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managuense
12-08-2003, 10:19 AM
About 5 months ago i purchased a B&W asw600 sub (10inch driver 150w amp), along with 602s3s, lcr60s3, and 600s3's. Everything is fine except the sub. Well not exactly, the sub performs well, but does not go low enough nor does it have the punch in the stomach that I desire for HT. In addition it seems to have a faint rattle during heavy scenes.
Increasingly I am thinking of using my 1 year trade in at my shop, the subwoofer brands they carry are B&W, Velodyne, Definitive technology, Klipsch, and M&K. What I am looking for is a sub that will give me the punch that we all love for HT. What I am worried about is replacing a very solid, extremely well made sub that sounds extremely good in most cases with a sub of poor quality that just spits out noise.
My question is has anyone had any similar experiences with B&W subs versus the above mentioned other brands?
BTW I paid 450 +tax for the B&W and am looking to pay up to 7-800 for a new sub.
Thanks in advance.

zapr
12-08-2003, 05:55 PM
How do you have your sub connected and where did you put it?

zapr
12-08-2003, 06:00 PM
........also, did you play with the settings?The rattle you discribe could be something else such as your windows,walls,wall hangings etc.

managuense
12-08-2003, 08:37 PM
Ohh, I have it hooked up through the LFE, and the rattle is definately coming from the sub. It's not a huge rattle, just a little something that has me concerned.

mtrycraft
12-08-2003, 09:15 PM
About 5 months ago i purchased a B&W asw600 sub (10inch driver 150w amp), along with 602s3s, lcr60s3, and 600s3's. Everything is fine except the sub. Well not exactly, the sub performs well, but does not go low enough nor does it have the punch in the stomach that I desire for HT. In addition it seems to have a faint rattle during heavy scenes.
Increasingly I am thinking of using my 1 year trade in at my shop, the subwoofer brands they carry are B&W, Velodyne, Definitive technology, Klipsch, and M&K. What I am looking for is a sub that will give me the punch that we all love for HT. What I am worried about is replacing a very solid, extremely well made sub that sounds extremely good in most cases with a sub of poor quality that just spits out noise.
My question is has anyone had any similar experiences with B&W subs versus the above mentioned other brands?
BTW I paid 450 +tax for the B&W and am looking to pay up to 7-800 for a new sub.
Thanks in advance.


The Sep 2003 Sound & Vision rates 10 subs. B&W 675 is rated with a 500 watt amp. I am sure it is different from the 600.

You may want to consider a SV S sub?

Woochifer
12-08-2003, 10:03 PM
That particular B&W model is a sealed design (one of the few options of that kind in the sub-$500 range), which means that the bass will potentially extend lower than the more common ported designs. It also means that the lower frequency dropoff will begin sooner, but that dropoff will occur more gradually. In a nutshell, a sealed subwoofer theoretically gives you deeper bass extension but the sound gets softer sooner.

A similarly designed ported subwoofer will have higher bass output up to the port frequency, and then drop off very rapidly thereafter. Subjectively, a lot of people like to generalize that sealed designs are more well suited for music than home theatre because that more gradual dropoff in the bass response at the lower end is more natural sounding. Generally, ported designs will give you higher SPL output because they are more efficient, but they are also more difficult to design correctly because the port opening and the interior volume need to correspond. If impact with home theatre explosions are what you want, a ported design might give you of that visceral grunt. But, the tradeoff is that it might not sound as tight if it's not done correctly.

It could very well be that your subwoofer's not designed to deliver the kind of bass that you want. However, I would try a few optimizing steps before you go trading in your subwoofer. First of all, where you place the subwoofer makes a huge difference. Corner placements will reinforce the bass and give you the most SPL output.

Also, you should get a SPL meter and measure the bass output using the wideband test tone on your receiver. Make sure that the levels match the mains (and a lot of other subwoofer experts on this board recommend a level 4 db higher than the mains).

