Monitor 7's and 7A's

[NeilGabriel]

Hey...I've read some threads on differences in the various Monitor 7's and thought I would toss this in. Hopefully, the pics will attach. I have a pair of 7's (dark imitation wood). I am guessing the 7 has the SL-2000? Pic attached hopefully. Maybe it was the care they got, but they appear to be much newer than the 7A's that arrived fed ex today(more redish imitation wood). The 7 grills hold on with pegs and the binding posts are below center. The 7A's maybe have the Peerless (though it appears to be modified)(see pic). Any thoughts on this? All black with pin hole in center. The 7A grills are held with the first generation velcro (boy, don't like that stuff). The binding posts are above center. The 7A's have double fuses and the 7's have none. From a quick attempt to do an A-B, the 7's sound better to my ear in mid range area. When compared with my 10B's, I know why I plan to be buried with the 10B's. The mids on 7A also have a 1/4 inch cardboard ring around the outer edge of the speaker, and 7 does not. OK...wake up now. Neil (first two pics on left are 7's and next 3 are 7A's)

[adam2434]

The ones with the silver coil tweeters (SL-2000) look to be 7C's, which are the 2nd last series of the old style Monitor line. Probably made around '85-'90.

[mhardy6647]

The original Model 7 (which was never called "Monitor 7" AFAIK by Polk) used the Peerless KO10DT silk dome tweeter and an uncoated, 8-inch passive radiator. The 7A had a 10" coated PR.

I do not know if the crossovers differed or not.

Hope this helps.

Original 7 and 10:
http://img.photobucket.com/albums/v223/mhardy6647/earlypolkfamilyportrait.jpg

A 7A (one of mine):
http://img.photobucket.com/albums/v223/mhardy6647/Polkmonitor7Asn4900.jpg

[NeilGabriel]

Mhardy...your 7A looks identical to mine. So what tweeter do we have? It would make sense that my so-called 7's are 7C's as they do not appear all that old, but I really do like the sound. Thanks guys. (Oh, the so-called 7's also have the Polk "professional" label at top right on rear of speaker, whereas 7A has what you see in pic.) What were years of production on 7A if you know? All of this probably doesn't matter, but it is nice to know what to call the children!

[NeilGabriel]

Sorry...what's the difference in fusing? My 10B's have single fuse and I've seen 10's without. The 7A's I just got are double fused (one for tweet and one for mid??). Curious why some have and some don't. Thanks....Neil

[mhardy6647]

The 7A's have the Peerless silk dome tweeter with the Polk-supplied hole in the middle :-) I can only tell you that I bought my 7A's in 1978 as floor demo units from Soundscape in Baltimore. They continue to serve me well.

At least some 7A's had two fuses (a tweeter fuse and a system fuse). Mine have two fuses, but I have read here that some 7A's had only the tweeter fuse.

http://img.photobucket.com/albums/v223/mhardy6647/7Atweetwoofsn4900.jpg


Bonus, completely gratuitous, Peerless photo-op: Here's an OEM Peerless KO10DT in a rather surprising place (i.e., it surprised me!) -- an early version of the Teledyne-era Acoustic Research AR-14 two way acoustic suspension speaker. I have one :-P of these...
http://img.photobucket.com/albums/v223/mhardy6647/oldAR14tweeter.jpg
Note the lack of the center hole and the weird escutcheon on the version of the tweeter AR used.


AR used a different tweeter in later AR-14's (at least I have a pair of this version!):
http://img.photobucket.com/albums/v223/mhardy6647/AR14tweeter.jpg