Mistake - or worth trying?

Uilleann

Hey guys,

I've had a Polk PSW110 10" sub in the music/ht setup for about 5 years now, paired up with a set of TSx 440Ts up front, TSi300s for the rear surrounds and a CS10 center. An old Denon 1910 holds it all together.

My question pertains to the sub in particular. I know some speaker manufacturers will supply plugs for the ports on their speakers or subs to change the characteristics of the tone. While the PWS110 doesn't come with a plug, I wonder if crafting one and trying it out might cause any potential damage to driver or amp? Ideally, the sub is good, but remains just a bit 'boomy' for music. I've run numerous Audessey set ups, and tried with some different placements around the room - with very little change.

I'm going to try a few more placement options, but due to the shape of the room, furniture placement requirements and two silly chocolate Labs with tails that destroy everything in sight, and drool to top it all off - my options are a little bit limited.

In short, apart from the potential change in response and tone, can anyone think of electronic or mechanical reasons this may not be a wise experiment to undertake with the PSW110? If I'm likely to kill the on board amp, or damage voice coils or suspension, obviously I'll give it a miss...

Thanks for letting me ponder out loud as it were.

Cheers

Brian~

rooftop59

Hi Brian,

I've tried that in the past with a couple different subs, and honestly it never helped. You have one or more or several problems with the sub, only one of which is even potentially addressed by the port plug:

1. An uneven frequency response, which lends to a "boomy" sound (some frequencies are louder than others)

2. The amp is underpowered, leading to distortion when pushed, which messes up the tonal quality and just sounds bad

3. The port is tuned too low, exacerbating the uneven frequency response and leading to chuffing or port noise at high volumes.

Only #3 will be addressed by plugging the port, but at the expense of both extension and output. It will also put more stress on the amp. So I would not recommend it. If you want to fix the problem save your pennies for a better sub, or if you have the skills and tools, built one. Me and my bro-in-law did that, it was a lot of fun and sounds awesome for a lot less money.

Good luck!

tonyb

Uilleann wrote: »

Hey guys,

I've had a Polk PSW110 10" sub in the music/ht setup for about 5 years now, paired up with a set of TSx 440Ts up front, TSi300s for the rear surrounds and a CS10 center. An old Denon 1910 holds it all together.

My question pertains to the sub in particular. I know some speaker manufacturers will supply plugs for the ports on their speakers or subs to change the characteristics of the tone. While the PWS110 doesn't come with a plug, I wonder if crafting one and trying it out might cause any potential damage to driver or amp? Ideally, the sub is good, but remains just a bit 'boomy' for music. I've run numerous Audessey set ups, and tried with some different placements around the room - with very little change.

I'm going to try a few more placement options, but due to the shape of the room, furniture placement requirements and two silly chocolate Labs with tails that destroy everything in sight, and drool to top it all off - my options are a little bit limited.

In short, apart from the potential change in response and tone, can anyone think of electronic or mechanical reasons this may not be a wise experiment to undertake with the PSW110? If I'm likely to kill the on board amp, or damage voice coils or suspension, obviously I'll give it a miss...

Thanks for letting me ponder out loud as it were.

Cheers

Brian~

Hi Brian,
Couple Labs huh....nice pups that just want to play all day. Lets see if we can help ya out some. Your auto calibration is just a guide, those settings are not written in stone as the most optimal. Adjust your sub setting in the receivers menu in small increments to see if you get some better sound. It's a matter of finding a balance in the settings that work well for both movies and music. The PSW series of subs are mostly designed for HT use though, but that doesn't mean they can't be used for music also. Personally, I like to adjust the settings for music first, and usually those are also good enough for movies.

I'm assuming you have the sub set up from the receivers sub out ? Make sure then the crossover on the sub is set to it's highest value to take it out of the equation. Otherwise you have some double filtering going on along with the receivers bass management, which can contribute to that boomy sound. If the sub is placed in a corner, that may also contribute to the bass loading up in that corner creating a bit of a boomy sound too. Too close to walls is also not good, experiment a bit and see what you can do, sometimes a few inches can make or break the sound.

