Axiom Home Page Forums General Discussion Home Theater Bass Management

I have a bass management question I could some input on. I’ve ordered the following speakers for a 5.1 HT system:
M22ti’s (freq. response of 60-22K Hz, +/-3dB),
VP100 (freq. response of 95-22K Hz, +/-3dB),
QS4’s (freq. response of 100-22K Hz. +/-3dB), and a
SVS PB10-ISD subwoofer

I don’t own a HT receiver like the HK’s whereby a different crossover point can be assigned to each speaker separately. So I have to use the same crossover point for all 5 speakers. I was wondering what crossover setting you would suggest in such a situation?

The two solutions that seem obvious to me, who’s never owned a subwoofer before and has a very limited knowledge of bass management strategies, are:
1. Set the mains to large and the centre and surrounds to small with a crossover of 80 or 100 Hz. It seems to me the downside of this option is while playing movies I’ll only hear LFE’s that are directed to the centre and surround speakers. Do movie sound tracks often have LFE’s unique to the mains, I don’t know? While playing music in 2 channel mode I won’t hear anything below the selected 80 or 100 Hz unless I change the setting for the mains to small each time I play music and back to large when watching movies.

2. Set all the speakers to small with a crossover of 80 or 100 Hz. If I recall correctly from what I’ve read doesn’t sound over about 75 Hz start to become fairly directional to the human ear? If that’s the case then with a crossover of 100 Hz wouldn’t imaging suffer during 2 channel music playback? If I go with a lower crossover (80 or 60 Hz), imaging would improve but then I’ll get a hole in the sound coming from the centre and surround speakers during movies.

Geez, it’s starting to sound to me like I’ll just have to change the crossover and/or large/small settings each time I switch between playing movies and music.

Of course two other options are to spend a bunch more money and replace my newly acquired receiver with an HK or upgrade the M22’s I’ve ordered to something like M60’s that have a lower frequency response. I’m already at my budget limit so I don’t really want to go there.

Again, any suggestions you could provide would be much appreciated.

Paul

Paul, I'd suggest option 2. with probably the 80Hz crossover. There really wouldn't be a "hole" created in the bass from the VP100 and QS4s, since the 80Hz crossover isn't a sharp cutoff and the PB10 would have some output above 80Hz. Of course also try 100Hz to see if you like it better. Any localization of the sub might not be significant even with the 100Hz crossover, but try and see.

Hi Paul

The answer? Separates! Yes, a processor and outboard amplification. You set the processor to LARGE for all speakers and run an Outlaw ICBM bass management unit between the processor and amps. You can then set the cross over for each channel separately. Two additional benefits - (1) you get stereo sub pre outs from the ICBM, and (2) you get bass management even when using SACD or DVD Audio (which usually bypasses the receiver/processor bass management functions.

John and 2x6, thanks for the suggestions.

I'll start with the the no-cost tweaking suggestions and see how satisfying a result I get. If I'm unhappy, then it's on to spending more $$.

Now if only the Axioms would arrive soon (the downside of penny pinching and ordering factory outlet stuff). The receiver and connects arrived the last two days, the sub is on its way and the Axoims are still 9 days from leaving the loading dock.

Oh well, gives me more time to learn and get some laughs from you all on this board.

Paul

My setup is similar to yours, except I have the VP150. My receiver has a fixed cross at 100hz, and there's some localization with music. I've wanted to try an ICBM for some time now, but there always seem to be more important things on the shopping list. Let us know what you end up going with.

Will do.

Paul

PaulM

sorry to change the topic, but how do you find your
SVS PB10-ISD subwoofer?

I was thinking about getting the same model.

In reply to:

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how do you find your SVS PB10-ISD subwoofer?

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Feel around on the floor until you encounter the big, rumbly thing?

Sorry. Couldn't resist.

Yes, Paul, please give us your impressions! There don't seem to be many reviews on that model yet.

Ravi, Tom

Once I get it (it just left SVS and has to cross the border ....) and play around with it for a while I'll let you know what I think. I won't have a lot of perspective to go by as the only other sub I've experience with is a Velodyne DLS-4000R (12"er, about the same value as the PB10) that I demo'd the last month or so.

I was so close to buying the HSU STF-2, but then I read the reviews by Ed Mullen on both the HSU and SVS. The lower response and slightly higher output of the SVS swayed me ever so slightly in their favour. The SVS is more limited in its application than the HSU as the amplifier lacks speaker level inputs and a low-pass filter. But since I plan to use it exclusively with an HT receiver, I figured I wouldn't need the versatility of the HSU (I hope time proves this true).

http://www.hometheaterforum.com/htforum/showthread.php?s=&threadid=209418

http://www.hometheaterhifi.com/volume_11_4/svs-pb10-subwoofer-10-2004.html

>>how do you find your SVS PB10-ISD subwoofer?<<

I wasn't asked, but since I have one myself I'll chime in. As I explained in my first thread the other day, I'm a newbie in the HT game so I can't explain things too well nor do I have a lot of experience to reference so please bear with me.

I recived my PB10 last Tuesday 3/22/05 and had a few hiccups in getting it set up, but kept at it for a few days & now believe I have it right. I don't own a SPL meter or calibration disk so I just used MCACC to do the calibrating. I found that it (MCACC)works as good as advertised, at least to my ears. Now, as to what you want to knwo about, the PB10, let me just say WOW!!! I spen't a good bit of time researching various subs and listening to what I could in various B&M stores, both boutique & big box, and I can say without reservation that this thing can hold it's own with Paradigms and Velodynes costing many times more. Again, I can't give you any numbers, only subjective impressions, but it is a truly brilliant product and I can't imagine anything at it's price point beating it, but to be fair, I haven't heard any Hsu subs (and almost bought one). If you get one, be prepared for how big the damn things is. Even though I read the dimensions on the website I still couldn't believe it when I saw it. The UPS man actually called me at work to ask if I was home and what to with it since I wasn't there to sign for it. He asked me if it was a TV and when I told him what it was all he said was "DAYUM!!!!", which is what I say every time I crank it up.

From what I've read on various forums, you can't go wrong with the PB10 or any comparable Hsu (or the Outlaw for that matter), but the conventional wisdom is that the Hsu is "more musical" while the PB10 is better with video LFE (more extension). That's not to say that the PB10 doesn't sound great on music, or that the Hsu is bad with video, but each has it's own characteristics, and these seem to be what most hold true.

FWIW I hope this helps some little bit and I am more than happy to answer any questions anyone may have about the sub as best I can.

Ron