In addition to using a wideband test tone to measure the overall level, I would invest in a test tone CD and do some measurements at specific frequencies. That way, you'll identify where and if you have severe peaks and/or nulls, and these are more a consequence of your room acoustics than the subwoofer itself. If you find that your room is causing nulls to occur from your listening position, then you need to move the subwoofer somewhere else, preferably into a corner, because the waves are cancelling each other out at that precise location.

If you find large peaks, then that's causing boominess and bloated sounding bass, rather than bass that's full and even sounding. The way to correct these peaks is through either bass traps in the corners of your room or using a parametric equalizer, such as the $120 Behringer Feedback Destroyer. I use a parametric EQ and it was very effective at eliminating the peaking that I got with my subwoofer (also a sealed design). After making the corrections, the bass now sounds very well integrated, but with the deep impact intact.

If you trade in your sub for a larger ported model, I would definitely get the parametric EQ anyway because the more output you get in the lower octaves, the more likelihood that you'll run into a major room induced peak.

managuense
12-08-2003, 10:32 PM
Ahh thanks for the replies. I understand what you are saying woodchifer about the ported verses sealed design, the salesperson explained that to me. Well i dont really understand it thoroughly but i understand the end result. Will definately look into an spl meter, and as for room placement that will be difficult, maybe I'll try to move it a few feet in either direction but that is best i can do. From reading these forums for awhile I am beginning to understand the importance of placement.
As for one of the above poster, I did read the s&V article and these are two pretty different subs )asw 675 vs 600). Something I did discover in that article is the A/B switch on the back of the sub which is the same as mine. The salesperson explained it to me, it went right over my head, and the manual was pretty vague about it. Today i switched it to the A setting, which according to the S&V article (about the 675) allows for lower bass frequency levels but at lower output. First movie i watched seemed to be a great improvement. Out of curiosity does anyone else know anything further about this switch? I assume A might be good for movies, B good for music?
Anyways thanks again everyone, and woodchifer especially with his "subwoofer setup for dummies" reply.

Woochifer
12-09-2003, 01:23 PM
Something I did discover in that article is the A/B switch on the back of the sub which is the same as mine. The salesperson explained it to me, it went right over my head, and the manual was pretty vague about it. Today i switched it to the A setting, which according to the S&V article (about the 675) allows for lower bass frequency levels but at lower output. First movie i watched seemed to be a great improvement. Out of curiosity does anyone else know anything further about this switch? I assume A might be good for movies, B good for music?
Anyways thanks again everyone, and woodchifer especially with his "subwoofer setup for dummies" reply.

That sounds very similar to what Hsu includes in their subwoofers, but those are ported designs and the switch on those subwoofers is used in conjunction with a port plug to give you a choice between higher SPL output/higher cutoff frequency or lower SPL output/lower cutoff frequency. Never seen anything like this with a sealed sub before. From the way you're describing, the A position would be more for use with music because it extends the bass deeper while reducing the maximum SPL, whereas the B switch would be more for home theatre because it allows for higher SPL output. Regardless of intent, just go with whatever sound is better suited for your listening. Sounds like you enjoy the deeper response with your current position. A SPL meter will help a lot with helping you set the level on your subwoofer.

zapr
12-09-2003, 06:11 PM
Ohh, I have it hooked up through the LFE, and the rattle is definately coming from the sub. It's not a huge rattle, just a little something that has me concerned.
The rattle could be something as miner as a loose screw or more on the driver.Not overly loose but not tight enough to hold it securely when you turn it up.Did you use a y adapter on your sub out?

