Why the fuss with subwoofer specs and brands?

[bodhi]

If you perform this test, and you're happy with the result, then you don't need more sub power. But there IS a use for large subs, if you want a true full range system that is dead flat to 20hz you probably need 2+ good sized subs. Unless your room is super tiny.

One could also get couple KEF KF92. They are tiny

 

[Sancus]

One could also get couple KEF KF92. They are tiny

Sure and they have the same capability of any decent subs their size. There's absolutely nothing special about them.

 

[sarumbear]

I have something like 3000 movies on disk or on my NAS. I doubt more than half a dozen of them even activate my subwoofer let alone would be compromised if I didn't have one. I've never understood the need to differentiate between movies and music in this respect. All audio can benefit from a subwoofer to be accurately reproduced, but my sub certainly gets far more exercise on music listening than movie/tv watching. If a movie is only engaging with overblown crash bang effects then it's probably not worth watching anyway. Hardly a justification to get subwoofer ...

In a film soundtrack a subwoofer is fed by the LFE channel. It is short for Low Frequency Effects. No effects, no sub output.

 

[bodhi]

Sure and they have the same capability of any decent subs their size. There's absolutely nothing special about them.

Might be. I tested the 1723 1S against one KF92. I sent the Arendal back and got another KF92.

 

[jsilvela]

If you perform this test, and you're happy with the result, then you don't need more sub power. But there IS a use for large subs, if you want a true full range system that is dead flat to 20hz you probably need 2+ good sized subs. Unless your room is super tiny.

My system is linked in my signature, but just for completeness: I have 2x Arendal 1723 2S optimized with MSO and Audyssey. These are fairly large(not huge) sealed subs each with 2 opposed 13.8" drivers and 1200W. My space is relatively small, it's an 1100sqft 2bed apartment, the living area is ~500-600sqft.

This is brilliant, thank you!
It is the kind of information that I wish was given, rather than disparaging remarks on size/number/brand.
You need to have a measurement mic and a program like REW, though.
So, for most people thinking of buying their first sub, unless they have a clued-in friend volunteering to study their room, this is beyond their level.

Another thing you mention is "routinely getting to 100dB". Again, this requires knowledge. The Fletcher/Munson curve, and perhaps measuring the music / movies you like to listen to, at your comfort levels, taking into account your room, closeness of neighbors, living situation etc.
So, probably over the heads of people buying their first sub, or their first hi-fi system.

The overarching theme I'm getting, as I learn more, is that for subs and LF, unlike bookshelf speakers and audio electronics, you really need to measure or you're in the dark.
Perhaps the first sub you get serves as your gateway to learn more.

 

[jsilvela]

In a film soundtrack a subwoofer is fed by the LFE channel. It is short for Low Frequency Effects. No effects, no sub output.

That's only true if you connect your SW to an AVR with an LFE channel.
In my system right now, I'm connecting the sub with an RCA splitter out of the two-channel preamp.
I do see the sub activate in "non-effects" scenes, and things like car rumble or footsteps on wooden floors become much more real.
On top of which, modern soundtracks with synths that go low, also improve.

 

[sigbergaudio]

This is brilliant, thank you!
It is the kind of information that I wish was given, rather than disparaging remarks on size/number/brand.
You need to have a measurement mic and a program like REW, though.
So, for most people thinking of buying their first sub, unless they have a clued-in friend volunteering to study their room, this is beyond their level.

Another thing you mention is "routinely getting to 100dB". Again, this requires knowledge. The Fletcher/Munson curve, and perhaps measuring the music / movies you like to listen to, at your comfort levels, taking into account your room, closeness of neighbors, living situation etc.
So, probably over the heads of people buying their first sub, or their first hi-fi system.

The overarching theme I'm getting, as I learn more, is that for subs and LF, unlike bookshelf speakers and audio electronics, you really need to measure or you're in the dark.
Perhaps the first sub you get serves as your gateway to learn more.

I think this is like any other hobby, it's hard to make the right choices without taking time to learn about the subject. With regards to your final comment and I partly agree, it's perhaps more obvious with a subwoofer. But there are lots to learn about loudspeakers as well, and I think a lot of people could have saved themselves a lot of expensive purchases and lots of replacements by spending time trying to understand why they weren't happy with their current speakers instead of just randomly trying something else.

