Axiom Home Page Forums General Discussion Technical Questions two way multiple sub system

Most likely due to the fact the lower notes overshadow the higher frequencies, making it harder to hear the mid - upper bass range, especially if the room is sucking out some midbass etc. all the while emphasizing a lower range.


For the samre reason I noted above.

This can be perceived for a variety of reasons and it has nothing to do with the smaller bass drivers being tighter and more well defined.

1) A poorly designed subwoofer.
2) A well designed subwoofer that is not properly calibrated or running "hot".
3) Improper crossover integration between the subwoofer and the main speakers when set to small.
4) Placement issues. Some have found this "boomy", "flabby" characteristic to occur from corner loading a sub for example.

Here is another article on this topic that you might find interesting as well. It is from Alan Lofft of Axiom audio.

http://www.axiomaudio.com/tightbass.html

Wow, there has been a lot of good information from all to help me clear this up. Alan's article hit the nail on the head with this issue and I am completely convinced. The first link was also very good, but quite technical. The "flabby", "loose" bass myth is almost as bad as the need for ultra expensive cables (speaker cable, HDMI, etc.) myth. It seems that to choose the correct sub you just have to narrow it down to good sub companies like: Axiom, Hsu, Outlaw, SVS, etc. Once you settle on the brand just make sure that you choose one (or preferably two) large enough to fill your listening area. That's it.

Jay hit the nail on the head for why I’ve preferred my M80s alone for music just look at the before curve:

http://www.axiomaudio.com/boards/ubbthreads.php?ubb=showflat&Number=307389&fpart=1

Even though the curve for the M80s is going to be no better, w/o the big low bass hump overpowering everything else the M80 come out sounding “tighter” and “clearer.” It’s also why I’ve often run my M80s using “double bass” or “LFE + Mains” to get some smoothing from having multiple bass sources even though they are not optimally placed for that purpose.

I'll wager that at least half of those that find the bass from their mains 'quicker' do so because someeone told them they should.

The other half probably benefit from in room placement of the mains giving them better upper bass than wherever they put the sub.

The other reason one might have 'slow' bass from a sub is if the driver is marginal and has been optimized for bottom end performance at the sacrifice of upper end dynamics.

I have modeled a 10" driver where I could get good output down to 17Hz, but the trade off was that the driver started to roll off noticably above 80 Hz. Changing the tuning so that the low end roll off was at 25Hz restored the top end.

On the other hand, if you use a monster driver like the Exodos Mal-X 18 you have enough excursion for sub 15Hz performance, but have enough power handling and a well enough designed driver that you do not loose anything at the top end.

I think that this is why Axioms subs sound so good with music. Nothing is sacrificed in the upper bass to get more low end distortion.

If you are really curious about stuff like this, go over to avsforum.com and search the DIY speakers & subs forum for user Mark Seaton. He has made a number of excellent posts where he talks about sub desing and tradeoffs.

Yes, Doc; thanks for linking Alan's excellent article which covers these points very well. Ian's observation about how a sub crossed over higher might sound "tighter" simply because it was playing "tighter" higher frequencies was quite interesting.

He has a small company that makes Seaton Submersive subs that he designed right. Everybody talks about them and how great they are, but you can't find much info, like pictures, frequency response, etc. I know that they are supposed to have dual opposing 15" drivers in a box and that's about it.

IIRC, Seton was regarded as THE man for subs by those on av123 and I beleive he is/was helping Craig with some stuff at TCA.

Mark Seaton has cut ties with AV123 as well as TCA from what I understand. He doesn't develop any products for AV123 anymore and never developed anything for TCA. He has his own company of course which is pushing out product.

I knew I had read that Mark was going to be involved, look up the Sasquatch 18? thread...........

Never mind

http://www.tweakcityaudio.com/forum/showthread.php?t=71