Many like to use an alternative hookup. Hook up the speakers to the sub and use speaker wire from the receiver into the subs speaker inputs. You would then in your receivers menu set sub to "no", turning off the receivers bass management for the sub.Turn those front speakers to large in the receivers menu too. Instead, you now use the crossover on the subwoofer and start at about 80 and adjust from there playing your favorite music tracks. Star with the volume on the sub at about 40% and also adjust in small increments at a time. Yes, the sub will still play all the nice booms in your movies too.

You've already covered placement, and we can only do what we can do in our given situations. I wouldn't suggest plugging ports. Good luck to you and let us know how or if you achieved better performance.

Uilleann

This is their 'cute' face...likely just before or after they ate/chewed/broke something.

As for the sub itself, I don't think I have a defective amplifier section as Rooftop suggests, as it plays nicely enough - just boomy with both movies and music. As for the design, it's a Polk - they tend to do their homework. Though, perhaps this particular design was built to cater much more to the HT crowd rather than the music crowd. Seems silly to me though, that a driver and enclosure would be made with so much weight in one direction. Still not sure if that's actually the case here.

Tony, you make some great suggestions here. Let me see what I can tick off the list right away, and narrow things down from there.

Dennon 1910 (2010 model I believe) is the AVR, and yes, we're coming out of the LFE output via an overpriced Monster "sub" RCA type cable.

Input is correct for this sub using the Left (LFE) input on the back.

Crossover was set closer to 100, so bumped all the way to the upper stop and will re-run Audyssey. Good catch there, thanks!

Placement is currently close to a corner, but not shoved hard into one if you follow me. I'm about 18 inches from one wall, and about 6 from the other. This sub has a downward firing port, with the main 10" driver facing out into the room. We have hardwood floors, and the walls are a 1939 lath and plaster vintage - not sure if that plays into things much here or not.

The room itself is 33' long, 11' 8" wide, & 8' 4" tall with a slight curved blend from the top of the walls to the ceiling. Our couch (and MLP) are on one long wall, and the A/V system is on the opposite, approx 8.5' to the mains, and 12 to the sub off to the right side. There is a window immediately behind the couch, which is covered with a medium thickness curtain. The couch is fabric as opposed to leather - though again, I'm not sure if that sort of minutiae has any measurable impact on the lower frequencies or not.

Don't think I'm brave enough to attempt the speaker level inputs to the sub yet, mostly because our room and furniture requires some heavy lifting anytime any wire needs to be moved or changed - it's not an easy or quick task in our set up. With that said, I wonder about moving the sub to the opposite (left) side of the mains putting it closer to the center of the room overall, but would still need to be close to the wall. Though, as I think about it, I seem to recall reading somewhere that central placement of a sub in a room was less than ideal?

Your thoughts?

B~

felipe

Uilleann wrote: »

This is their 'cute' face...likely just before or after they ate/chewed/broke something.

As for the sub itself, I don't think I have a defective amplifier section as Rooftop suggests, as it plays nicely enough - just boomy with both movies and music. As for the design, it's a Polk - they tend to do their homework. Though, perhaps this particular design was built to cater much more to the HT crowd rather than the music crowd. Seems silly to me though, that a driver and enclosure would be made with so much weight in one direction. Still not sure if that's actually the case here.

Tony, you make some great suggestions here. Let me see what I can tick off the list right away, and narrow things down from there.

Dennon 1910 (2010 model I believe) is the AVR, and yes, we're coming out of the LFE output via an overpriced Monster "sub" RCA type cable.

Input is correct for this sub using the Left (LFE) input on the back.

Crossover was set closer to 100, so bumped all the way to the upper stop and will re-run Audyssey. Good catch there, thanks!

Placement is currently close to a corner, but not shoved hard into one if you follow me. I'm about 18 inches from one wall, and about 6 from the other. This sub has a downward firing port, with the main 10" driver facing out into the room. We have hardwood floors, and the walls are a 1939 lath and plaster vintage - not sure if that plays into things much here or not.

The room itself is 33' long, 11' 8" wide, & 8' 4" tall with a slight curved blend from the top of the walls to the ceiling. Our couch (and MLP) are on one long wall, and the A/V system is on the opposite, approx 8.5' to the mains, and 12 to the sub off to the right side. There is a window immediately behind the couch, which is covered with a medium thickness curtain. The couch is fabric as opposed to leather - though again, I'm not sure if that sort of minutiae has any measurable impact on the lower frequencies or not.