 

[jsilvela]

I think this is like any other hobby, it's hard to make the right choices without taking time to learn about the subject. With regards to your final comment and I partly agree, it's perhaps more obvious with a subwoofer. But there are lots to learn about loudspeakers as well, and I think a lot of people could have saved themselves a lot of expensive purchases and lots of replacements by spending time trying to understand why they weren't happy with their current speakers instead of just randomly trying something else.

100% agree.

 

[bodhi]

With subwoofers the first thing before buying one would be to listen a system with good measuring low end. The thing is that flat response to 20 or 15, while being kind of gold standard, does not sound intimidating or flashy. Most often be it movies, series or music, it's just a pinch of spice on top. Until once in a while it isn't.

My brother has SVS SB-2000 sitting in a corner of usual small European living room with concrete walls with no eq and gain set to about 70%. Holy hell that thing punishes! He can't of course keep it on most of the time for obvious reasons. I'm sure most people listening to that system would come to a conclusion that subs can be kind of fun once in a while but generally not worth it.

 

[Sancus]

You need to have a measurement mic and a program like REW, though.

FWIW, REW is free and I think an $80 UMIK is one of the best values in audio. It's not something you'll ever need to upgrade and you can use it both for room measurements and as a good SPL meter. I actually think anyone spending more than, like, $500 on audio gear should definitely buy one and learn the basics of REW. It's an investment of a few hours, but it's one of those things that will always be useful to know and will likely save you time and money in the future.

 

[jsilvela]

FWIW, REW is free and I think an $80 UMIK is one of the best values in audio. It's not something you'll ever need to upgrade and you can use it both for room measurements and as a good SPL meter. I actually think anyone spending more than, like, $500 on audio gear should definitely buy one and learn the basics of REW. It's an investment of a few hours, but it's one of those things that will always be useful to know and will likely save you time and money in the future.

Could not agree more, but I think a large percentage of people "getting into audio" would be completely unwilling to do this.
"Just tell me what to buy". Personally, getting the UMIK-1 and starting to use REW has been a complete eye-opener.

 

[bodhi]

FWIW, REW is free and I think an $80 UMIK is one of the best values in audio.

Unfortunately the first measurements cause the veil of subjective enjoyment to fall. Fast forward a year and you are down thousands and are still anxious about some dips in midbass when last year the only thing you worried about dips was you must have both ranch and taco varieties for the new year party.

 

[sigbergaudio]

With subwoofers the first thing before buying one would be to listen a system with good measuring low end. The thing is that flat response to 20 or 15, while being kind of gold standard, does not sound intimidating or flashy. Most often be it movies, series or music, it's just a pinch of spice on top. Until once in a while it isn't.

My brother has SVS SB-2000 sitting in a corner of usual small European living room with concrete walls with no eq and gain set to about 70%. Holy hell that thing punishes! He can't of course keep it on most of the time for obvious reasons. I'm sure most people listening to that system would come to a conclusion that subs can be kind of fun once in a while but generally not worth it.

Yes, this is an interesting point. A well EQed system sound so much more tidy that it's not necessarily that impressive at the first listen, but oh so much better in the long run.

And not sure what you mean by flat response to 20hz, but just wanted to clear up (for others if that's not what you mean) that one doesn't typically want a flat response, but a smooth response. You're generally looking for a flat response from 20-100hz and then a steadily falling slope to around 1khz where the in-room response of the speakers go somewhat flat again, until 8-10khz where it again falls off. Typically something along these lines:

 

[jsilvela]

Unfortunately the first measurements cause the veil of subjective enjoyment to fall. Fast forward a year and you are down thousands and are still anxious about some dips in midbass when last year the only thing you worried about dips was you must have both ranch and taco varieties for the new year party.

Given your user name, you could write on the path to enlightenment!
First learn that your subjective enjoyment is as nothing, and measure.
Then learn that objective perfection is not attainable. etc.

Had a good laugh with your comment.

 

[Sancus]

You're generally looking for a flat response from 20-100hz and then a steadily falling slope to around 1khz where the in-room response of the speakers go somewhat flat again, until 8-10khz where it again falls off.

