SDA 2.3 No bass

tragusa3 · July 10

HOLD THE PHONE: Please say that I stumbled into something!!! Hard to show it in this picture, but this is the right speaker, drivers in the array of two. The black wire on the driver to the left is on + as it should be. When I trace it to the driver on the right, it is black with a white marker, but is on negative? Those two drivers shouldn't be out of phase? Should they? OTHER cabinet is the same way...maybe it is supposed to be.

Clipdat · July 10

VR3 · July 10

I have ran the big Polks with no passive resistor installed and they will shake the house with the worst bloated bass you will ever hear.

If all of the drivers are working I think you have a phasing issue somewhere

tragusa3 · July 10

With both cabinets being this way, I don't think I found a problem. But does this mean the stereo array drivers are out of phase with each other? odd.

Gardenstater · July 10

tragusa3 wrote: »

HOLD THE PHONE: Please say that I stumbled into something!!! Hard to show it in this picture, but this is the right speaker, drivers in the array of two. The black wire on the driver to the left is on + as it should be. When I trace it to the driver on the right, it is black with a white marker, but is on negative? Those two drivers shouldn't be out of phase? Should they? OTHER cabinet is the same way...maybe it is supposed to be.

According to the schematic they are supposed to be in series. So one driver would have its positive terminal connected to the appropriate terminal on the PCB and then there should be a wire going from the negative terminal to the positive on the second driver. Then there should be a wire going from that driver's negative back to the PCB at appropriate place.

skipshot12 · July 10

Now you’re cooking big daddy.
Could be something that simple. Tracing out everything will eliminate what’s not wrong.

tragusa3 · July 10

Gardenstater wrote: »

tragusa3 wrote: »

HOLD THE PHONE: Please say that I stumbled into something!!! Hard to show it in this picture, but this is the right speaker, drivers in the array of two. The black wire on the driver to the left is on + as it should be. When I trace it to the driver on the right, it is black with a white marker, but is on negative? Those two drivers shouldn't be out of phase? Should they? OTHER cabinet is the same way...maybe it is supposed to be.

According to the schematic they are supposed to be in series. So one driver would have its positive terminal connected to the appropriate terminal on the PCB and then there should be a wire going from the negative terminal to the positive on the second driver. Then there should be a wire going from that driver's negative back to the PCB at appropriate place.

So I got excited too soon. it's part of the design. Oh well...I'll keep trucking.

Skepshot, I'm going to figure it out.

Gardenstater · July 10

I can't really tell from your picture if it is correct. I "think" that the bottom stereo driver's positive should have a black wire going to it from the PCB. Then there should be a black wire with a white marker going from that driver's negative to the upper driver's positive. Then there should be a white wire going from that driver's negative back to the PCB.

tragusa3 · July 10

That is how it is wired.

tragusa3 · July 10

Clipdat wrote: »

My uneducated **** says it's something wrong with the crossover.

Has a bad/old capacitor been known to completly choke out bass?

VR3 · July 10

If the capacitor is open or way out of spec it is in parallel to the driver and definitely would cause issues

gmcman · July 10

How is your room setup? Pics? Any other floor standing speakers placed nearby that aren't in use?

Trying to rule out a large bass suckout somewhere.

tragusa3 · July 10

gmcman wrote: »

How is your room setup? Pics? Any other floor standing speakers placed nearby that aren't in use?

Trying to rule out a large bass suckout somewhere.

The room is not ideal, but I have done lots of moving of placement and even brought them into the neighboring room with no success. On top of that, 6 or so other speaker pairs have had prodigious bass in the same position. Thanks for your input.

tragusa3 · July 10

VR3 wrote: »

If the capacitor is open or way out of spec it is in parallel to the driver and definitely would cause issues

Can I test the capacitors while on the crossover board? How would I?

nooshinjohn · July 10

Reseal the cabinets, rebuild the crossovers, replacing the inductors as well. Get some Armacell Armaflex TAP18230 Insulation Tape from Home Depot to replace the gaskets. Inspect all drivers and the passives for small tears in the surrounds. Replace the wiring harnesses and reassemble. This will eliminate every potential point of failure within the speakers for the problems you are having. At this point, you are chasing so many variables trying to solve an issue that would be corrected by just biting the bullet and doing what you already know needs to be done anyway.

Gardenstater · July 10

I don't like the fact that Polk didn't show the drivers and their wiring arrangement in the schematic. I don't think they failed to do that in later schematics I have seen. I think you need to try to do a sketch of how they are wired in your speakers.

Going back to the first page of this thread where you posted the below wiring diagrams with your notes, I am troubled by the fact that the dimensional drivers pulled in and all the other drivers pushed out, I'm assuming when you put a battery across the binding posts?

I also see that you show for the dimensional drivers Blue as negative and Green as positive and I think Polk convention was the opposite of that. It was in the 2.3tl wiring diagrams. Maybe your polarity of the dimensional drivers is incorrect.

