Subwoofer feels underwhelming

[wardzin]

For my setup, I'm running my recently-acquired KEF R3 Metas with a WiiM Amp for (mainly electronic) music and home theatre use. And I'm absolutely loving them.

Now, subwoofers seem to be very hyped up in the audio community. From what I hear, they're considered to be a must and a game-changer (especially for bookshelf speakers), and they seem to increase the listener preference score by two whole points for nearly every speaker. So, I decided to get an SVS Micro 3000 for $1500 Canadian dollars.

Here are the measurements:

Seems like the sub maybe gives me an extra 15 Hz of low-end, and cleans up the room modes a little bit. Nice!

However, from a subjective listening standpoint, the upgrade feels underwhelming, to be honest. I keep toggling the sub output on the amp on and off to compare, and it feels like sometimes I can barely hear the difference. Drums and basslines feel a tad bit more "full", but only on some songs. It's not really the night-and-day difference I've been led to believe, and nowhere near worth the $1500 price tag.

I feel like this might be because the KEF R3 Metas already go pretty damn deep in my room, and the fact that they're close to the back wall certainly helps. Maybe for speakers that are more lacking in the bass department (like the KEF LS50's), the difference with a subwoofer would feel quite a bit more substantial.

Anyway, I'm still in the return period of the SVS Micro 3000, so I'm debating whether I should return it. Maybe my speakers that go deep enough, I don't really need the subwoofer?

Or maybe I'm doing something wrong. Has anyone else had a similar experience with subwoofers?

 

[MarkS]

The graphs look like you are doing nothing wrong. So if you are happy with the sound without the sub, I would advise returning it and saving the money.

My main speakers (small towers) also roll off sharply below 40 Hz, and so I too added the SVS 3000 Micro. I mostly listen to classical, and on certain orchestral tracks it is a noticeable subjective improvement in the power and weight. Having heard it, I would not give it up. But that's me, my main speakers, my room, and my musical preferences.

 

[Keith_W]

At the risk of sounding like a subjectivist, I will share two measurements with you.

Red = system configured as a 4 way, with subwoofer XO at 50Hz.
Green = system configured as a 3 way, with subwoofers removed, and woofers extended all the way down

These crossovers were created with Acourate DSP software, and are actual verification measurements of the filters. The reason the two filters look so similar is because the microphone was not moved between measurements. I can switch these filters back and forth by pushing a button on my convolver. The system is a 2.2, i.e. 2 main speakers and 2 subwoofers.

There is subjectively a massive difference between the sub vs. no sub configuration. In my system, the subs are placed in the corners to provide maximum reinforcement and Griesinger's stereo sub effect. Even though the frequency response is close to identical, the version with the sub sounds more full, more enveloping, has more impact, and subjectively wider soundstage.

I can not explain why it sounds this way even though the graphs are the same.

 

[sigbergaudio]

If your main speakers already goes to around 30-35hz inroom, depending on your taste in music you may not require much deeper bass.

But subwoofers isn't just about deeper bass, it's also about more even bass. What crossover do you have currently? If you crossover at 100hz, a graph like the one in red below seems realistic by employing a bit of EQ. That will probably give you a bigger perceived difference. You may still feel it's not worth it, but could be something to try.

 

[voodooless]

I keep toggling the sub output on the amp on and off to compare, and it feels like sometimes I can barely hear the difference.

This sounds like you are not high-passing the R3s? You should definitely do that at around 80 Hz. Pull down the peak at 90 Hz as well. There also seem to be differences above 100 Hz. Why is that? Is your subwoofer low pass too high?

 

[norman bates]

I'd be more worried about the dip 100-200hz.

 

[sigbergaudio]

I'd be more worried about the dip 100-200hz.

With regards to this, @wardzin, how far from the wall have you placed your R3s?

 

[Golf]

OK, I am totally inexperienced with subs as part of a 2-channel set. But how about temporarily disconnecting the two main speakers before listening to a well known tune – in order to see (well, hear) what the sub itself is actually doing?

 

[Geert]

What do you expect from a sub:

1. Extended low end? > Might not make lot of a difference if your main speakers already go pretty low.
2. Tackle room modes? > In this case don't high pass the main speakers. When possible, move the sub to where it makes the most difference.
3. Higher max volume with lower distortion? In this case high pass the speakers.

