Subwoofer recommendations

[Mr. Analog]

Hmm, it says on the spec that the new sub would be shielded.  Assuming it didn't warp my entertainment units top shelf, would it be safe to pu the sub on top of the entertainment unit, over the TV?

No way Jose, like Cova said  you are going to get a lot of movement out of it if you put it on a smooth, non-flat surface.



In your apartment I would place it in the corner by the window, it will fill the room nicely there.

[Melbosa]

4 subs, IMHO are overkill, even two subs is pushing it (I do find Mel's setup to be a bit bass heavy, no offence). Facing foreward firing subs opposite each other could have a cancelling effect or cause other serious distortion issues for other interacting speakers (notably rear surround channels).

True, that is why when you setup like this, its nice to have a seperate audio device to reduce and variant your audio specifically to your subs.  Yeah, I'll admit I like a little more base than some, but never do my subs over power my movies.



Q-sound is supposed to cause a similar effect on the omnidirectional stuff, but never found it really worked all that well.  Whether the channel's source is omnidirectional doesn't really have that large effect.



Again I'm not trying to convince anyone to use this setup, just giving an alternate angle to the whole subject.  I know this is way out of Ustauk's line of purchasing, even my own at the moment - just so happened that I had most of the pieces to make this work sitting around.



Alternately, I find the sub that Mr. Analog has, as well as some of my other friends not on these boards, to be insufficient to my thinking for the home theatre experience.  I just think that in order to make it work, you have to buy a sub like you buy a centre channel - they should be the most expensive speakers you own, but that is just my opinion.

[Thorin]

I agree that the specs were pretty close. The only differences were the size, and something called power handling, which is 260w  on the polk versus a 150 watt.  Does anybody know what power handling means?  And the Polk has a three year warranty on the electronics, where the JBL only has a 1 year on the electroincs.  Both have five on the speaker.

Power Handling as Futureshop is referring to it there is indicative of what kind of power the speaker can handle without being overdriven.  As you can see from the stats they list, the amplifier and speaker are matched in power output and power handling.  Go figure, it's almost like they planned it, eh?



By the way, I found more detailed specs on www.polkaudio.com.  Reading the customer reviews, there's a few people who complain about port noise.  This is typical with front-firing front-ported designs.  I assume it's not as noticeable with the grill on, or if you move it further away from where you sit (like in the corner as Cova and Mr. A. both suggested).



Subwoofer cones move lots, so you need to put them on the most solid flat surface you have.  This is typically the floor, although if you have a concrete or brick entertainment unit that'd be fine, too.

[Shayne]

Remember, its better to over power a sub with "clean power" then it is to under power it.  Curtis was sending 1000W RMS to his 10" JLs...sure they moved a good couple inches when driving hard, but ran hard, and ran well.

[Mr. Analog]

Alternately, I find the sub that Mr. Analog has ... to be insufficient to my thinking for the home theatre experience.

Personally, I find it well balanced when I turn it up, which I usually do not as I live in a human hive. Alternativly, everyone has their own sense of "what sounds good", on my current setup I can hear sound effects, dialogue and musical subtleties with equal clarity.



Regardless of componentry, I reckon just about anything can sound good if configured with care.

[Thorin]

Remember, its better to over power a sub with "clean power" then it is to under power it.  Curtis was sending 1000W RMS to his 10" JLs...sure they moved a good couple inches when driving hard, but ran hard, and ran well.

Couple of notes there:



1. Underpowering is a myth.  Sending only 10 watts to a speaker than can handle up to 1000 watts will not harm it.  Humans who try to crank the gain on the amp and the volume on the receiver until the sound signal has audible distortion will destroy a sub, but then it's the distortion, not the low power, that destroys it.



2. 1000 watts RMS, from what make and model of amplifier to how many of what model of 10" JL Audio subs in what arrangement and what kind of enclosure?  With a strong enough amplifier and a weak enough speaker, you can rip the cone of the speaker out of the basket.  I've seen it done.  Usually, right after the cone rips out the voice coil will touch the magnet and weld to it.  At which point you have a blown speaker, although the root cause is physical failure.



It seems this simple request for subwoofer recommendations has turned into quite a thread

[Ustauk]

The amp power on the JBL was 250 watss, while the power handling was 150 watts.  This was one of the few differences between it and the Polk.  Because of the difference between amp power and power handling, would it have been easier to blow?

[Thorin]

The amp power on the JBL was 250 watss, while the power handling was 150 watts.  This was one of the few differences between it and the Polk.  Because of the difference between amp power and power handling, would it have been easier to blow?

