Finally made a step into Vintage Polks for me

michael_w

So today I picked up my first set of vintage polk audio speakers. I bought a set of Monitor 7Bs off a person for $100 cdn. They are in mint shape acoustically but the cabinets and grilles a little beat up. The veneer has some scratches and the grilles have been subjected to the mercy of a cat :mad: .... they are pretty frayed around the edges and a bit dirty but hey I like the looks of them way better with no grills for a change.

They are a lot brighter than I was expecting and am used to (first time actually turning down the treble instead of leaving it flat). The soundstage on these speakers is huge and they seem to dissapear quite nicely. At the moment I still enjoy my LSI 7s a bit better but these are damn nice considering what I paid for them and I will definatly be keeping these for a while.

No stands yet so they are tilted upwards a little with books in an attempt to allign the drivers or somethin lol...

Anyways I need to stop writing and get back to some listening Here are some pics.

Skynut

They look sweet. The grills really should not be too bad to fix.

I have the same problem with the highs on my system, I like bass and have to turn the treb. down a bit.

Congrats, I hope you like them.

michael_w

Yea the grill cloth just needs to be replaced and that would be easy if I can find some decent stuff (preferbly in Canada... I know PE carries it but I hate duties and that stuff).

I found a minor problem... when they are playing loudly the back panel of the right speaker vibrates as if a little loose. If I put my hand against it it stops.

I really like the looks of them. They are so clean being all black with dark veneer and that kind of brushed steel looking tweeter... hehehe ***back to listening***

RuSsMaN

Buy the Polk Silk Dome replacement tweeters, and get your listen on.

Search on the proper stand, Mark (Dorokusai) made a thread with the correct diminsions / angle.

Cheers,
Russ

danger boy

cool... i also see some Athenas in there.. and the LSi 9's. what else you hoarding in that room?

kind of strange.. but i wonder why your 7B's. and my 7B's. look so different? mine has all cloth grille fronts.. and yours shows some wood on the bottom.. with the Polk logo attached to the wood. the logo on mine is on the cloth grille. strange how both are Monitor 7B's. yours are darker color vinyl too.

I think they LSi's might be more laid back.. with that Vifa tweeter.. maybe that's why the 7B's. seem bright. Mine don't seem to be bright to me.. what kind of interconnects are you using? Speaker wires?

Tour2ma

Looks like the SL1000 had its high-beams on in that naked pic...

I guess the SL2000's replacement, the RD0194, also replaces the 1000.

As for the loose back panel, you may find that that cabinet is not sealed tightly. Try pushing (firmly, but gently) in on its PR and hold it in. Watch the MW as you do this.

The MW should move outward and hold or very slowly retreat back to its start position. If it pushes out and quickly returns, bad seal. Do the same with the other speaker for comparison.

Pulling the PR will give you the access you need to reseal the back panel.

Once resealed, and the tweeters are replaced, I think your pecking order will change.

michael_w

Turns out that they are Monitor 7Cs... wierd cause the original serial number says 7B but is scribbled out and writeen in pen that it is a C...

Turns out the seal is good on the left speaker but the MW does slowly move back in when I lightly push in the PR. So once I'm inside (through the pr) how can I get the cabinet to seal again? I have no idea what the internal structures are like in these cabinets. Would it just be a gasket thing or some caulking? I'd rather not take them apart till I know what I'm doin because then I can listen to them until then

Russ I was looking at Marks thread about stands before I bought them and it should be simple enough to make (dads a cabinet maker so if I need help no prob ). I found this page but I don't see RD0194 on the list.. I'm not so sure I want to drop more cash into these speakers just yet since I also bought an Atlas 15 today and am seriously thinking about quitting my job for many many reasons but that's a whole different issue. What do the silks go for?

Tour2ma

I think the tweets run ~$45/ ea shipped to Club Members (we get discount and free shipping). The parts list does not reference the new replacments, just the original model numbers.

Silicon caulk would work. On the loose side I might go with a bead of hot glue first (a little better penetration of the joint), but I'd probably silicon over that once the glue has set.

michael_w

ok... I've never done this before so is there silicone caulking specific to wood or is it kind of universal stuff? Maybe my dad has some in his shop.