Don't think I'm brave enough to attempt the speaker level inputs to the sub yet, mostly because our room and furniture requires some heavy lifting anytime any wire needs to be moved or changed - it's not an easy or quick task in our set up. With that said, I wonder about moving the sub to the opposite (left) side of the mains putting it closer to the center of the room overall, but would still need to be close to the wall. Though, as I think about it, I seem to recall reading somewhere that central placement of a sub in a room was less than ideal?

Your thoughts?

B~

First I would like to say you have beautiful dogs . Having owned the PSW110 before, and I never found it to be boomy at all...actually to me it was more on the musical side. I'm thinking the boominess you are experiencing is from the hardwood floors you have,since its port is bottom firing. You could try putting something like a bath rug or something of the sort underneath it? That might take care of some of the boominess...since you have a lot of hard surfaces. Hope this helps

drumminman

If you have the crossover set to 100 that's probably too high. It's doing too much work. Try setting it to 60 so the mains take more of the load.Polks website shows that the reach down to 33 hz, so I wouldn't think 60 would be an issue. I would even try a little lower to see how it sounds.

Uilleann

I'll look into something carpet-esque to try underneath ad see if it helps with the port location. That was part of my initial pondering about the effects of plugging the port on this particular Polk model. As far as the X-over frequency, when running Audyssey it is important (as I was astutely reminded earlier in this thread) not to turn down the frequency. That is left to the room correction software. Using the filter on the sub often negates the bass management of the algorithm /software.

So I'm left to wonder if it's a classic case of corner loading gone horribly wrong - coupled with the hardwood floors. It also looks like I made an error in my typing of the dimensions of the room earlier. The space is 23 feet long - not 33 in the longest dimension (the squares on the grid are 1 foot each). The layout of the room currently looks something close to this:



I don't know nearly enough about room nodes and it's associated affect on frequencies below 300 Hz. I'm sure there are several large and frightening equations that might be able to shed more light on my situation by those far more intelligent than myself. But it' the weekend...and scary maths make my head hurt!

I'm thinking I may still look at pulling the sub out, and moving it over to the other side of the AVR cabinet - closer to the door to the dining room. It requires a deal of heavy lifting (the cabinet empty itself weighs over 700 pounds!) and some tweaking to the wiring to make that go. So I haven't been in a big rush so far to make that change just yet.

Brian~

rooftop59

Uilleann wrote: »

As for the sub itself, I don't think I have a defective amplifier section as Rooftop suggests, as it plays nicely enough - just boomy with both movies and music. As for the design, it's a Polk - they tend to do their homework. Though, perhaps this particular design was built to cater much more to the HT crowd rather than the music crowd. Seems silly to me though, that a driver and enclosure would be made with so much weight in one direction. Still not sure if that's actually the case here.

Sorry man I wasn't suggesting that your amplifier is defective, just that it is underpowered to begin with. And while Polk makes great high-value speakers, their subs leave a LOT to be desired. I do agree with others that the PSW110 is much better than some others like the PSW10, but it still isn't anything to write home about. And most subs in that price range are not very flat and are tuned too low. You may be able to improve the sound with some tweaking, but from experience the improvement will be minor at best. But hopefully you can prove me wrong. Good luck!

felipe

Looking at your room diagram, you could also try (if you can) putting it in between the right front speaker and the cabinet? It might yield better integration with the center and mains. I'm confident though that putting a rug-like mat underneath the sub will tame the boominess some .

tonyb

I would certainly try moving that sub on the flipside, other end of the front left. Did you mean the crossover on the sub was set at 100 ? If so, turn it up to it's highest value.

How are the settings in your bass management in the receiver ? Can you list some for us ? Are the speakers set to small or large ?

That room is kinda pushing the limits on what a sub that size can pressurize. Like we said, the DSW and Micro pro Polk subs are the sweet spot as far as Polk subs go. You'll find most here use different brands already mentioned for good reason.

You probably won't find many Monster cable fanboys here either, well....maybe a few but they've been banned to a small island in the North Atlantic. Try an Audioquest cable, you might be surprised.....or one from 100 or so other brands.