Damn, basshead detected -7ish dB from 100 to 1k is quite a slope. I'm only -5 nornally. I think natural slope for "a good speaker" in-room is usually -3-4ish. Most people prefer a little more than that though.

I usually see "flat to X" being used to mean no rolloff due to lack of output though. Of course if you want more of a slope then you need even more sub power

 

[sigbergaudio]

Damn, basshead detected -7ish dB from 100 to 1k is quite a slope. I'm only -5 nornally. I think natural slope for "a good speaker" in-room is usually -3-4ish. Most people prefer a little more than that though.

I usually see "flat to X" being used to mean no rolloff due to lack of output though. Of course if you want more of a slope then you need even more sub power

If the response of the speakers and sub is relatively even (so no peaks boosting certain frequencies) you can get away with more boost. Personally I prefer 6-7dB. Should we believe the limited Harman study people are anywhere between 5-10dB. Yes, I think 3-4dB would sound thin to most people. I'm here assuming a setup where 1-10khz is pretty flat, so 100-1khz is practically almost the same as 100-10khz.

Also note the gradual slope all the way, this too makes more boost acceptable, because the difference between low bass and mid bass isn't really that big. A lot of people have a speaker that are lacking in midbass so the speakers are actually quite flat in-room up to 100hz (either due to the speaker design or due to SBIR effects that suck out parts of the 100-300hz area), and they have a hard tilt up to 100hz because the subwoofer is tuned several dB higher than the speaker. I have measurements for all kinds of rooms I just shared one I happened to have loaded in REW. I'm actually in the process of re-tuning my main listening room due to having new speakers in there, so perhaps I can share the result there pretty soon.

The curve I posted isn't a perfect one, it should have a bit more level in the 100-500hz area (or possibly reducing the sub with 1dB or so), and it's got a bit of peaks making it seem to drop off at 40hz. The point was the gradual slope. As you can see below it's just slightly above 1dB/octave drop, and mostly within +/-3dB (admittedly with some smoothing) with that slope, so not horrible for an in-room measurement.

 

[thewas]

Damn, basshead detected -7ish dB from 100 to 1k is quite a slope. I'm only -5 nornally. I think natural slope for "a good speaker" in-room is usually -3-4ish. Most people prefer a little more than that though.

Most people prefer flat direct sound, the slope at the listeners position depends on the directivity of the loudspeakers, room reverberation slope and listening distance, which is why above transition frequency correcting the LP response to some predefined targets usually doesn't work well. More about it here https://www.audiosciencereview.com/...ut-room-curve-targets-room-eq-and-more.10950/

 

[bluefuzz]

-7ish dB from 100 to 1k is quite a slope.

I aim for a straight line 15 dB drop between 20 Hz - 20 kHz, or about 1.2 dB/octave. That's 5ish dB between 100 and 1 kHz.

 

[sarumbear]

That's only true if you connect your SW to an AVR with an LFE channel.

I said "in a film soundtrack a subwoofer is fed by the LFE channel." How can you control a film soundtrack without an AVR or a multi-channel device set-up that works like it?

I do see the sub activate in "non-effects" scenes, and things like car rumble or footsteps on wooden floors become much more real.

Car rumble or footsteps are what is called effects. The word effect is not to be confused with visual effect. We are talking audio here.

What I am trying to explain is bass-management where low frequencies are fed to a subwoofer and LFE where there is a separate track that feeds the subwoofer directly are not to be confused.

 

[jsilvela]

I said "in a film soundtrack a subwoofer is fed by the LFE channel." How can you control a film soundtrack without an AVR or a multi-channel device set-up that works like it?


Car rumble or footsteps are what is called effects. The word effect is not to be confused with visual effect. We are talking audio here.

What I am trying to explain is bass-management where low frequencies are fed to a subwoofer and LFE where there is a separate track that feeds the subwoofer directly are not to be confused.

I think you're being a tad academic here about LFE.
In my (insert-deprecation-here) REL sub, you have high level inputs for general audio and a separate ".1" for those who are using an AVR with this kind of capability.
I do not use the ".1" input, nor do I use an AVR any more.
When movies are played in my stereo system, I still get the car rumble and steps on wooden floors.
And since you make such distinction between movies and music: Pink Floyd "The Wall" has plenty of rumble, door noise etc. and certainly does not use a LFE track.