More Bass

@steakster - @mike_in_nc 

OK, how about 2 subs on the opposite wall 20' away facing the back of the listening position? 

>> OK, how about 2 subs on the opposite wall 20’ away facing the back of the listening position? <<

More likely to help than placement right by the speakers. You’ll never really know unless you measure. We all think we have golden ears, but I for one find measurements more reliable than my ears, in that they don’t change from day to day. But I admit, I fine tune everything by ear -- after getting the basic setup right by measuring.

@erik_squires - Hi Erik, so I asked this directly of Legacy:

What is the minimum impedance of the Signature speaker, is it 2 ohms below 100 Hz?

Their response: "The signature line can go as low as 3.5 ohms"

So, pardon my ignorance, but what does all this mean? Thanks!

Welp, there’s a number of published measurements showing this to be optimistic. As I noted elsehwere, I’ve found a couple of different models shown to be around 2 Ohms for most of the bass. This includes the SE and 20/20. Perhaps I’m misinterpreting the statement or the charts?

For any speaker that goes down this low it means that with many amplifiers the bass output will often be depressed relative to the rest of the range. See the separate thread on the KEF Reference 1 standmount which has exactly this issue.

The solution is a high-current amplifier of which there are many at various price points, but your average integrated amplifier probably wont’ cut it. For sure, almost no tube amp will work here.

At 2 Ohms, an amplifier has to produce 2x the current (Amps) as at 4 Ohms, and 4x the current needed at 8 Ohms.

If I were to guess I would say you are clipping your amplifier. 4 Ohm speakers will surprise you with how much power you need to get the bass to rumble...

I would have thought with the 7" woofers and a rated frequency response of 22-30K Hz, there would have been a bit more bass

Mr. Yachts,

You mention that you thought there should be a bit more bass, does this mean that the bass is non-existent or just not as loud as you expected it to be?  What are you trying to achieve, the more balanced bass that happens with classical and acoustic jazz or the chest thumping bass that you get with loud rock?

(although there is a couple of tunes I have played where there is some bass that is really deep and sounds all garbled,

I find this to be a troubling statement. The fact that you have played some songs that reproduced low bass, points a finger at the source material. Not all recordings were recorded well, especially pop/rock recorded prior to 1975 and the better your system the more this becomes apparent, but the fact that it sounded garbled would indicate that there is some kind of malfunction. There are a few things that would explain non-existent bass such as a room nulls, bad source material or out of phase wiring, but not the garbled sound. Is it possible one or more of the 10” drivers is not functioning properly? If you place your finger tips on the cone of each driver and push do they move easily? If there is a scraping sound or the driver does not move at all that would indicate a blown speaker. There also might possibly be a failing component in the crossover.

We have had Whisper, Focus, and Signature on site. I found that the Sigs were more balanced. They had good bass but not overpowering.

This statement leads me to believe that your amp is not part of the problem, but I don’t know if you mentioned to them the garbled tunes?

This tune “Flight of the Cosmic Hippo” by Bela Flack has some very low bass. If you can stream it or find a copy to play, please report back on how it sounded.

Also, the speakers could have accidentally been wired out of phase inside the cabinet by the manufacturer.