 

[GaryY]

In my primitive experience, one of the most important part is reasonable time alighment which makes sounds so called "punchier".

 

[Golf]

In my primitive experience, one of the most important part is reasonable time alighment which makes sounds so called "punchier".

Well ... Are there any 2.1 sets capable of tuning some sort of time alignment?

 

[Sokel]

In my primitive experience, one of the most important part is reasonable time alighment which makes sounds so called "punchier".

Punch is higher than subs range.
They might help freeing some mid-bass capability if the mains have a driver able to punch,but punch is mains task.
If they can't do it by their own sub will add some but not the punch expected from a generous mid-bass.

 

[GaryY]

Punch is higher than subs range.
They might help freeing some mid-bass capability if the mains have a driver able to punch,but punch is mains task.
If they can't do it by their own sub will add some but not the punch expected from a generous mid-bass.

Ah I see. Maybe at that time my setup of crossover was too high 130Hz. Now i changed to 60Hz. Thanks for instruction

 

[GaryY]

Well ... Are there any 2.1 sets capable of tuning some sort of time alignment?

It depends on your pre part I think..

 

[Matias]

It's the same reason I have not bothered adding a subwoofer in my system. Almost inaudible in my case too.

 

[boxerfan88]

Want punchier? Need to level up 40-150 area.

From OP’s chart, there seem to be a wide hole from 130-200Hz; and a deep hole in the important 60-70Hz zone.

Might wanna experiment with placement to mitigate some of those dips.

 

[bodhi]

However, from a subjective listening standpoint, the upgrade feels underwhelming, to be honest. I keep toggling the sub output on the amp on and off to compare, and it feels like sometimes I can barely hear the difference. Drums and basslines feel a tad bit more "full", but only on some songs. It's not really the night-and-day difference I've been led to believe, and nowhere near worth the $1500 price tag.

You might want to take any claimed "night and day" differences with a grain of salt from now on...

In my experience if the main speakers play pretty low, like the R3 does, and you don't have any gaping holes in FR that subs would fix then the improvement from sub(s) might be subtle. Not unlike what you are experiencing.

I have the R5s with quite a bit beefier sub setup currently and switching to 2.0 doesn't have that big effect with most music I listen to, with moderate volume. When I switch to movies and dial up the volume, then the differences is obvious.

 

[er|κzvio1in]

If you're listening at low to moderate volume, the threshold of audibility of those frequencies is a big factor. The effect of the added sub will be more pronounced at higher volumes because of our hearing. At higher volumes, your Kefs will also start compressing and distorting so you might want to high pass those. Also the subwoofer helps with more even distribution of bass. Btw it's quite impressive to see your graphs with deep extension of such small speakers, I run a 2.2 system myself, but my small speakers' roll off happens much higher and suffer from SBIR from the side walls and ceiling around 100 hz so my subs are crossed over at 100. I see you also have some peaks and valleys between 120-250.

 

[terryforsythe]

However, from a subjective listening standpoint, the upgrade feels underwhelming, to be honest.

In addition to the low frequency extension, the harmonic distortion and response linearity should be improved below 100 Hz or so with the crossover active. REW has a tab that shows the measured harmonic distortion. You might want to compare the harmonic distortion with and without the crossover active.

Here are Erin's measurements of the KEF R3 Meta, which includes harmonic distortion and response linearity measurements: https://www.erinsaudiocorner.com/loudspeakers/kef_r3_meta/

But, harmonic distortion in the low frequency range may not be that noticeable. If you don't hear a noticeable improvement, then return the subwoofer if you are able to.

EDIT: Also, see what it sounds like with the KEF ports plugged when you are using the subwoofer. On my Elac speakers this helped tighten up the bass in the mid-bass region, but some speakers may not work so well with the ports plugged. With the ports plugged I use a 100 Hz crossover frequency.

 

[ExPerfectionist]

Ah I see. Maybe at that time my setup of crossover was too high 130Hz. Now i changed to 60Hz. Thanks for instruction

Run measurements with different XO points engaged.

I have Sierra-LX and a Rythmik F12SE, and found that a crossover of 100Hz in the receiver produced the smoothest transition with the least amount of cancellation, even though the speakers could be crossed at a much lower frequency.

You may also be able to experiment with phase and/or sub distance to experiment and reduce the amount of cancellation in the crossover range, depending on the equipment you have and how bass management and distance, phase, etc. are handled.