L600 Polarity Issue

AgentTJ

Hello Polk Community and Support,

I recently purchased a pair of the Polk L600's. Was very excited and hooked them up right away. Hooked them up to my Emotiva DR2 Amp (which has only the RCA inputs being used from the pre-amp).

Upon running my Denon pre-amp Multi EQ I received a message the front two channels were out of phase vs the remaining of my 5.2 setup.

Through some testing, both audio test and a battery test I believe to have confirmed the speakers are in fact wired internally backwards.

I first must say I love the speakers in a stereo setup and have been enjoying them very much for the past week. What I ended up doing was hooking them up "backwards" or how I believe to be correct which is producing an excellent front channels to a 5.2 listening experience.

I have raised this issue with Polk audio support approx 1 week ago now with no progress on the issue (not even an answer). I'm a bit disappointed how difficult it is to get someone technical from Polk on the phone, email, chat, etc.

I'm afraid I may simply need to return or possibly exchange the speakers if nothing else can be done (not sure anything else can be).

Anyone else experienced this with their set and what is everyone's opinion on Polks customer service. I've been a lifelong "aspiring" audiophile and this is the biggest single purchase I've made in the hobby so far. Bit saddened about diving in with the L600 feeling like support is MIA...

Emlyn

It’s normal with the auto setup microphone systems to alert to speakers being out of phase. The speakers are not wired out of phase. It happens with most speakers I have had over the last decade.

stangman67

Audessey setup is notorious for reporting that speakers are out of phase when in fact they are not. Listen to music, you should be easily able to tell

AgentTJ

What are your thoughts on the fact I've battery tested them and found them to be backwards? Shouldn't this all but confirm the issue?

F1nut

Is this what the back of yours looks like?

AgentTJ

Hi f1nut, yes exactly. Hooking a battery to the back of the speaker, positive to positive and negative to negative results in the woofers moving inward. I'm currently using them hooked up in reverse as a result.

F1nut

AgentTJ wrote: »

What are your thoughts on the fact I've battery tested them and found them to be backwards? Shouldn't this all but confirm the issue?

Exactly how did you perform this test?

mhardy6647

I presume your battery test was applied to each loudspeaker, and in once case the woofers moved "out", and in the other case, they moved "in"?

If you're certain that the polarity of the inputs on one of the two loudspeakers is inverted -- why not simply hook that one up with reversed polarity from your amplifier/speaker cable (i.e., + to - and - to + ; or red to black & black to red, so to speak)?
That should fix the problem!

"white noise" is a good test of speaker polarity. The Stereohile test CD has "in phase" and "out of phase" noise on it, clearly indicated, to do the test, or if you have an FM tuner or receiver, set the tuner to "mono", turn off the "muting" and listen to the static-like noise between stations. If the two speakers are wired correctly, the noise will be dead center between the two loudspeakers. If one is reversed in polarity with respect to the other, the noise will be much more diffuse. You can swap cables (ideally, with the amplifier or receiver turned off, just in case!) and hear the difference.

As an aside: The best tool I know of for really testing polarity of a speaker, a driver, or a cable is the Galaxy Cricket. Maybe not something you want to procure just for this exercise (although not really very expensive), but a very handy (nigh-on invaluable) tool for installation, DIY loudspeaker construction, and troubleshooting.


https://galaxyaudio.com/products/cpts/

stangman67

Did you test both l600’s?

AgentTJ

Hi mhardy, thanks for your reply. Correct on your thoughts from the battery test. I have them hooked up currently how I believe is "correct". They sound great, I think my biggest concern is how when raised to Polk they are not responsive to my incident case. I am less worried about my listening experience (because I can simply wire them in phase as you mentioned) and instead their resale value or secondary market value should I choose to part with these a long time from now. Explaining this to another person is not likely to go well IMO. should I just return/exchange these for a properly wired pair?

AgentTJ

Yes stangman, tested both. Also tested my entire surround setup (diff brands).

mhardy6647

I cannot find an on-line file or video using white (or pink) noise, but this one is OK. The only problem is: you can hear the difference between correct & reverse polarity, but it may be hard to know right from wrong! The 'correct' reproduction should be centered between the two channels. I just listened on a laptop moments ago, so I am not certain that's what you'll hear on a proper hifi.

https://youtu.be/bsEos4kwj_o

F1nut

AgentTJ wrote: »

Hi f1nut, yes exactly. Hooking a battery to the back of the speaker, positive to positive and negative to negative results in the woofers moving inward. I'm currently using them hooked up in reverse as a result.

