Subwoofer speed is in the room, not the box
First, if you like swarm, that’s fine, please start a thread somewhere else about how much you like swarm.
I want to talk about the impression that subs are fast or slow compared to planar or line sources.
The concern, and it’s correct, is that adding a subwoofer to say a Martin Logan or Magneplanar speaker will ruin the sound balance. That concern is absolutely a valid one and can happen with almost any speaker, not just speakers with tight dispersion control.
What usually happens is that the room, sub and main speakers aren’t integrating very well. Unfortunately for most audiophiles, it’s very hard to figure out exactly what is wrong without measurements or EQ capabilities in the subwoofer to help you.
So, there’s the myth of a small sub being "faster." It isn’t. It’s slower has worst distortion and lower output than a larger sub but what it does is it doesn’t go down deep enough to wake the dragons.
The biggest problems I’ve heard/seen have been excessively large peaks in the subwoofer range. Sometimes those peaks put out 20x more power into a room than the rest of the subwoofer. Think about that!! Your 1000 W sub is putting out 20,000 watts worth of power in some very narrow bands. Of course that will sound bad and muddied. The combination of sub and main speaker can also excessively accentuate the area where they meet, not to mention nulls.
A lot is made about nulls in the bass but honestly IMHO, those are the least of our worries. Of course too many of them can make the bass drop out, but in practicality is is the irregular bass response and the massive peaks that most prevent any good sub from functioning well in a room.
Bass traps are of course very useful tools to help tame peaks and nulls. They can enable EQ in ways you can’t do without it. If your main speakers are ported, plug them. Us the AM Acoustics room mode simulator to help you place your speakers and listening location.
Lastly, using a subwoofer to only fill in 20 Hz range is nonsense. Go big or go home. Use a sub at least at 60 Hz or higher. Use a single cap to create a high pass filter. Use EQ on the subwoofer at least. Get bass traps. Measure, for heaven’s sake measure and stop imagining you know a thing about your speaker or subwoofer’s response in the room because you don’t. Once that speaker arrives in the room it’s a completely different animal than it was in the showroom or in the spec sheet.
Lastly, if your room is excessively reflective, you don’t need a sub, you need more absorption. By lowering the mid-hi energy levels in a room the bass will appear like an old Spanish galleon at low tide.
@audioquest4life If subwoofers and main speakers are integrated correctly there is no reason to turn the subs up or down with any genre of music. A system that is tuned correctly does not care what genre you are playing. When I use the term , system I include the room in that category. Most audiophiles are ball parking it with their ears which are extremely poor calibration devices. There is no substitute for measurement. |
Good thread, I don’t have a lot to contribute that has not already been said. But I have been highpassing all my speakers with an active crossovers for about 10 years now. Every speakers has sounded better with a highpass of 60hz or higher. The improvement subs bring is staggering when done right. With a 24db slope on both ends 80hz is about a high as I can go before I “hear” my subs (probably need better subs to go higher). 70hz is the sweet spot with my current speaker location and 24db slope. It measures flat and sounds good, I do have pretty large capable speakers that handle 70hz and up just fine. I find it silly when people chase bigger and bigger speakers at sky high prices for better bass, but refuse to try an actively passed sub system.
|
Same sentiment here. Perhaps not “silly” so much as unnecessarily complicated. 😅 I think the main crux of this topic is the cultural inertia that floor-standing speakers enjoy, as the overall concept predates active subwoofers, especially active subs implemented and EQ’ed as > 1 unit. The exact topics as covered in this (highly informative) thread seem rare convo’s among folks employing line arrays, since many (hifi) examples do not reach very far below 100 Hz (mids/high drivers). Sub crossovers below 80 Hz accordingly and quickly become irrelevant for such cases. |
@mijostyn "If subwoofers and main speakers are integrated correctly there is no reason to turn the subs up or down with any genre of music. A system that is tuned correctly does not care what genre you are playing. When I use the term , system I include the room in that category. Most audiophiles are ball parking it with their ears which are extremely poor calibration devices. There is no substitute for measurement/ " I completely understand the audiophile aspect but that is not the point I was trying to convey. I use technical measurements, not all ears either. It is entirely irrelevant for me to put an audiophile hat on when I want gut wrenching bass that overwhelms the room and senses. I am literally talking loud parties, disco bass, chest thumping rock, not wine sipping bourbon tasking listening sessions where I am trying to listen to the wood thwack on the drum set or listen for the shimmer of the cymbals. That all goes out the window for me when I am in party mode. Yes, a properly EQed system will provide some of what I am looking for, but this does not fit my lifestyle 100%. I believe OP implies not all things are equal for everyone. I have spent in excess of 100K in building a new listening room in our new retirement house with acoustics in mind. Trust me, I get the bass rationalization. However, I don’t feel the need to split the main audio signals when I can take accurate measurements and feel just as content in my own world. I have had drummers come to the house and listen to my system and tell me this was the only system they ever heard that played drums the most realistic they have ever heard, outside of a live drum session. That is enough for me. I will conclude that yes, the OP has a valid point and something that audio enthusiasts should be aware of but there are many aspects to consider when getting your system optimized. Been doing this for 40 years. Remember, there is world of counterfactuals out there. |
Too many speaker buyers take the speaker specs far too literally and think that knowing the -3dB point of a speaker in an anechoic chamber will be close to what happens in their room. From their perspective, if you want more bass you need a speaker with a lower -3dB point.
|
