Mid-bass lacking

Talley

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I have low energy in my room/speakers from the 80-160hz range. I've played around with REW room sim and it appears to me that it's just a natural limit of my room dimension no matter what location. I can "smooth" it out some... but it will always be of little energy compared to the rest of the system

I need to work on speaker placement. My sub crossover is set to 80hz. My speaker woofers have solid response down to 28hz in my room and still are adequate to 22hz if I run them ported. They have really good response below 80hz. Surely it cannot be my speakers alone. I feel confident that it is room interaction playing the battle here.

Any other thoughts on this? I know the crossover from the woofer to the midrange on the ultra towers is at 160hz ironically and I appear to have decent energy above this portion.

woofer.JPG
 
My speakers also have very good response (conservatively) rated to 27Hz. I have run them with the receiver crossover for the mains set to 40Hz for years. To me it just sounds much better than 80Hz. I'd suggest you try yours at 60Hz, 40Hz and full range and see which you like best. I am NOT a firm believer in the 80Hz rule that so many people are enamored of. Do what sounds best to you in your room, not what everyone else says you should do.
 
Well I may have to play around with the manual controls but I like DIRAC to handle it's thing but with the xmc-1 version of dirac you cannot control the crossover point.

You can get a better idea of the overal "energy" of the midbass range here:

midbass.JPG
 
Hmmm, can you change the crossover point after you have run DIRAC?
 
When you run dirac you can change crossover points post calibration?

I wasn’t aware of this.
 
Dirac has complete control over the crossovers, timing/delay, etc. The only thing you can adjust is the desired response and the window of what frequencies to adjust.

I spent some time this past sunday playing with the location of the speakers and was able to bring back the 120-200hz range and the sound is much better and soundstage too. Previously was at 28" from tweeter to front wall distance and I moved it out to 38" and man huge difference.

But no matter what I have an issue with the 100hz range. Not alot I can do since that falls into my room dimension unless I load the room with absorption which could have more negative affects.

here is the L/R main in reference mode, no processing at the new location.

...I'm not done... still going to play around with location more. I'm worried about the tweeter response. Maybe it was my mic positioning or something. Need to check on that too.

new location.jpg
 
You run dual subs up front next to your mains, correct?
 
You run dual subs up front next to your mains, correct?
This was just the mains. I was going for best placement for them first. This was individual left and right main and also sealed.

Porter is a huge boost on the bottom end. Response down into 24 range.

The subs give me a response down into 14hz
 
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I guess what I meant to say... is if if your subs are in the vicinity of your mains, bump that X-over up to 100Hz and see what happens.
 
LOL *forehead smack*
 
Can you push the area down above 160 Hz with Dirac? Maybe the level is just off in the crossovers on the woofers compared to the mids/tweets. Have you verified you have the speakers connected in the correct polarity? You could also check the woofers separately with a 9V battery test. It's possible (although probably not likely) one of them got mis-wired from the factory causing a cancellations.
 
I don't know why anyone would want to run a full range floor standing speaker (L&R) as anything less than in full range... Cross your sub over down towards the bottom of the L&R speakers... I have found that about a 15hz overlap works well... If your floor standers go down to 30hz then cross your sub at 45hz ish for example, and let those floor standers sing...
 
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I don't know why anyone would want to run a full range floor standing speaker (L&R) as anything less than in full range... Cross your sub over down towards the bottom of the L&R speakers... I have found that about a 15hz overlap works well... If your floor standers go down to 30hz then cross your sub at 45hz ish for example, and let those floor standers sing...
I know what your saying and agree to a certain point, I do think that you need to give the full range speakers a bit more breathing room than just at the lowest they can handle. 60-80Hz is really my standard if possible as a crossover is not a brick wall and does go past that setting by about 20Hz in a slope. A sub will deal with the lower frequencies far better than any speaker unless it has a dedicated driver just for those lower octaves.
 
I know what your saying and agree to a certain point, I do think that you need to give the full range speakers a bit more breathing room than just at the lowest they can handle. 60-80Hz is really my standard if possible as a crossover is not a brick wall and does go past that setting by about 20Hz in a slope. A sub will deal with the lower frequencies far better than any speaker unless it has a dedicated driver just for those lower octaves.

I agree. A speaker might have output down to 30 Hz but that doesn't mean it can get that loud at those frequencies. Having the crossover higher (I personally use 60 Hz) keeps excursion off your mains and leads to a cleaner overall sound coming out of them.
 
Maybe a stupid question but did you try to reverse the polarity of the subs vs mains? You don't dual wire by any chance? I've seen reverse polarity in factory built high-end cables (markings were backwards on the other end).
 
Valid point. Sometimes a polarity flip does the trick
 
Warmth suckout, euch! is very common. Sitting at half height and half width is kinda asking for modal trouble for a start! But fibre treatment panels can have absorption peaks due to damped membrane/panel effect. Fwiw in Pro Surround Mixing the 5 speakers are recommended and preferred full range.
 
It is probably a room effect but...
You can measure SWs and Mains separately to see if the SWs rolloff is too shallow and thus impacting the mid bass. If so, then try to run Dirac again after the suggested polarity change or after setting the HSU 'crossover' to 80 or 90 Hz. The HSU manual indicates this is actually just an optional 24 dB low pass filter setting.
 
My experience has been that if the lower midrange is lacking and you have known capable speakers, you have to experiment with SW+main polarity and sub crossover frequency and phase settings. When the phase is aligned with the mains, you experience usually a very noticeable and tactile boost to bass. In some rooms subs sound best when cut at 40-50hz and in some rooms you want the added kick at 80hz.

Measurements help a lot and if there is a clear drop around the crossover frequency it means your phase/delay settings are off or your mains drop before the subs come to play. The former is way more common in my experience. Of course like Mr. Geddes says, having only one sub in the room will always be suboptimal and your listening experience can change radically by moving your chair a few inches.

The very first thing that came to my mind when I saw the first frequency sweep was that the midrange and the subs were aligned but the midbass was off polarity, causing it to suck out on both upper and lower crossover frequency.
 
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I have low energy in my room/speakers from the 80-160hz range. I've played around with REW room sim and it appears to me that it's just a natural limit of my room dimension no matter what location. I can "smooth" it out some... but it will always be of little energy compared to the rest of the system

I need to work on speaker placement. My sub crossover is set to 80hz. My speaker woofers have solid response down to 28hz in my room and still are adequate to 22hz if I run them ported. They have really good response below 80hz. Surely it cannot be my speakers alone. I feel confident that it is room interaction playing the battle here.

Any other thoughts on this? I know the crossover from the woofer to the midrange on the ultra towers is at 160hz ironically and I appear to have decent energy above this portion.

View attachment 5993
Judging by what I see, there is probably more than one problem. First, there is a very good chance that your midrange driver is more efficient than your woofer. This does happen sometimes, and I must admit that I don't know why speaker designers let that go by. The smaller peaks and dips may be either in the frequency response of the driver, or interaction with the room, or a combination of the two. The subwoofer being stronger is just a matter of lowering its level a bit to match the woofer. If the speaker has a midrange level control, try turning that down a bit. If it doesn't, an attenuator network could be added between the crossover and the midrange. I did something like that in the front mains of my home theater setup to tame overbright tweeters.
 
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