PS: Not that I'm trying to give you more homework 🤣

nooshinjohn · July 10

The dimensional drivers are purposely out of phase.

xschop · July 10

Not only are they out of phase, but follow any other later SDA scheme where the stereo driver or drivers are wired for 6.5 ohms and the dimensional driver/s are wired for 3.5 ohms.

Gardenstater · July 10

I'm inexperienced with SDA but I don't see where they are out of phase in either the 2.3 or 2.3tl schematics. Also as I said I don't think Polk would have changed wiring conventions of Blue being positive and Green being negative. Maybe I'm missing something. He needs to find everything that is wrong and fix it and the problem will hopefully get taken care of along the line. Somebody was monkeying around with these speakers and there isn't a clear schematic on how to wire the drivers up, really.

pitdogg2 · July 10

2.3tl and 2.3 are completely different critters.

VR3 · July 10

Very

SCompRacer · July 10

tragusa3 wrote: »

Can I test the capacitors while on the crossover board? How would I?

You'd need an ESR tester like the Capacitor Wizard. ~$200. In circuit testing isn't always reliable though. If I get a questionable reading from the Wizard, I always disconnect one side of capacitor and retest the capacitor only, not the circuit it is connected to. Sometimes the Wizard reads "compare" and I have to test the cap with a Sencore capacitor analyzer.

You have a multimeter that measures capacitance? Again, not always reliable unless you disconnect one end of the capacitor.

Always disconnect power and drain a capacitor before any testing.

tragusa3 · July 10

nooshinjohn wrote: »

Reseal the cabinets, rebuild the crossovers, replacing the inductors as well. Get some Armacell Armaflex TAP18230 Insulation Tape from Home Depot to replace the gaskets. Inspect all drivers and the passives for small tears in the surrounds. Replace the wiring harnesses and reassemble. This will eliminate every potential point of failure within the speakers for the problems you are having. At this point, you are chasing so many variables trying to solve an issue that would be corrected by just biting the bullet and doing what you already know needs to be done anyway.

I didn't consider the crossover rebuild to be "biting the bullet". I've rebuilt several sets in the past, although vintage Klipsch crossovers are far simpler than these. Since it was obvious someone had been inside these cabinets, I'm doing my diligence to rule out as much as I can first. I'm satisfied I've done all I can outside of the crossover. So begins the next chapter. I have to own being all over the place. LOL

tragusa3 · July 10

George, I forget now where I saw it, but having the dimensional drivers out of phase was to be expected in the battery test (yes, battery to binding posts). In essence, that test alone proves wiring to be correct. It's got to be in these crossovers. I've been reluctant to believe they could be responsible for something as drastic as I measured, because I've rebuilt them in the past and haven't noticed much change in any case. But, we are all about to find out.

tragusa3 · July 10

SCompRacer wrote: »

tragusa3 wrote: »

Can I test the capacitors while on the crossover board? How would I?

You'd need an ESR tester like the Capacitor Wizard. ~$200. In circuit testing isn't always reliable though. If I get a questionable reading from the Wizard, I always disconnect one side of capacitor and retest the capacitor only, not the circuit it is connected to. Sometimes the Wizard reads "compare" and I have to test the cap with a Sencore capacitor analyzer.

You have a multimeter that measures capacitance? Again, not always reliable unless you disconnect one end of the capacitor.

Always disconnect power and drain a capacitor before any testing.

Well...cheaper for me to take the chance on rebuilding (which I would have done either way) than to buy the equipment.

If I use a DC device connected to the removed capacitor, will it drain it? Is that how it's done easiest?

pitdogg2 · July 10

Blue or black wire is positive.
Green or white is negative.
Black and white will be on stereo drivers.
Blue and green dimensional drivers.
On the big SDA speakers you will have some wires taped the color they "become" when hooked in series with another driver.
@Gardenstater sometimes silence is golden when you do not know the answer.
The wiring schematic is in here for the 2.3.

https://forum.polkaudio.com/discussion/55888/polk-audio-speaker-wiring-schematics-amp-more-stereo-dimensional-array-sda#latest

SCompRacer · July 10

A resistor can be used, an incandescent light bulb, shorting across leads if it is a low voltage.

The light bulb gives you a visual and something to watch counting down. Doubtful you'd get a 60 watt bulb to light with a crossover cap. Check cap with voltmeter before testing.

Gardenstater · July 10

I would check to make sure the + terminals of the dimensional drivers are connected to the end of the 1.23mH inductor (other side from binding post side) because the schematic clearly shows that. The 1.23mH inductor would be the 3rd largest one in size.

I have never heard that Polk ever changed Blue is positive, Green is negative convention, or I should say that they ever had it the opposite of that.

Gardenstater · July 10

And you think those are different from the ones that OP and I have already posted? Or that your wiring conventions are different from what I said above?

vulcan · July 10

The DCR readings can be obtained more easily from the terminal cup.
Use red and black speaker binding posts. The interconnect(IC) cable points are blade is pin#1 and the pin is pin#2

SDA 2.3 No bass

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