The room of no bass

play with placement
your speakers or your listening position is likely in a room mode which has serious dip in the bass region (very common). you need to find a way to localize your biggest room modes and to NOT place your speaker or you listening spot in one of your worst room modes.
if you can, use a mic and arta and measure your room.
if you dont have the necessary equipment, I find the 38% rule a good beginning to find good placement

THE 38 PERCENT RULE

The placement method used here is based on the "38 percent rule" which theorizes that the best listening position is 38 percent into the length of the room, when measured from either the front or rear wall. This offers the best compromise of peaks versus nulls for any given room size. For 2-channel listening you'll get the flattest low frequency response by sitting 38 percent of the way back from the front wall. However, this is not practical in many home theaters, especially those with large screens, because that puts you too close to the screen. Fortunately, you can get the same benefit by sitting 38 percent of the room length when measured from the rear wall.

Please understand that 38% is one theoretical best location to begin measurements, but it may not end up the best place to sit due to other factors - wall properties, speaker location, speaker type, furnishings in the room, and a host of other conditions that can affect frequency response. The only way to know which location really is flattest is to measure the low frequency response at high resolution using software such as Room EQ Wizard or FuzzMeasure as explained in our Room Measuring Primer article.

Once you know the ideal listening position from the front or rear wall, the next step is to place the loudspeakers. The speakers and listening position should be at the points of an equilateral triangle, as shown in Figures 1 and 2. Note that the theoretical point of the triangle is just behind your head, with the axis lines grazing your ears.

If you have suitable software such as the programs linked above, or the RealTraps Test Tone CD, or another way to accurately measure your room's low frequency response, you can experiment with different speaker distances by sliding both speakers along each axis while you measure the response. Otherwise, put them along the axis at a distance that is convenient and makes sense for the size and layout of your room. Too often people obsess over minute details that matter only a little, while ignoring ergonomic concerns that matter much more.


http://realtraps.com/art_room-setup.htm
https://www.gearslutz.com/board/so-much-gear-so-little-time/163019-38-rule.html
That is very interesting. I will experiment when I have time.
One other thing I noticed. I have to run my subwoofer in reverse polarity in order to not canceling out bass against the front speakers. That seem very strange. And it's not the subwoofer because I have two subwoofers and they all behave the same way. Maybe the room is also messing with the bass phase too?
 
That is very interesting. I will experiment when I have time.
One other thing I noticed. I have to run my subwoofer in reverse polarity in order to not canceling out bass against the front speakers. That seem very strange. And it's not the subwoofer because I have two subwoofers and they all behave the same way. Maybe the room is also messing with the bass phase too?
changing polarity of subwoofer is needed in every setup. reason is simple: sometime you can be lucky and the phase of the subwoofer is the same as your speaker.
to be sure your sub is in phase, you should select the polarity that gives you the most bass when your minas and sub are playing at the same time.

The room is messing with your bass. the problem is not your speakers or your sub.

look for room modes and speaker placement.

For example, I used to have 15 +- from flat in the bass under 250hz. with proper placement, understand my room modes and avoiding them, finding with measurments the place I could actually place my speaker and listening position without triggering the major room modes brought my +-15db to +-7-8db. bass peak and dips are very real and will ruin any speakers (in every room will show from 10 to 25 db deviation from flat in the bass departments).

can you tell me more about your room dimension and your listening position placemnt and speaker placement. how far away from walls, ect.
I have my speakers 3 feet away from front wall and two feet from side walls...
 
changing polarity of subwoofer is needed in every setup. reason is simple: sometime you can be lucky and the phase of the subwoofer is the same as your speaker.
to be sure your sub is in phase, you should select the polarity that gives you the most bass when your minas and sub are playing at the same time.

The room is messing with your bass. the problem is not your speakers or your sub.

look for room modes and speaker placement.

For example, I used to have 15 +- from flat in the bass under 250hz. with proper placement, understand my room modes and avoiding them, finding with measurments the place I could actually place my speaker and listening position without triggering the major room modes brought my +-15db to +-7-8db. bass peak and dips are very real and will ruin any speakers (in every room will show from 10 to 25 db deviation from flat in the bass departments).

can you tell me more about your room dimension and your listening position placemnt and speaker placement. how far away from walls, ect.
I have my speakers 3 feet away from front wall and two feet from side walls...
The room is 8H x 24W x 12D.
The speakers are placed at the center of the longer walls. The fronts are about 6ft apart right up against the wall toed in towards the listener's head. The subwoofer is on the left of the mains in the corner.
 
