Old Monitor 5A speakers not working

bobmover

I know this is an old speaker and may not be in the right place. I recently moved and when I went to hook up my speakers (Monitor 5A) very little sound came from them. First I thought it might be the receiver, it's as old as the speakers (31 years). So I replaced it, but no luck, same results: very little sound, it's as if you are hearing the speakers in the background. I love these speakers and have moved them about a dozen times in my life, mostly across country. I am taking the fuses and getting them replaced, but beyond that, I don't know what else might be wrong. Other than taking them apart, what might your suggestion be? The move I did was local and as far as I know the speakers were not dropped. It just seems strange that both of them would not work.
Any help would be appreciated.

Thanks,

Bob

cnh

Welcome to Club Polk!

Certainly check your fuses. You're getting NO sound at all, nothing? No highs, no lows?

Normally when you lose the mids and bass it's usually because the magnets on the mid-drivers have either fallen off or shifted. One way to check for that is to push those drivers in and see if they "seem" frozen, i.e., don't push in or recover their original position.

You can fix that be replacing the drivers. But if your highs are also out. Those fuses must be shot!

Hopefully some of our DIY guys will chime in here. Because those guys can "Fix" anything!

BTW, I have a set of 5As as well, one of my favorite vintage bookies. They're a nice speaker!


cnh

bobmover

cnh, thanks for the quick reply and advice. Put in new fuses and did not cure the problem. There is sound coming out but it is minimal, almost like hearing them in the backgound, with zero bass. I will pop the apart next and try the driver test you suggested next. hard to believe that both of them went at the same time. Maybe the mover dropped them, but there does not seem to be anything loose. too bad, I really loved those speakers. So does my son, who is looking to inherit them one day.

VR3

My guess is a blown inductor or a frozen woofer

Joe08867

I would bet a frozen MidWoofer, Moving speakers of this vintage takes a ton of car as the magnets can shift and pinch the voice coil. If your magnet shifted you will need to get a new driver. Luckily Polk still sells replacements or you can try to find a match on ebay. Just make sure they are the same model number.
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bobmover

I replaced the fuses, no luck. I took the back where the wire hook and and the fuse is located and looked inside. No "see-able" damage or wires disconnected. I did notice that the lower speaker does not have any wires coming in or out of it. It appears that this speaker never had any. I am assuming this is the bass, the middle one the mid-range and the top one the tweeter. I pulled the front off and hooked the speaker to another receiver. The tweeter is vibrating and making a sound, same with the mid-range. the bass has neither sound nor vibration. There is no magnet on the bass, or any other wires or devices. Going back to my earlier statement on the bass, I am assuming it is designed this way. I know very little about speakers obviously. I am perplexed on what is happening.

bobmover

Thanks, I pulled it apart and the magnet seemed intact. Is that what you mean by frozen? Please excuse my ignorance, I am not an audiophile.

pitdogg2

the bottom is a passive woofer your problem lies in the midwoofer. As others have said the magnet may have shifted. Do you feel any scratching when moving the cone in and out? you may not be able to tell by the eye if the magnet has shifted. It can move as little as 1/16" to foul things up. you need to push the cone in and out. Is it stiff? feel scratchy?

skrol

If you gently and evenly press the mid-woofer, does it move freely with no scraping? If it doesn't then it is frozen. If they are frozen, I believe they are the MW6500 which show up here and on eb fairly often.

bobmover

What great responses. It's wonderful have such good advice. Please help me here. I was able to get the back where the hookup and fuse are off, which left me with little room to maneuver. I don't understand what is meant by moving the cone. I am not sure I can do it from the inside either. I tried to me the speaker from the front, by unscrewing it, but it would not pop out. I did not want to force it and tear the paper on the cone. do you know if Polk glued them in? It sounds like my best bet is to source 2 of these mid-woofers and replace them, it looks like there are only 2 wires to attach. I would like to try pressing the mid-woofer, but fear damaging it. Can anyone be more descriptive in how to do this?
Thanks again for all the comments.

pitdogg2

OK place speaker on flat surface on its back take grill off place hand on middle driver from the FRONT push driver in some release pressure but keep hand on driver ....what do you feel? you seem to be over thinking what we are asking you to do. You cannot do what we are asking from inside the speaker....you are just trying to gently move driver back and forth NOT up and down or side to side just in and out as if it is producing sound.

bobmover

I did this on both middle drivers (each speaker) and neither of them budged. No in or out movement what so ever. It would appear that I need to source new ones.

skrol

Bingo! Where are you located? I have a spare MW6500 but I prefer not to ship it as I believe the magnet is shifted slightly. It scrapes a little if moved with unequal pressure but sounds fine playing music where the pressure is equal. I fear shipping would destroy it.