You're quoting these figures from the Futureshop website?  They're notoriously inaccurate.  Believe me when I say that even low-end JBL house subwoofers with built-in amplifiers have speakers and amplifiers that are matched to each other.



That said, there's RMS power (also called "continuous"), and peak power (also called "maximum" or, these days, "dynamic").  For both the Polk Audio and the JBL the wattage listed by Futureshop will be the peak power.  I'm willing to bet that the RMS power for both is 100 watts.  For the Polk Audio, you can see that on the specifications page.



But I want to reiterate here:

- Futureshop stats are notoriously inaccurate

- Respected house subwoofer manufacturers choose the right speaker and amplifier and balance them to each other; it costs them nothing extra to do so, and not doing so can cause lots of bad press



Which makes me wonder about your previous Polk Audio sub not working anymore...  You said there was a hum and if you wiggled a wire it went away; I suspect there was either some minor short in the amplifier circuitry or the audio signal cable was picking up a large amount of noise.  The hum might have been low-volume distortion, and eventually distortion will cause a speaker to fail, usually by having the voice coil touch the magnet dipole and weld to it.

[Ustauk]

All right Thorin, you convinced me.  I changed my order to the JBL 10", at $287 versus the $445 Future Shop price.  It's not quite as good a price difference, but I really should try a different brand after the Polk died on me, and your recommendation convinced me.  The JBL won't be coming in until next week, so I'll let you know then how it goes.

[Thorin]

I found specs for the JBL E150P on www.jbl.com.  If that is the correct subwoofer, then you have switched to a non-ported sub, from what I can see, which would eliminate the possibility of port whistle (always a good thing).



Also, if you look at Polk Audio's ratings from their site (posted earlier) versus JBL's rating, the continuous power is only 100 watts into the 12" as opposed to 150 watts into the 10".  Smaller cones produce less decibels (dB) of sound pressure level (SPL or dBSPL).  Higher continuous power ratings increase production of dBSPL, so long as the speaker wasn't already at its limit.



The 2" loss of cone diameter will be offset by the 50% increase in wattage.  If you were to listen to these two subs side by side in a store, or even with an SPL meter, you would probably see 1dB or less difference.  1dB is the minimum change in sound pressure level the human ear can determine.



So then it comes down to how they sound; ported subs are boomier at the frequency their port is tuned for, closed-box subs are flatter in overall response.  Basically, ported subs are more specialized, closed-box subs are more generic.  Me, I prefer closed-box subs but ended up getting a ported sub for home.  Still sounds just fine.



I'm sure you'll be happy with your purchase, especially once you get the crossover cut-off frequency and the level adjusted just right - the manual explains how and why to do this.

[Melbosa]

When talking in terms of Cars, ported boxes cater more to the dance and trance (rumble more) vs the enclosed ones are better all around (punch more) and sound good with most music. I think the same can be said for the home stereo market.

[Ustauk]

I had the polk sub on a the coffee tablish piece of furniture with two cabinest built into it.  I think I'll put the new one there, but I'll turn it to face the entertainment unit right next to it, and see how that works.  I don't want to face it backwards since that would point it at my neighbours apartment, and even with him being hard of hearing, hi might notice the throbbing bass through the wall  Does anyone want my old sub for dissection?  It the speaker may be fried, as Thorin suggested, but it could be the electronics are what's fried.  And I don't think there are any cracks in the cabinet.  First come, first serve.

[Mr. Analog]

Don't you have concrete walls?

[Ustauk]

Don't you have concrete walls?

My bedroom wall is concrete.  My living room/dining room wall sounds a bit hollow when I tap on it, so I think its not concrete, unless there is some space between the drywall and the concrete. My floor an ceiling are both concrete.  Having watched a few concrete towers go up around downtown in the last few years, it seems common to have concrete outer walls, floor/ceilings, and support pillars, but the rest is metal framed drywall.  So you still get some noise, even on the newer buildings.

[Thorin]

I had the polk sub on a the coffee tablish piece of furniture with two cabinest built into it.  I think I'll put the new one there, but I'll turn it to face the entertainment unit right next to it, and see how that works.  I don't want to face it backwards since that would point it at my neighbours apartment

The best place for the sub is on the strongest, flattest, most inflexible surface.  In houses this is typically the floor.  If that piece of furniture really doesn't bend at all when you push on it with all your might, it *might* work.  You might still hear a rattling noise and/or see your subwoofer moving (and thus eventually falling off the furniture) when you turn it up loud.



The suggestion to face it at the wall was to try and diffuse the sound to make it less directional, and thus make it seem more like it's part of the front soundstage.  However, this would make a small difference, not a large difference.  Then again, a bunch of small differences result in a large difference, usually