Heres a pic of the messed up serial number... by looking at other pics of 7Cs I'm pretty sure it is a C not a B but why would it be printed as a B but maybe changed to C at the factory or something?

michael_w

Mad Max,

My room is packed with stuff lol... It's built around my audio stuff with my computer on the side, recliner in the middle and bed above the audio video stuff. The room is a tiny 8" by 13"... I'm using an NAD C352 integrated amplifier, tosh sd-3800 cdp, kimber heros, acoustic research bananas on the speaker ends and some home depot special 12 awg speaker wire (as seen in this pic) and an athena sub 8 sneakly sitting in the left corner there - soon to be replaced by a massive atlas 15 - for my 2 ch stuff. Also no 16 year olds room is complete without a black bar fridge

danger boy

michael_w

nice set up you've put together. be proud of it... and rock on :cool:

michael_w

Thanks. Yea I havn't been in this hobby for too long but I'm really enjoying it. I listen to my 2 ch system whenever I'm in my room and I find it's awesome for just relaxing from the stresses of going to school and working 25-30 hours a week.

Tour look what I found in my dad's shop..

it says it's good for glass, metal, wood, plastic, rubber etc... and is water and weatherproof for use indoor and out. This will work right?

michael_w

So I pulled off the pr and this is what I find.



Is it necessary to keep the polyfill in the same folded pattern/ shape it is before I take it out?

edit: nvm I just pulled it out and it's just like a blanket folded and rolled like a cinnamon bun .... mmm I think its lunch time

Loud & Clear

That's the SL1000, so replacing them won't be easy unless the faceplates of the SL1000's were made larger for the Monitors. Measure the faceplates, if they're 4 1/2" x 3" you might be keeping them stock.

michael_w

yea the faceplates are 4 and a half by 3" ...

Well I just finished caulking the back seams. First time using caulk and I must say that I did a pretty bad job ... Hopefully it works but damn it sure isn't a pretty bead . Pretty hard to get it all smooth doin it through the pr hole. Those fumes are crazy... its like burny vapororized vinegar. How long should I wait before I put the PR back on and let er rip?

ok it's terrible but heres a pic...


pic might not work just yet (website keeps crashing today)

nadams

BTW- you'll probably never get a perfect seal. On my monitor 10's, when you push in on the PR, the drivers will come out, then slowly fade back in.

michael_w

I'm not looking for a perfect seal (although that would be ideal) I am just trying to get rid of the massive rattle when it is playing at moderate to high volumes.

michael_w

YAY!! The caulking worked perfectly... no more rattle and when I push the PR in the MW takes a long time to move in again. So it still isn't a perfect seal but it's damn close.

My dad suggested that I do the other cabinet as well just to balance things out and if the one un-sealed itself it's only a matter of time that the other one does it too. I'm going to put that off for a bit and focus on making a box for my Atlas 15 that should be shipped from Ascendant Audio sometime next week.

Just too bad I have to work all day tomorrow cause I just wanna sit and listen

BobMcG

There seems to have been a transitional faze in the change-over from the 7B to the 7C. (Not that we haven't noticed that within the Polk lines before.) While my Mon 7s have the Polk badge on the exposed wooden section at the bottom of the speaker rather than on the grill, they are clearly labled 7B and have the soft, black, dimpled Peerless tweeters.

danger boy

there were probably lots of similar changes within the (original) monitor line of speakers.... slight changes like the grille and where the logo badge was placed.. and of course different tweeters were also used.

something you don't see today.. so those older Polks are somewhat unique.