Check the sticker on magnet of the mid-woofers for the part number. It should be MW-65xx.

bobmover

I did this on both middle drivers (each speaker) and neither of them budged. No in or out movement what so ever. It would appear that I need to source new ones.

bobmover

Stan, the sticker says MW6500. I saw on another post that these can be replaced by MW6503, which the poster said I could get from Polk Audio. I cannot find anywhere on Polk's site where I can order these. Maybe eBay then. I appreciate your offer, but I live in Florida and I need two of them.

skrol

I believe that the 6503 does replace the 6500. Call their customer service to order and they will confirm. They are very nice folks and you will get the best service this way. Mention that you are a Club Polk member and they will give you a nice discount. Last time I checked they were 50% off and free shipping for a total of $48 each. The prices may have changed by now.

Used, the 6500 usually goes for between $20 and $35 but you do take a risk.

Mystery

bobmover wrote: »

I did this on both middle drivers (each speaker) and neither of them budged. No in or out movement what so ever. It would appear that I need to source new ones.

That sucks.
If they don't budge, they are frozen. Few threads talk about fixing the frozen driver but I think it's time to buy replacement.
I've seen frozen drivers where magnet looked perfectly good.
Good luck.

bobmover

OK, now that I know I need these MW6500's can someone please help me spec out a replacement? I saw someone post that the MW6503 would work. Not seeing many of those out there. I see a lot of 6502 and other 65xx, but not sure these would be good. Also, how many ohms is the original? 4 or 8?

bobmover

Stan, you are quickly becoming my new best friend. The major reason I want to get these fixed is my son. He is 23 and loves the old school sound and is a ardent "music-phile". unlike most of the kids his age, he loves classic rock, blues, jam bands and just good music. He has been bugging me for these speakers for years and I would like to one day give them to him. It would break his heart if they did not work anymore. Likely more memories for him of listening to these then me.

skrol

No, the 6502 and other 65xx are spec'd different. You want either the 6500 or the 6503. A word of caution if you get the 6503's. This is simple to do but necessary. Take a razor blade (exacto blade works great) and cut the rubber surround material out of the screw holes. Otherwise when you tighten the screws it will wrinkle the rubber surround and it may detach. There are other threads which warn of this and have pics.

skrol

bobmover wrote: »

Stan, you are quickly becoming my new best friend. The major reason I want to get these fixed is my son. He is 23 and loves the old school sound and is a ardent "music-phile". unlike most of the kids his age, he loves classic rock, blues, jam bands and just good music. He has been bugging me for these speakers for years and I would like to one day give them to him. It would break his heart if they did not work anymore. Likely more memories for him of listening to these then me.

Sounds like you raised him right. The Monitor 5's are perfect for him.

cnh

skrol wrote: »

No, the 6502 and other 65xx are spec'd different. You want either the 6500 or the 6503. A word of caution if you get the 6503's. This is simple to do but necessary. Take a razor blade (exacto blade works great) and cut the rubber surround material out of the screw holes. Otherwise when you tighten the screws it will wrinkle the rubber surround and it may detach. There are other threads which warn of this and have pics.

+1, This is "extremely" important. I had someone screw this replacement on my pair of 5s and I had to jump through a few hoops to fix it.

Your son will enjoy those. And they sound great on vintage gear, if you have some. I currently run mine on an old JVC receiver and they sound much better than they should on that!

cnh

bobmover

How funny, I had my speakers hooked up to my old JVC receiver, which I bought along with the speaker 31 years ago. I originally thought that the receiver went bad, so I bought a new one. Good thing I did not throw it away. Now I can take back the new receiver and use the money for these drivers.

helipilotdoug

Glad you got it figured out. As others have said, Polk Customer Service is great. Tell them what you have, and they will fix you up with the proper drivers. Don't forget to tell them you are a Club Polk member to save some bucks. Those new drivers will last you another 31 years with no problem. :cheesygrin: