5JR crossover upgrades and questions
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57cessna172
Posts: 10
All,
I’ve searched the threads as best I can. I’m looking for pictures on how to upgrade the crossovers on my 5JR’s. I’ve had them since 88, and they’ve been great all these years. A couple of months ago one of my tweeters stopped working. I’ve bought the items needed to upgrade. Specifically new RDO198’s, sonic caps 13UF and the resistors, I can solder and all that. Just not really sure where the new parts go. As they say, pictures are work a thousand words. I’m an newb for this.
I’ve searched the threads as best I can. I’m looking for pictures on how to upgrade the crossovers on my 5JR’s. I’ve had them since 88, and they’ve been great all these years. A couple of months ago one of my tweeters stopped working. I’ve bought the items needed to upgrade. Specifically new RDO198’s, sonic caps 13UF and the resistors, I can solder and all that. Just not really sure where the new parts go. As they say, pictures are work a thousand words. I’m an newb for this.
Comments
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Watching this thread since I have a pair of 5Jrs I'd like to upgrade as well.
Are 198s correct for the 5Jr? I thought the 194s were the uograde/replacement.I disabled signatures. -
The tweeter would depend on which 5jr version he has.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 -
OP, you'll never fit all of that on the original board. One option is to mount the new components on a separate board and run leads to the original board. Another option is to make an entire new point to point wired crossover.
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 -
Original tweeter is an sl2000. F1nut, have any links to accomplish what your suggesting?
I’ve seen pics of different crossovers having the components being mounted on the back of the board. -
In that case you bought the wrong tweeters, you want the RD0194.
No links that I'm aware of, but some searching online should turn up something.
The problem you have is a serious lack of real estate.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 -
Maybe some pics will help. This is a Baby Advent point to point job I did.
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 -
This is a Pioneer, but the model escapes me.
Before:
After:
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 -
This is the Monitor 7B.
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 -
Thanks for the information, I had ordered the 198’s prior to removing mine. Didn’t catch that mine had the sl2000’s until now. Curious. What’s the difference between the sl2000 and the sl2500?
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This thread goes into it:
https://forum.polkaudio.com/discussion/182943/the-tale-of-5-tweeters-sda-tweeter-replacement-guide/p1George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Crown D150 amp
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 the link. Looks like I’ve jumped the gun on ordering parts. I based the parts bought on it appears series 2 JR’s. Guess I’ll see if I can return the 198’s for some 194’s.
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Or follow the revised 5jr+ schematics if yours has a passive radiator. That model could use the rdo198
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Pitdogg2, thanks. I think that might work. Going over the schematic now.
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I checked the schematics out of curiosity. When Polk went from the SL2000 in the 5jr+ schematic (6/1/89) to the SL2500 5jr+ S schematic (3/21/90) the only change they made was they increased the value of the capacitor from 12uf to 13uf? That's such a small increase that it is almost within the tolerance of +/-5%! The nom. impecances of SL2000 vs SL2500 is 7.3Ohm vs 5.7Ohm......pretty big difference. Kind of amazing that they basically made very little change to the crossover.
PS: If they also added a passive radiator at this time perhaps that could help explain it?Post edited by Gardenstater onGeorge / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Crown D150 amp
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 -
Think I'm going to use the schematic for the 5JR + and stick with the parts I have. I identified the poly switch and have replaced those with a jumper. Will work on install of the capacitors next.
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if the tweeter is too forward you'll need a 12watt mills .5ohm resistor
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Pitdogg, can you enlighten me on where the resistor would go? Guessing inline with the positive side of the tweeter? (I have the resistors on hand)
Thanks! -
57cessna172 wrote: »Pitdogg, can you enlighten me on where the resistor would go? Guessing inline with the positive side of the tweeter? (I have the resistors on hand)
Thanks!
Resistor goes where you put the jumper for the polyswitch. We usually remove the polyswitch and add the resistor to make up for the resistance of the polyswitch. -
Copy that
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57cessna172 wrote: »Think I'm going to use the schematic for the 5JR + and stick with the parts I have. I identified the poly switch and have replaced those with a jumper. Will work on install of the capacitors next.
This doesn't seem to have been a well thought out plan. Using two 6.8uF instead of a single 13uF, not replacing the poly with a resistor, buying the wrong tweeters and not figuring out how/where to put everything before hand. Sometimes it's best to punt and start fresh. Good luck.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 -
Thanks. I ordered the 6.8's to make it a total of 13.6UF. The prints for the M5JR+'s show a 13.5UF.
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Yeah that was my bad. I should've rotated the pdf to make it easier to read. 13.5uf (not 13 like I said ^^^)George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Crown D150 amp
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 -
57cessna172 wrote: »Thanks. I ordered the 6.8's to make it a total of 13.6UF. The prints for the M5JR+'s show a 13.5UF.
I stand corrected on that one
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 installed the resistor in place of the poly switch and installed the two 6.8UF's in series. Installed new RDO198's and put the crossovers back in. Both speakers work and sound much better than they did before. Thanks everyone for the help on this. Hope the pics help someone else who is new to all of this. Please excuse the dirty solder joints. Pic was taken prior to cleaning the boards of the extra flux.
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I hope you put the two 6.8uf caps in parallel (not series). Parallel capacitors add.George / NJ
Polk 7B main speakers, std. mods+ (1979, orig owner)
Martin Logan Dynamo sub w/6ft 14awg Power Cord
Crown D150 amp
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 -
Gardenstater wrote: »I hope you put the two 6.8uf caps in parallel (not series). Parallel capacitors add.
^This!
Also I know pictures frequently make things look worse than they are, but it looks like your boards could use a good cleaning with alcohol and a brush (not a wire brush). I was taught that flux can be corrosive and nasty if left on solder joint. Don't know if that is true, but I have always cleaned up the boards to be best of my ability when I finish my solder work.SDA SRS 2.3tl, SDA 1C, SDA 2B (TL mod), Reserve 200