The room is 8H x 24W x 12D.
The speakers are placed at the center of the longer walls. The fronts are about 6ft apart right up against the wall toed in towards the listener's head. The subwoofer is on the left of the mains in the corner.

a speaker right against the wall will create real problems in the bass.
My huge 200L cabinets with 12" woofers have the same problem. even with those huge speakers, placement is crucial. if too close to the wall, it is a boomy mess with dips and peaks that make it terrible sounding in the bass.

for good bass performance in room, which is arguably the most difficult thing to achieve in home hifi, placement is very important.
you should try to follow my advise about placemnet and room modes.

good luck!

for the beggining, id try to make the soun d the best WITHOUT subwoofer, then add the subwoofer integration once you are satisfied with the way your mains sound.
 
a speaker right against the wall will create real problems in the bass.
My huge 200L cabinets with 12" woofers have the same problem. even with those huge speakers, placement is crucial. if too close to the wall, it is a boomy mess with dips and peaks that make it terrible sounding in the bass.

for good bass performance in room, which is arguably the most difficult thing to achieve in home hifi, placement is very important.
you should try to follow my advise about placemnet and room modes.

good luck!

for the beggining, id try to make the soun d the best WITHOUT subwoofer, then add the subwoofer integration once you are satisfied with the way your mains sound.
Yea I am gonna do some serious rearranging soon.
 
Ever read through any of the old HiFi magazines and articles from the 1950s?

Audio enthusiasts were making all kinds of aggressive efforts to get good sound. Some of them broke out the power tools and cut holes in their walls to mount large drivers directly flush into the wall (usually a wall where something like a closet or the garage was on the other side).
 
If it's that bad, are your speakers wired in phase? Sorry, had to ask.

Yes, they are.

That is very interesting. I will experiment when I have time.
One other thing I noticed. I have to run my subwoofer in reverse polarity in order to not canceling out bass against the front speakers. That seem very strange. And it's not the subwoofer because I have two subwoofers and they all behave the same way. Maybe the room is also messing with the bass phase too?

Take the subwoofers offline. Double and triple check that in the AV receiver setting you use, there is no "surround" feature which sometimes reverses the polarity on one speaker to give a more diffuse soundfield. Then double check with a mono source that you get a really stable and solid center image, and should have decent bass response from your front speakers. If your wiring is polarity consistent, and you still get no bass from just the fronts, then reverse the wiring to one speaker only and then double check.

Once you determine you get real bass and stable center image with mono, then place the sub temporarily in the middle between the two fronts. Run it in phase and out of phase with your fronts and retest for center image and bass reinforcement. If you have to run it out of phase, then your sub signal or sub amp is inverting the signal relative to your front speakers, and you'll have to take that into account when wiring your system.

Not all manufacturers keep absolute phase throughout their system. Double check if there is a phase or polarity switch or adjustment to your sub or AV gear. Keeping absolute polarity is sometime difficult in multichannel systems, as well as complicated or processor driven systems.

Once you have figured out you have absolute polarity, then try it with your regular music sources, to determine if they are in stereo phase or stereo out of phase. This will help to decide if its your source material, gear, or something else downstream.

Then and only then can you start moving things around the room to see if the bass response gets better (peaks) or worse (nulls) as you search for a setup which is audibly and visibly acceptable.
 
Then and only then can you start moving things around the room to see if the bass response gets better (peaks) or worse (nulls) as you search for a setup which is audibly and visibly acceptable.

agree. make sure you have absolute phase between mains and subs
 
changing polarity of subwoofer is needed in every setup. reason is simple: sometime you can be lucky and the phase of the subwoofer is the same as your speaker.
to be sure your sub is in phase, you should select the polarity that gives you the most bass when your minas and sub are playing at the same time.

I just caught this thread, and was going to suggest looking at the polarity of the subwoofer. If it's out of phase with the rest of the speakers, that would certainly account for some bass cancellation.

Beyond that, move the speakers closer to each other, then further away from each other.

Sounds like there is some sound wave cancellation going on here in the lower frequencies.

bs
 
Hey, bshorey, your community has had some rough stuff with traffic accidents recently, thoughts out to Gilroy. Was out there last August visiting Gilroy Gardens, the flower gardens adjacent, and the area.
 
