why the crossovers were different. Added the serial number was of no help that they did not keep that info.

Nightfall

@westmassguy Are you familiar with the differences in Monitor 10 crossovers? David might be able to help you out Robert.

RobertRS

I got these from a friend when he upgraded to a flat screen TV and his wife wanted smaller speakers in the living room. I believe he is the original owner.

westmassguy

Unfortunately we don't have schematics for the 1st Monitor 10s. If you can, post some photos of the front of the speaker, and the crossovers. The crossovers should match.

RobertRS

I found a crossover drawing dated 11/26/84 called Model 10 which shows the 1A fast blo fuse, so it seems correct. My speakers say Model 10 on the paper label on the back. I can't measure the inductors but the values for caps and resistors is correct for one of my crossovers, the other is missing one 12 uf cap and both resistors are labeled 2.7 ohm but they could have been hand selected as are 10% tolerance

I can't seem to get the images off my phone to my computer. I once emailed a photo from my phone but that is about all I have ever done, sorry

pitdogg2

Velcro hold grills on? Most likely mw6500 for drivers iirc

RobertRS

No four bumps that go into the grill frame, one at each corner. the baffle board has a black textured surface the bumps are not recessed as I have seen in some photos. The tweeter has a similar black textured surface. I can see quality control labels on the drivers but no part number mostly signatures from different inspections.

RobertRS

There are some Polk crossovers on ebay that are just like one of mine. The pair are both missing the second 12uf cap. My second one has a second cap the lies on top of the two resistors such that you can see both resistors from above. On ebay go to "Polk crossovers" it is the 7 th listing, a pair "monitor 10" crossovers $29.99, buy it now. If you open the listing there are four photos

westmassguy

RobertRS wrote: »

No four bumps that go into the grill frame, one at each corner. the baffle board has a black textured surface the bumps are not recessed as I have seen in some photos. The tweeter has a similar black textured surface. I can see quality control labels on the drivers but no part number mostly signatures from different inspections.

The Peerless tweeters were flat, painted steel, with a black fabric dome. The SL2000s have a raised black plastic bezel and clear/silver colored dome. The RDO-194-1s have a similar raised black plastic bezel, with a black fabric dome. Pictures are worth a thousand words.
These crossovers are most likely what you should have in both cabinets: http://www.ebay.com/itm/Polk-Audio-Monitor-10-Crossovers-/181997832833?hash=item2a5fea8a81:g:K-MAAOSwLnlWn~id

This one appears to be the same as the oddball crossover you have:
http://www.ebay.com/itm/1-VINTAGE-POLK-AUDIO-MODEL-10-SPEAKER-CROSSOVER-2-3-WAY-1978-FIX-REPAIR-PARTS-/331757609886?hash=item4d3e4b639e:g:mMEAAOSwL7VWnaJr

If they were my 10s, I'd go with the later revision, that has the two 12uf caps, and get a pair of RDO-194s.