Multiple subs increase extension?

[j_garcia]

Yes, but I guess what I was getting at is now you will likely hear 25Hz (or at least hear it better), where before it was considerably lower in ouput. I agree the dropoff is still there, but the increased output makes the lower frequencies more audible, though ultimate extension is not exactly improved, as the physical drop off point for the subs will remain the same without EQing.

I was running two subs recently and it was most notable at the lowest frequencies where the extra output was of use. The second sub was not identical though, and did not extend as low as my sub, so extension wasn't changed AFAIK, and I don't know that I would be able to tell anyway. I use a 14Hz subsonic filter on my sub.

 

[annunaki]

Yes, the 25hz output may be a bit louder/more audible than before. However, because the relationship in relative volume to the other frequencies has not changed, the difference would be minimal at best.

 

[Josuah]

Assuming you are doing the right thing, and calibrating the subwoofer signal level after adding the second sub, you will not in fact be hearing 25Hz as louder in output, unless your single sub was suffering from compression at your listening levels. In which case 25Hz might be -10dB at both 1W and 1000W, rather than -10dB at 1W and -15dB at 1000W.

 

[JimP]

Depends on the subwoofers.

The resulting change in extention will depend on the characteristics of the subwoofer. Some subwoofers response curves don't change regardless of SPL. Others have a significant drop in extention as the SPL is increased. Having two of the first sub wouldn't improve extention. Having two of the second one would as you wouldn't have to run them as high and you'd be in the part of the performance range where the extention doesn't drop off as rapidly.

 

[annunaki]

If one is eq'ing a subwoofer, be sure that, if ported/vented, that you are not boosting frequencies below the tuning of the enclosure. This could result in damage to the driver as a result of over excursion or burning of the coil. Most subs will include a very steep infrasonic/subsonic filter to try and eliminate this. However, some cheaper or DIY subs may not have that feature.

 

[kramskoi]

no additional extension...

and i learned this the hard way...yes you do get more output but the relationship between the upper bass and the lowest bass remains the same...

at whatever level you listen, 25 Hz would still be masked to the same degree as before...you simply get added spl/headroom which keeps the sound signature more coherent through less power compression, suspension/surround/coil hysteresis and THD...among many other things...

the improvement you'd hear would be more the result of a system not being constantly overdriven and falling prey to high VC temps and the consequent amplitude and phase distortions...

i think many enthusiasts drastically underestimate the kind of system that is needed for accurate, high level source-signal reproduction...

that said, putting a second driver in the same cabinet as first and increasing its size to an optimum alignment is a different matter...

 

[annunaki]

Yor 3-15" TC-3000 setup is quite impressive. WOW!

 

[kramskoi]

Yor 3-15" TC-3000 setup is quite impressive. WOW!

thanks...it can definitely hold its own...