2. misc-audio
  3. 161428-74231

Room Treatment Question, lost the lowest bass notes.

This is what I have:
25 x 40 ft room 12 to 15 ft tall ceilings

The stereo is on the narrow wall on one end of the room. (I can move it 90 degrees if needed).
I have a pretty good system, Wilsons, Audio Research, VPI, I do not think I have to give what components are. They are considered high end.
Here is my problem.  My seating position is about 15 ft away from the speakers.  The lowest notes that I know that are on the recording are NOT being presented. For example: Lyle Lovett - She has already made up her mind.  There are a few super low notes on the song. I have heard them before when I had a lesser stereo.

I did find that when I stood near the open door at the far end of the room, I can hear them. But when I move towards the center of the room near the far wall, They go away. It is very easy to hear the drop off.

I spoke to a couple of HiFI shops in the LA area. One mentioned a Node Cancellation. I do not know what that is.
I added (2) 2 x 4 section of sound absorption material high on the back wall. The only conclusion I came up with is the low notes are being cancelled once they bounce off the back wall and head back to the front wall. Stop the bounce and the low note have a place to go.

I am thinking correctly here or am I just reaching for straws, and I am. 

I am no scientist. Please answer in non scientific terms.

Thank you. 
Bill 


128x128bill_peloquin

Showing 4 responses by millercarbon

millercarbon's avatar
millercarbon
12,531 posts
 
That's why I'm looking forward to checking out Mike Lavigne's place this weekend. Some audiophiles are coming up from Portland. First stop my place, then on to Mike's. Kind of like a pub crawl. Heh.  

My room for sure has problems. Had a friend over a very long time ago, Holly Cole hits this one note and its just crazy overload loud. Told my friend sorry its the room I'm working on it. He says no way she just overloaded the mic. But I knew better. The corner tunes you can see in my system pics virtually eliminated this resonance. Cleaned up some other stuff as well.  

That like I said was a very long time ago. Like at least 20 years. My system is a whole lot better now. Room problems that back then blended in with other problems now stand out as room problems. To me anyway. Everyone so far thinks the room sounds great. Better than average sure. But not great. Mike Lavigne though, now THAT'S a ROOM!  

Bet your bottom dollar my eyes will be peeled every bit as much as my ears will be taking it all in especially looking for ideas to improve the sound in my room.
millercarbon's avatar
millercarbon
12,531 posts
 
Your #6, when my room was brand new and empty, literally just one chair and the stereo on the floor, no room treatment at all, the bare walls created obvious modes at every frequency. There was a test CD with tones and some frequencies you could hear the dips and peaks dramatically come and go as you move around, sometimes in a foot or less. We don't notice this because most rooms are nowhere near so empty, and everything in a room either absorbs or reflects and scatters. So usually we only notice the modes with bass. But they're everywhere.
millercarbon's avatar
millercarbon
12,531 posts
 
Honestly, it hardly matters which sub you use. I have three different types in my room. https://systems.audiogon.com/systems/8367 They all work together perfectly, and blend seamlessly with the mains.

The problem with EQ is you can only get it flat by putting more bass into the room. Bass energy takes time to dissipate in the room. Putting more bass into the room with EQ always results in slower muddier bass. So then you have to remove the extra bass with bass traps. When instead you could use multiple subs. Because there are more each one can put out less bass. It all adds up to the correct amount of bass. Its smooth because they're in different locations, greatly reducing the amplitude of the modes. Its just a way more elegant and effective solution all the way around.
millercarbon's avatar
millercarbon
12,531 posts
 
Perfectly normal. Happens everywhere. Very low bass waves are much longer than even a large room. So they reflect back and the same wave cancels itself at certain locations. That's why you stand somewhere and hear it, move somewhere else you don't. Also you will notice some frequencies are way too loud depending on where you stand. Where this happens depends on the frequency. With just two speakers all you can do is move them around, and all that will do is move the lumpy bass around. 

None of the stuff the shop is suggesting will do anything other than move the same lumpy bass around. The only real solution to smooth even powerful and DEEP bass is multiple subs. Preferably four. Search DBA, distributed bass array, or Swarm subwoofer system.
More to discover