Polk Monitor 7 speakers with two different crossovers
KB12
Posts: 6
Hello all,
I have a question about a pair of Monitor 7 speakers I recently picked up at Goodwill. When I purchased them they had frozen woofers (MW6502) and SL-2000 tweeters. I replaced the woofers with ones from a pair of Monitor 4 (also MW6502s) that I had lying around. I replaced the tweeters with RD0194-1 replacements from Midwest Speaker. When I hooked them up the bass does not sound right. Its very boomy and overpowering. I checked the crossovers and each speaker has a different one. Pictures are attached.
Are either one of these correct for my speakers? If not, what should I look for as replacements? Or could I recap them with correct caps? And...Could this be why the speakers are not sounding right?
Thanks for any help you can give!
I have a question about a pair of Monitor 7 speakers I recently picked up at Goodwill. When I purchased them they had frozen woofers (MW6502) and SL-2000 tweeters. I replaced the woofers with ones from a pair of Monitor 4 (also MW6502s) that I had lying around. I replaced the tweeters with RD0194-1 replacements from Midwest Speaker. When I hooked them up the bass does not sound right. Its very boomy and overpowering. I checked the crossovers and each speaker has a different one. Pictures are attached.
Are either one of these correct for my speakers? If not, what should I look for as replacements? Or could I recap them with correct caps? And...Could this be why the speakers are not sounding right?
Thanks for any help you can give!
Comments
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What is the difference? What is it that has you concerned that they are different?
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Definitely hard to tell from the two different angles.
Brian
One-owner Polk Audio RTA 15TL speakers refreshed w/ Sonicap, Vishay/Mills and Cardas components by "pitdogg2," "xschop" billet tweeter plates and BH5 | Stereo REL Acoustics T/5x subwoofers w/ Bassline Blue cables | Rogue Audio Cronus Magnum III integrated tube amp | Technics SL-1210G turntable w/ Ortofon 2M Black LVB 250 MM cart | Sony CDP-508ESD CD player (as a transport) | LampizatOr Baltic 4 tube DAC | Nordost & DH Labs cables/interconnects | APC H15 Power Conditioner | GIK Acoustics room treatments | Degritter RCM -
I only see one crossover from two different angles. That is a Monitor 7 Series II crossover and the RD0194 is the wrong tweeter, as was the SL2000. That one should have a SL2500 or the RD0198 which is the upgrade.George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Onkyo A-8017 integrated
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
There are two images, one of each crossover. The first one has 27 MFD caps and the other has caps that are 8 uf.
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The Monitor 7 Series II has 27uF electrolytic shunt capacitor on the MW low pass circuit, and 8uF electrolytic (parallel with 2.7 Ohm resistor) and 12uF mylar (yellow) in series with tweeter.
It looks like it could be that the crossovers are the same configurations but from different angles. You need to take better photos so we can see all the values
George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Onkyo A-8017 integrated
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
I see “8”s all over the side of that bottom cap in the first pic, just like the one in front in the second one. You’re likely to have different values in the different positions. Better pics would help.
Brian
One-owner Polk Audio RTA 15TL speakers refreshed w/ Sonicap, Vishay/Mills and Cardas components by "pitdogg2," "xschop" billet tweeter plates and BH5 | Stereo REL Acoustics T/5x subwoofers w/ Bassline Blue cables | Rogue Audio Cronus Magnum III integrated tube amp | Technics SL-1210G turntable w/ Ortofon 2M Black LVB 250 MM cart | Sony CDP-508ESD CD player (as a transport) | LampizatOr Baltic 4 tube DAC | Nordost & DH Labs cables/interconnects | APC H15 Power Conditioner | GIK Acoustics room treatments | Degritter RCM -
Here are some better pictures:
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That's beyond bizarre because 5jr+ only had 1 capacitor (in series with tweeter). It didn't have 3 capacitors.
Your one speaker may have been hacked and someone put the large inductor for the 5jr+ in there with the rest of the crossover for the M7 Series II. That's a new one!George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Onkyo A-8017 integrated
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
Ok it looks like the specs are the same for both. So these are the correct crossovers for monitor 7 series 2s?
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The inductor in the last photo is the wrong one for the Monitor 7. It is, as the label states, for the Monitor 5jr+.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 -
Both crossovers have a cap that is 8uf and one that is 27 MFD.
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5jr+ MW inductor on the one with correct 7 crossovers on both then.
So, the 5jr+ inductor would be the one sounding "boomy" or vice versa?
Brian
One-owner Polk Audio RTA 15TL speakers refreshed w/ Sonicap, Vishay/Mills and Cardas components by "pitdogg2," "xschop" billet tweeter plates and BH5 | Stereo REL Acoustics T/5x subwoofers w/ Bassline Blue cables | Rogue Audio Cronus Magnum III integrated tube amp | Technics SL-1210G turntable w/ Ortofon 2M Black LVB 250 MM cart | Sony CDP-508ESD CD player (as a transport) | LampizatOr Baltic 4 tube DAC | Nordost & DH Labs cables/interconnects | APC H15 Power Conditioner | GIK Acoustics room treatments | Degritter RCM -
So maybe you could send your one hacked crossover large inductor cup to @westmassguy if he has time and he could wind you a new inductor or simply add on to it to get the correct inductance. Need to go from 0.56mH to 1.75mH. It might be doable especially since it appears they used 18awg for both. Wouldn't be a bad idea to send him both and he can match them up to a tight tolerance.
And you will need to get RD0198 tweetersGeorge / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Onkyo A-8017 integrated
Logitech Squeezebox Touch Streamer w/EDO applet
iFi nano iDSD DAC
iPurifier3
iDefender w/ iPower PS
Custom Steve Wilson 1m UPOCC Interconnect
iFi Mercury 0.5m OFHC continuous cast copper USB cable
Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
Custom Vibration Isolation Speaker Stands and Sub Platform -
Thanks for all the replies and suggestions!
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could it be that polk accidentally put the wrong sticker on it? Not sure how to test the inductors, but wouldn't that be the first step?M7's 1982 Peerless tweeters
M5's X2 (1981 Peerless tweeters, 1988 with upgraded tweeters)
M4's X2 both with Peerless tweeters
M5Jr with SL1500 (in the garage, they sound great)
M4.6 series2 X2 with upgraded tweeters
SDA 2 with upgraded tweeters