PolkFreak

I think someone who thought they knew better decided to put the, "C" on there. They are the Monitor 7B. They might have come out with one that didn't have the fuse protection too. For Example, somewhere before 1985 they had the old fuse crossovers on the Monitor 10B which at the time had older drivers as well which were the MW6501. They even had the SL1000 tweeter. Then, sometime after 1985 hit they used a polyswitch for tweeter protection which got rid of the old and ugly (IMO) fuse on the back of the crossovers. They then upgraded both the drivers and tweeters and still called it the Monitor 10B. The mid/bass drivers where the MW6503 and the tweeters were the SL2000. I used to own a real pair of Monitor 7C's which I sold to my brother. They don't have a fuse on the back of the crosssover. They also DON'T have the SL1000 tweeter that the speaker in the picture has. The Monitor 7C's use the SL2000 tweeter and the MW6502 driver. Mine were 1985. I've read a lot of the old polk books that have all of the info. Click on this link and it will show a list of different models. Between reading those old Polk magazines and buying so many of them as well reading the parts lists and comparing info I know the vintage Polk line pretty well. Oh ya, here is that link: http://clubpolk.polkaudio.com/service/models/modelpartslist.php3?model=monitor Be careful because not all of the info in the vintage section with pictures and other info is correct. They have a bunch of Polks that are rated at 4 ohm incorrectly rated at 8 ohm. One of the only speakers that is NOT 4 ohm is the Monitor 10 which is 6 ohm. My Monitor 7C's were rated at 4 ohm, but some 1970's models of the model 7 are rated at 6 ohm. They do have a listing for a Monitor 7C with and SL1000 tweeter, but they also list the crossovers as being exactly the same which is impossible because the tweeters are different and so are the crossovers. One has a fuse and the other does not.

michael_w

Interesting... So I have pre 1985 Monitor 7Bs then? It's too bad that polk hasn't better documented all these little changes that make their vintage speakers so unique.

PolkFreak

Yup pre 1985. You can find out the exact date if you are willing to open them up and see the date stamped on one of the drivers. It is hard to say the exact time when they made changes. For example, the year they made a change could have old models dated the same year as the newer ones. The Monitor 7C was my first vintage Polk speaker. The depth of sound that comes out of those things is awesome IMO. Anyone who has the pleasure of owning a pair of Monitor 7's is lucky. I'm happy that another person has discovered the unique quality that the vintage Polk speakers have. I mean to say I'm just plain happy for ya:D
Happy listening!

GrahamT

I'm the original owner of a pair of Polk 7C's purchased early '85. Note the SL1000, fuse, and original 7C serial number. So maybe michael_w's B was legitimately changed to a C if the factory used up their old supply of serial number tags!

The 7C's were purchased as second room extensions substituting for an even older, larger and more expensive pair of Infinity Column II's. The 7C's were the only speakers I didn't mind listening too in place of the Column II's. Both sets of speakers are still in service, the Infinity woofers (all four) have had their surrounds replaced.

July 4th, disaster strikes. A "friend" cranks up Neil Diamond to entertain the neighborhood. Before I can reach the volume control, a cone is damaged, the driver coil driven off-axis and the result is permanent contact with the magnet.

Thinking I might stumble on some salvaged parts I start looking on the internet and stumble across ClubPolk. I can't believe my eyes; MW 6502 drivers listed. A quick phone call and I have a replacement driver shipped free at a reasonable price for a 20 year old loudspeaker. Way to go Polk! I'm impressed, very impressed and will happily pass the word on the great service.

Better yet, the friend, who was out of favor for a few days, is a friend again!

The forensic speaker historians among you trying to figure out 7B's vs C's, might be interested to see the driver that was replaced. Stamped "101084" "WARRANTY NOT FOR RESALE" and in fine print "Warranty use only Nov 20 84." Maybe my speakers weren't quite as new as I thought they were when I purchased them from the dealer - but after 20 years of great service, I'm not complaining!

F1nut

Good story Graham and welcome to the forum.

If you spray some Windex on a lint free cloth and gently wipe the rubber surround on the PR in a circular pattern, it will remove the "brown" oxidation.

VR3

I hope you didnt put those drivers back in there right after you applied the caulk

*SMACK*

Caulk contains ACIDS, and it will eat away the parts of that driver...

Open that speaker back up someday, it will smell SO bad.

PS: it takes caulk about 2 weeks to fully dry.

michael_w

I did put it back on after about 3 hours and the day after thought to myself that since those fumes were so crazy maybe they arn't so great for the drivers. I let it air out a bit before putting it back together.