Take the subwoofers offline. Double and triple check that in the AV receiver setting you use, there is no "surround" feature which sometimes reverses the polarity on one speaker to give a more diffuse soundfield. Then double check with a mono source that you get a really stable and solid center image, and should have decent bass response from your front speakers. If your wiring is polarity consistent, and you still get no bass from just the fronts, then reverse the wiring to one speaker only and then double check.

Once you determine you get real bass and stable center image with mono, then place the sub temporarily in the middle between the two fronts. Run it in phase and out of phase with your fronts and retest for center image and bass reinforcement. If you have to run it out of phase, then your sub signal or sub amp is inverting the signal relative to your front speakers, and you'll have to take that into account when wiring your system.

Not all manufacturers keep absolute phase throughout their system. Double check if there is a phase or polarity switch or adjustment to your sub or AV gear. Keeping absolute polarity is sometime difficult in multichannel systems, as well as complicated or processor driven systems.

Once you have figured out you have absolute polarity, then try it with your regular music sources, to determine if they are in stereo phase or stereo out of phase. This will help to decide if its your source material, gear, or something else downstream.

Then and only then can you start moving things around the room to see if the bass response gets better (peaks) or worse (nulls) as you search for a setup which is audibly and visibly acceptable.
I am using an Yamaha RX-A830 receiver, Klipsch Synergy F30 fronts and SW-450 subwoofer.
I use YPAO to calibrate all speakers and the receiver tells me all of them are wired correctly. I listen to 2 channel mono or stereo music with just the fronts on no problem with bass and I know what out of phase speakers sound like. However being dual 8 in woofer floor standing speakers they sound thinner as I move from the center of the room to my couch which is by the other wall the speakers are sitting. Due to space limitation, I can not place the speakers more than 6 inches from the back wall but the front speakers are front ported. The subwoofer sits in the corner.
I tried both subwoofers. The Onkyo one does not have phase switch and the Klipsch has the phase switch turned to 0 degrees. Both behave the same after calibration canceling out the fronts. I can either go into the receiver to change phase to reversed or change the switch if there is one. When phase is revered, I can hear big increase in bass.
I have tried turning the setup 90 degrees and it made it even worse. The region to get proper bass response is off to the side where my couch and TV is in the layout.
The other thing I tried is to mess with my subwoofer distance in the settings which intern mess with phase in respect to the front speakers.
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I would recommend doing things the other way around. Forget about the fronts rears and sides, and test things out with only your subwoofer putting out sound.

The ideal situation would be white/pink noise playing from the sub only and a calibrated measurement microphone at your listening position, with a spectrum analyser to tell you what exactly is going on at low frequencies, with only the subwoofer and the room affecting the acoustics. You can then try moving the subwoofer around and see how this affects your measurements.

If it is not possible to use a measurement microphone or generally a decent microphone with a good LF response, you can use your ears and sine waves, although this would be far less accurate. Just make slow sweeps from 10 Hz to around 100Hz and see if you notice any changes in the appearant loudness. Move it around, keep it further away from walls, try putting it directly in front of you and see how this affects the LF response of your room. When you have found a location which seems good, play some bass heavy music such as 70's rock through the sub alone and see what it sounds like. You are trying to get a natural LF response from the subwoofer alone trying to ignore the fact that there is no mids and highs. When you are happy with the LF, leave the sub where it is and do not change the settings.
Then, bring in the fronts only and mess with their placement until the sound makes sense, this time using more natural music, preferably classical. A full orchester should sound natural like a full orchester does.
When you have a natural image with just the fronts and sub, try bringing in the rest, pair by pair.
The room has a bit of a wiered geometry for multichannel sound, but if you can get the sub and fronts to sound decent, you can probably make the rest sound acceptable.

I really don't think, your problems lie in the wood panels and I would not do any structural modifications in the room, until you know exactly what is causing your problems. If you have measurement equipment, you should repeat measurements when you bring in the fronts to see what changes in the response of the room. If you can post a graph of the room response on here, maybe we can come up with some good ideas.
 
The weird thing is when the sub is working on it's own, it sounds great. It's when I have the fronts playing at full range and sub also outputting some of the bass, that's where the problem shows up. I can go into the amp and select the fronts to be small and the sub sounds normal right away.
That room has some weird geometry that's causing some weird standing waves exactly out of phase when speakers are placed at certain locations.
 
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