Small or large sub for music


I've been using a pair of Velodyne HGS-10s to supplement KEF LS50s below 50 Hz, but I read that larger subs are better for music because the cone needs excursion.  Is there any truth to this?  I have a pair of HGS-15s that I could use to supplement the LS50s or Reference 1s (below 40 Hz) if I go there.  The HGS-15s do HT superbly.

db
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I've been in the actual music biz for over 5 decades...back when we used Altec A7s (extremely efficient) we typically ran maybe 200 watts into the bass speakers and 50 to 100 into the horns to make things balanced. Now I use 1500 watt powered bass systems, with maybe 350 watts per side for full range main speakers. Look at meters for output on home gear and you get the story...bass frequencies take up a lot of juice, even with efficient speakers...they simply do.
For one thing we’re discussing subs, not full range. For another thing the reason you need a lot of power for many speakers to produce bass is that they are 3 dB or 6 dB or 9dB down at very low frequencies. Many speakers are more than 9 dB down 25 Hz. Which is why you sometimes need a sub in the first place. Hel-loo! If you need a lot of power to get decent bass you’re doing it all wrong. This ain’t rocket science, folks. 🚀

@wolf_garcia wrote: "I’ve been in the actual music biz for over 5 decades...back when we used Altec A7s (extremely efficient) we typically ran maybe 200 watts into the bass speakers and 50 to 100 into the horns to make things balanced. Now I use 1500 watt powered bass systems, with maybe 350 watts per side for full range main speakers. Look at meters for output on home gear and you get the story...bass frequencies take up a lot of juice, even with efficient speakers...they simply do."

I think I see where our disconnect lies. I think you and I are mis-communicating.

You’re saying that you have observed amplifying (or reproducing) bass takes more power than reproducing the rest of the spectrum, and I’ve been saying that if a speaker has a flat frequency response, by definition the same power input produces the same SPL output up and down the spectrum (including in the bass region).

I think we are both right. What we are missing is, equal-loudness curves. I think they will explain why the needle jumps on the drum hits.

In order for the fundamental of the kick (ballpark 50 Hz) to be perceived as being as loud as the electric guitars, its actual SPL must be MUCH higher, like about 20 dB higher!

That 20 dB peak for the kickdrum’s fundamental would call for a 100-fold increase in power over what the guitar needs (assuming the speaker’s efficiency is the same at 50 Hz as in the mids and low treble). In other words, the kick must be LOUD for its fundamental to come through with authority!  THAT is why the needles jump!

My numbers may be off a bit - the kick’s fundamental is probably not as loud as the guitars - but I think the principle is valid, and I think it explains the apparent discrepancy between what you and I have been saying.

Duke