That certainly indicates they are wired incorrectly.

Unfortunately, Polk CS isn't what it once was. Did you buy them direct or from a dealer?

This is the direct email to the person at Polk who gets things done.
Kim.Jasper@soundunited.com

AgentTJ

Purchased direct from Polk

stangman67

We can all agree that Polk CS has gone mostly the way of the dodo. I wouldn’t trust audessey but if your battery test is going the way you say it is, then you are correct. For me, I would want to get the incorrect one replaced, just for peace of mind

AgentTJ

Cool, thank you all. Glad to have your confirmation. Appreciate it.

Polk CS, time to step it up!

stangman67

AgentTJ wrote: »

Cool, thank you all. Glad to have your confirmation. Appreciate it.

Polk CS, time to step it up!

Did you buy direct from Polk? If not, go through whoever you bought from

Emlyn

If the speaker wires are connected out of phase and the auto setup run again are the main speakers no longer reported as being out of phase by the auto calibration system?

AgentTJ

That's correct Emlyn

Emlyn

Maybe another forum member who owns the L600s can battery test their speakers the same way you have and see if the results are the same. Would save returning a pair only to find the replacement pair does the same thing.

It could just be that's the way the speaker drivers and crossover are designed internally. It's not unusual for speakers that do stereo and home theater duty. Focal actually recommends running Audyssey with reverse polarity on the speaker wires if the auto calibration says the main speakers are out of phase then putting the speaker wire back in phase after auto calibration is done.

stangman67

@Emlyn either way both speakers should act the same way when given voltage. Speaker manufactures do not make speakers out of phase from each other

Emlyn

True. The same model speakers should behave the same way electrically and acoustically as one another but the individual drivers in the speakers can be deliberately set up internally, working with the crossover, to not all be in phase with each other in the same cabinet. That's not at all unusual.

If I had a question in my mind about internal wiring problems I would battery test both L600s for the same behavior and see if another forum member, or a Polk engineer, finds the same behavior.

stangman67

I guess the op never answered this question. Do both speakers behave the same when voltage is applied? Or differently?

AgentTJ

Both speakers behave the exact same way when tested with the battery.

stangman67

Yea I would argue it is unlikely that both speakers are wired incorrectly. Not saying yo I are doing the test wrong, I’d bet that the speaker is just designed that way. Not so sure I’d be worried if both speakers are behaving the same exact way

pitdogg2

One way to find out is open them up and look. Is the positive binding post going to the positive side of the XO ? Is that then going to the positive side of the drivers?
In rare instances the phase gets shifted (reversed) in the XO and must be corrected at the end, meaning positive wire goes to negative side of a driver.

This is the direct email to the person at Polk who gets things done.
Kim.Jasper@soundunited.com

I would email Kim he knows his stuff and can help you

AgentTJ

Stang, i totally agree with you, seems that way and would be weird to have them both be incorrect if not on purpose. But in order to have them in phase with my other brand (rears and center) I had to reverse them.

pitdogg2, I def thought about doing this but was concerned about voiding my warranty or anything on them. Thoughts?

stangman67

If all you had to do was swap the leads and you are happy, let it ride. You can verify with Polk, but I certainly wouldn’t open them up personally. No reason to potentially mess something up when there isn’t a real issue.

Emlyn

When you have guests over you could impress them by saying you discovered that running the mains in phase with the rest of the speakers produces a better soundstage.

stangman67

What’s interesting is both preamps I have had in my system are wired with reverse polarity, now the difference was they stated the fact in the manual so I knew I had to reverse the speaker leads!

Interesting if the L600’s are intentionally wired reverse polarity.

AgentTJ

So Kim from Polk responded to my email with very helpful information. I'd like to share the jist of it here for others below. This looks like my reversing the wires is correct with a speaker with a 2nd order crossover, while my other brands do not invert phase.

"The L600’s employ second order filters in the crossover design and this type of crossover / filter does invert phase so this is normal.

First order and third order filters are phase correct. Second order and fourth order filters invert phase.

Attached below is link that may help better explain this.



https://www.calsci.com/audio/X-Overs4.html



Hope this helps."


Thanks all!