Differences in Polk SDA Compact crossovers
tiburonhombre
Posts: 7
I have two sets of Polk SDA Compact speakers from 1984 and 1986. These are the Polks with two tweeters and two mid-range speakers plus the passive radiator.
The crossovers in each set of speakers are slightly different from each other. In the 1984 crossovers there are two wires that connect the stereo and dimensional crossovers together. The IC wires in the '84 versions connects to the dimensional crossover only. In the 1986 crossovers there is only one black wire that connects the stereo and dimensional crossovers. The IC wires in the '86 versions connects one wire to the stereo crossover and one wire that connects to the dimensional crossover (or so that's how I marked them before disassembly)
Now to my problem:
I just completed replacing the capacitors and resistors in the '86 crossovers with Dayton caps and Mills resistors. In '86 they used polyswitches, which I removed and jumped with a piece of copper wire.
I reassembled one speaker, anxious to see how it worked, hooking it up sans IC cable. There is sound from the mid range speakers but nothing from the tweeters.
Is this because there must be two speakers hooked up with the IC cable, because I connected the IC wires and crossover connections incorrectly or another error in replacing the Caps/Resistors.
These are not the first speakers that I have recapped but these are the first Polks and they were challenging and time consuming due to the number of parts.
The crossovers in each set of speakers are slightly different from each other. In the 1984 crossovers there are two wires that connect the stereo and dimensional crossovers together. The IC wires in the '84 versions connects to the dimensional crossover only. In the 1986 crossovers there is only one black wire that connects the stereo and dimensional crossovers. The IC wires in the '86 versions connects one wire to the stereo crossover and one wire that connects to the dimensional crossover (or so that's how I marked them before disassembly)
Now to my problem:
I just completed replacing the capacitors and resistors in the '86 crossovers with Dayton caps and Mills resistors. In '86 they used polyswitches, which I removed and jumped with a piece of copper wire.
I reassembled one speaker, anxious to see how it worked, hooking it up sans IC cable. There is sound from the mid range speakers but nothing from the tweeters.
Is this because there must be two speakers hooked up with the IC cable, because I connected the IC wires and crossover connections incorrectly or another error in replacing the Caps/Resistors.
These are not the first speakers that I have recapped but these are the first Polks and they were challenging and time consuming due to the number of parts.
Comments
-
Recheck your connections and the work you did on the boards because you got something wrong.
Other than that, you should use a .5 ohm resistor in place of the poly to compensate for the designed in resistance of said poly. Also, consider using better caps in the high frequency circuit, Daytons are pretty rough.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 used Dayton 1% caps where I could on the high pass. I was aware of using .5 ohm resistor in place of poly switch but room was limited with the larger caps. The following are photos of the crossovers. Anyone see any obvious problems wit the way I assembled the Caps/resistors:
-
They appear to be ok, one thing I notice make sure the boards are fastened solidly to the spool inductor to prevent movement and vibration noise and use only non metallic or aluminum fasteners.Yamaha RXA1030, Yamaha CD-S2100, Yamaha AS-2200, Bluesound node 2i
Polk SDA2btl highly modded
Polk SDA 1C modded
Polk CS350 LS x2
Kimber 8TC
Sony 55" Bravia
Wish list SVS sub
