OG Monitor 7 upgrades
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dyche01
Posts: 8
I recently joined the Polk Monitor 7 club (cult?), when I picked up an inexpensive pair at the local electronics exchange. After playing my old Marantz receiver though them a few times I realized what all the fuss is about.
I posted about them over in the Audiokarma forum and got some good advice about upgrading them. Based on: (1) the uncoated paper cone in the radiator; (2) grill attachments; and (3) the hard-mounted crossovers, they appear to be the very first series of Monitor 7's. They also have low, consecutive serial numbers (1255 and 1256). The best guess was 1976.
When I went to damp the baskets and upgrade the crossovers I discovered that the drivers had been sealed into the cabinet with moretite putty (further evidence of their great age). The crossovers themselves were mounted on mdf perfboard and put together in a charmingly haphazard manner. After doing the modifications and sealing up the cabinets they sound even sweeter than I could have imagined.
I posted about them over in the Audiokarma forum and got some good advice about upgrading them. Based on: (1) the uncoated paper cone in the radiator; (2) grill attachments; and (3) the hard-mounted crossovers, they appear to be the very first series of Monitor 7's. They also have low, consecutive serial numbers (1255 and 1256). The best guess was 1976.
When I went to damp the baskets and upgrade the crossovers I discovered that the drivers had been sealed into the cabinet with moretite putty (further evidence of their great age). The crossovers themselves were mounted on mdf perfboard and put together in a charmingly haphazard manner. After doing the modifications and sealing up the cabinets they sound even sweeter than I could have imagined.
Comments
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From all these clues, can anyone give me a more accurate idea of their vintage? I feel like I am working on a handcrafted product. Does anybody know many people were putting these speakers together in the early days.
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Just procured a '74~'75 set of 7's. Legend has it that they were hand built by Matt Polk and the early crew of minions. So you might have one of the early runs built by the original crew.
Still love the sound of them. Easy on the ears and smooth as silk.
Nice grab on the pair! Rock on!
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What camera are you using?
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Those are awesome ! Good to see you (or someone ) epoxied those shifter magnets. I took my monitor 5s apart to do some crossover upgrades and the simple act of sitting them down on the workbench shifted a magnet. I made a jig and fixed the original speaker.
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Thanks for the comments!
I suspected that these might have been hand-built in the early days. I am blown away by how tight and clear they sound, especially with acoustic instruments and female vocals.
The camera is an Olympus micro-4/3 body (PEN-1) with an amazing old Konica SLR lens from the 1980s (57 mm f1.2). It is sharp and fast and has great bokeh.
And, based on pro-tips from another forum, the first thing I did when I opened the cabinets was to epoxy the magnets with JB Weld. I am really impressed that you were able to reseat a shifted magnet! -
they are really snice speakers .
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Very nice! I had a similar pair and loved them. They do a lot right for a budget speaker.
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Thanks for the comments!
I suspected that these might have been hand-built in the early days. I am blown away by how tight and clear they sound, especially with acoustic instruments and female vocals.
The camera is an Olympus micro-4/3 body (PEN-1) with an amazing old Konica SLR lens from the 1980s (57 mm f1.2). It is sharp and fast and has great bokeh.
And, based on pro-tips from another forum, the first thing I did when I opened the cabinets was to epoxy the magnets with JB Weld. I am really impressed that you were able to reseat a shifted magnet!
Kind of amazing how little it took to shift that magnet. I was very careful best i recall. The magnet is fixed as good as new. I have listened closely and there is no problem whatsoever with the repair. And as was stated above they are very nice even though they are not 7s.I put some Clarity PX series (12uF) in the tweeter side of the crossover and left the rest as is (for now) however i am not sure if i should mess with them any more as they sound fantastic as they are. -
I just bought some old 7's; how do I epoxy the magnets? Just run a bead around the top (exposed) edge where the ceramic magnet meets the steel frame? Thanks.When freedom is outlawed, only outlaws are free...
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Yep, that's it!
my 3.1TLs
I will fix your shifted magnets for free.
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You need to apply a bead around the top and bottom. Loctite Power Grab is a lot easier to work with.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
I just bought some old 7's; how do I epoxy the magnets? Just run a bead around the top (exposed) edge where the ceramic magnet meets the steel frame? Thanks.You need to apply a bead around the top and bottom. Loctite Power Grab is a lot easier to work with.
This thread has good info and pictures.
http://forum.polkaudio.com/discussion/171529/polk-10b-monitors-crossovers-and-tweeter-upgrades
