Selecting an Appropriate Sub

[bigburner]

I run a pair of CDM9NT speakers powered by a Rotel RB-1080 amp (200 watts RMS per channel) fed by a Rotel RC-1070 preamp. I want more bass for certain occasions and am therefore contemplating buying an active subwoofer. I’d welcome advice on subs in general and recommendations on an appropriate B&W sub that would match my current system well. Specifically:

* Are subs well suited to systems which don’t have the functionality to offload bass to the sub the way that HT systems can, or do you really need an HT system to get the best out of your sub? For example, I’d like to reduce the bass load on the CDM9NTs. Is this possible with a non-HT system, using the smarts built into the sub?

* Are there any rules of thumb when selecting a sub, such as the power of the sub compared to your main amp, crossover functionality, frequency range of your main speakers, speaker size related to size of room etc, or do you simply buy the best one you can afford? For example, from reading this forum the ASW850 sounds wonderful but would surely be overkill for my system and budget? An ASW650 or 675 appears to be the level I should be aiming at. Am I in the right ballpark?

* Taking your recommendation from the previous question, is B&W the best choice in this price range or should I be looking at other vendors too? I’m obviously a B&W supporter for main speakers but I don’t know enough about their subs to appreciate whether that’s B&W’s strength. For example, SVS keeps popping up in this forum. My Rotel dealer is recommending Mirage subs; has anyone tried them?

[wsung23]

It's better to use a sub for surround movie or music if you don't use same full range speakers for front, center, and surround speakers (at least I can't find enough space to place 5 large speakers). To get balanced bass output, a sub is perfect for that purpose.

I have used a discountinued sub (ASW1000), although it only uses a 120w integrated amplifier, outputed bass is large enough, even it exceeds my demand, when I consider I shouldn't let my neighbours be furious due to bass penetrates solid pretty well. Personally I don't know where I can use those subs with 500w or 1000w output power (such as ASW800 series or ASW700 series).

Amplifier which can generate continous same power is also important for sub, amplifier in my ASW1000 can't. When I use sound pressure meter to measure pink noise from that subwoofer, I find SBL flucturates in 10db range. As a result, if only those super expensive subs (such as ASW800 series) can generate stable output power, I rather to buy a cheap amplifier but with good quality (for example, those small companies like musical fidelity produce some cheap one-channel amplifier) to drive a cheap B&W subwoofer.

[PewterTA]

There's also better subs from other manufactures that you will probably pay less for than the B&W subs, and get more performance.

If you are looking for musicality, HSU makes great subs. They work very well for HT use as well, but are definitely better suited for music. SVS also makes great subs and they shine in HT use, get the deep tones that the HSU doesn't do as well, they are good musically, but not as good as HSU. Both will blend in seemlessly with any B&W speaker.

The way you will want to hook them up is to use the Hi pass to the sub, then from the sub to your speakers, this way the crossover in the sub will control the lower frequencies and send anything above that point (ie 40, 60, 80 Hz) to your speakers. This will stop the sub and speaker from playing the same tones.

[Stevebez]

Guess this is somewhat of a personal choice and taste - but subs are becoming more mainstream especially given that movie output (i.e. the .1 is specifically produced for them).

This is finding its way more and more into music soundtracks. Allot of music written today has intensive and low bass - mostly because more and more people have the equipment to reproduce it.

To get sub 25hz from a floorstander is tough ... a good sub will do this with relatively ease. The better ones will get down to 15hz - but this is generally only good for rattling windows etc...

I think it has been a taboo in the past to listen to music in anything but stereo without a sub. I think this is slowly changing where more and more listen firstly to music in 2 channel + sub ... and then the more avant garde listen in 5.1 where available. For example some DVD-Audio discs have the 5.1 sound tracks as well which - in some instances sound fabulous - but also a little strange ??? ... You are in the middle of the sound stage rather than perceiving it as a picture in front of you.

Some people like this some not ...

Now in the end I cannot picture a system without a sub. Even for music. Although I have to say I am on the fence on 5.1 or 2.1 for music at mom ... but I use 2.1 currently only becuase my fronts are superb - maybe if I had better srrounds I would be more convinced. Also some subs are very good for music and some not... I would have to say - for music you better off with a great sub or if you cannot afford it rather have nothing. A bad sub with music is, well, just horrible. Save it for movies if you have to.

I like REL & Velodyne ...had a REL Quake and for its price and size it can be a welcome addition for movies - but not low or tight enough for music. I recently got a Velodyne DD-12, which is among the best ... very tight and completes the sonic picture of my 803D's superbly - particularly for music.

Your mileage, however, will vary ...

Rgds Steve.