frankfalconi
12-09-2003, 08:23 PM
I’m also looking for a new sub, my main criteria is musicality and flexibility. It doesn’t matter how good a sub is, if it cannot integrate perfectly with the rest of your system, it will not sound correct. Fortunately for us most powered subs out there offer enough flexibility for proper integration. The musicality part is a little hard to come by though. One of the best sounding sub I’ve heard is the FHT-Sub from Sound Philosophy Acoustics. I stumbled in their room at Le Festival Son & Image in Montreal a couple of years ago. Check out their site at www.soundphilosophy.com. The impression that I had with the sub was echoed by one happy customer in their ‘testimonials page’, "I picked up the FHT-S from the Post Office this morning, and everything was in perfect condition, no damage. I LOVE THIS SUB! I'm glad I didn't waste a lot of money on some big Velodyne.-------Tight, articulate, deep bass. Who could want more, Not me! I'm sure as the Sub breaks in it will sound even better, although I can't imagine it sounding any better. It has integrated perfectly with the rest of my system, which I think I could lease out to Air Canada Centre if I wanted. At any rate I'm very happy and Thank You Very Much. I'm always buying speakers, so maybe I'll consider one of your models for my next purchase."... Anyway hope this helps.

managuense
12-09-2003, 09:08 PM
Like i said earlier the sub sounds really good, it totally disappears when I am playing music or movies. Being somewhat new to HT I think this is a good thing? It puts out a good amount of bass, which you can hear and feel, yet the sound is subtle enough so that my ears are tricked into thinking the bass is coming from my 602's. The more i listen and read these forums the more I am beginning to appreciate this sub, I really do enjoy it very much.

One thing that popped into my head is that since the B&W 600 series speakers are somewhat innefficient maybe I am turning the volume up a little higher than I would with other speakers without correpondingly turning down the sub volume? Does this make sense? Maybe I am stressing the sub a little too much?

Am i using a Y adapter? I am using a single subwoofer cable hooked up through the sub out on my Denon receiver (that's LFE right?).

As for other sub choices, I am limited to B&W, Velo, Def Tech, MK, and Klipsch for my store trade -up.

In the end I probably will trade up to the 650 which has a 12" driver but otherwise I think a similar, although somewhat larger sound.

Again thank you everyone who responded I appeciate it a ton.

Bryan
12-10-2003, 06:22 AM
Have you calibrated the sub as of yet using a SPL meter and calibration DVD? Second question is have you contacted B&W about the rattle to see what they recommend you doing? Next question: What size room is the sub located in? Any openings into hallways or other rooms and, if so, what size (dimensions) are they?

It is possible you have too much room for the sub. If that is the case, adding a second sub should solve the problem. If you do that, add a sub such as the SVS 20-39PC+, and send everything below 35Hz to it.

GOIRISH
12-10-2003, 08:28 AM
I bought the B&W 604 S3, LCR600 S3 & ASW675 before Thanksgiving. I think the ASW675 is great for music and movies; definitely feel the punch during movies. Try it out. The guy at the stereo shop had a $110,000 setup and he was using 2 ASW675 subs in the setup....Paul

GaToy
12-10-2003, 12:09 PM
If oyu do decide to trade in your sub, i'd suggest the Velodyne. It's a little pricey. But it sounds great. Me, i'm holding out for a Sunfire. I heard one in one of the local shops and fell in love.

~C.C.~

managuense
12-10-2003, 01:49 PM
Just back from the shop. I listened in to another customer testing out a big bucks sunfire and an 18 inch velodyne. All i can say is wow....maybe in a few years.

Also listened to a B&W 675 and was very impressed. It's amazing what such a small sub can do, it was hitting notes that my 600 can't even touch and was literally rattleing the walls of the room. Will probably place my order for it tomorrow.

The salesman also told me that in no way whatsoever should my sub be making any distortion in any scene in any movie. He suggested that it is probably due to a failure in the driver or the cabinet and fully covered under the warranty.

Thanks again, hopefully i can post an update in a week or so when and if i can get it set up.

GOIRISH
12-10-2003, 04:23 PM
I hear ya, when I was buying the ASW675 the sales guy also had Velodyne Servo??? controlled subs. Awesome stuff but very expensive; some day down the line will definitely upgrade to one of those Servo Subs.....Paul