What's a realistic expectation for bass performance?

[mightycicadalord]

So I've got all the ingredients, two neutral mains, two subs, dsp for them all, a decent selection of porous absorbers up to 6 inches thick, two 4' tall triangle shaped corner traps. It's all in a 15-16'x20+ ft room (the back wall isn't really there, it goes into other rooms.

I am super happy with everything from the tops, but not anything below like 200hz.

I've messed with placement but seem to always have some nulls in the bass and can't find a compromise I'm happy with. Seems like I can either get punchy back with no lows or all lows and no punch. Scientific words I know.

Should I try to target nulls or just be happy with what I've got. Am I chasing something unrealistic for my space and gear?

 

[Pdxwayne]

Please provide more details for your speakers, subs, crossover point, your sitting position distance from speakers and subs, etc....

I agree that to get below 200hz right is not easy. I am still messing with my stereo setup crossover points, slopes, etc, trying to blend in my 3 subs with my main speakers in my large living room, to get good punch and sub level shakes.

 

[TurtlePaul]

MiniDSP and a UMIK (and maybe fiddling with placement) is the answer.

 

[theyellowspecial]

Need room control DSP, like Turtle suggests.

 

[TurtlePaul]

We need to know more about your room, speaker placement and listening position. You say you have DSP. Do you have in-room measurements?

 

[ryanosaur]

Likewise, how did you determine what type of room treatments to utilize and their placement?
Putting finger on the scale for earlier questions about what speakers and subs you have, too, please.

 

[DonH56]

Start by reading this if you have not already: https://www.harman.com/documents/multsubs_0.pdf

How are you determining nulls, do you have REW or some other means of measuring the response as suggested above? Hard to offer advice with no data...

 

[mightycicadalord]

My speakers are DIY Amiga towers, subs are two Dayton Sub1000. I have the towers stacked on the subs about 2' into the room from the back wall and 3' in from the sides. Not best sub location but it sounded best to me still. Anything can be moved anywhere, I have stands for the towers. I'm in a 7ft equilateral triangle with speakers and LP.

Here is towers run full range. My DSP is voicemeter so I can pretty much do anything I want as far as EQ and Delay goes. I have the subs and towers crossed at 80hz but due to the nature of the DSP solution I'm having trouble figuring out how to measure through my xover and EQ. I'm sure I'll figure it out but in the meantime I can only do the towers and subs separately.

Here are the subs, I am utilizing an 80hz xover with DSP but I have the subs running with their xover dial at it's highest point just to avoid using them at all.

 

[DonH56]

I would start by figuring out why the right speaker has such a large dip at 100 Hz compared to the left speaker. Then I would move the subs to see if I could find a more optimal place to smooth the bass response (Todd Welti's paper may help with that). You can work with just the subs and find where to place them to reduce the nulls, then work on getting their delay and phase integrated with each other and the mains. The (a, one) big catch is that you may get much better results optimizing them as a group rather than individually; getting the individual responses (particularly delay and phase) may be challenging. One possible solution is to run MSO (https://www.andyc.diy-audio-engineering.org/mso/html/) and use it to determine the filter coefficients for your system. Place the subs according to one of Welti's configurations, run MSO, then adjust your DSP to match what it finds are optimal settings.

HTH - Don

 

[DWPress]

Well, you have a null at about 60-150Hz on both measurements and a XO at 80 which is in the middle of that. XO often follows the natural roll off of the mains, in your case around 40Hz but I'm not sure how helpful the Daytons would be below that. Any way you can get a measurement of both mains and drivers together to see how they sum in the room?

edit: And what @DonH56 said.

 

[TurtlePaul]

Speakers stacked on subs is wrong. Subs go against the wall and pull the speakers in front of the subs so they are 3 ft into the room. This alone will fix most of the issue.

 

[mightycicadalord]

Speakers stacked on subs is wrong. Subs go against the wall and pull the speakers in front of the subs so they are 3 ft into the room. This alone will fix most of the issue.

Here is same spot from side walls, pushed back against wall.

R

L

 

[mightycicadalord]

Here are the towers pulled away from the wall to 3ft. Seems the 100hz region is better.

 

[Abelard]

So I've got all the ingredients, two neutral mains, two subs, dsp for them all, a decent selection of porous absorbers up to 6 inches thick, two 4' tall triangle shaped corner traps. It's all in a 15-16'x20+ ft room (the back wall isn't really there, it goes into other rooms.

I am super happy with everything from the tops, but not anything below like 200hz.

I've messed with placement but seem to always have some nulls in the bass and can't find a compromise I'm happy with. Seems like I can either get punchy back with no lows or all lows and no punch. Scientific words I know.

Should I try to target nulls or just be happy with what I've got. Am I chasing something unrealistic for my space and gear?

You can’t ignore your electronics completely. Speaking from my experience only, replace the sub amplifiers if they are anything less than Hypex or Purifi. Class AB or Class G will only ever give you mush. I think Icepower has a new line but I would recommend even the older line over Class AB/G

 

[Pdxwayne]

My speakers are DIY Amiga towers, subs are two Dayton Sub1000. I have the towers stacked on the subs about 2' into the room from the back wall and 3' in from the sides. Not best sub location but it sounded best to me still. Anything can be moved anywhere, I have stands for the towers. I'm in a 7ft equilateral triangle with speakers and LP.

Here is towers run full range. My DSP is voicemeter so I can pretty much do anything I want as far as EQ and Delay goes. I have the subs and towers crossed at 80hz but due to the nature of the DSP solution I'm having trouble figuring out how to measure through my xover and EQ. I'm sure I'll figure it out but in the meantime I can only do the towers and subs separately.
View attachment 195671


Here are the subs, I am utilizing an 80hz xover with DSP but I have the subs running with their xover dial at it's highest point just to avoid using them at all.
View attachment 195672

Hmm....Even if you could get the mains and sub to blend well and have good frequency response from 200hz down, there is also issue of how much "punch" you can get using your current setup and room.

I can get excellent punch using just a 10" sub in my car. I can get excellent punch using a 10" sub in my small computer room. But, even with two 10" subs, they could only provide moderate punch in my large and open living room. When I had subs with three 15" woofers and crossed pretty high, only then I could get close to the kind of punch I like.

Since you have large and open room, I guess you need to accept your setup limitations and aim for more flat freq response by playing with subs and speakers positioning.

 

[TurtlePaul]

It is tiring seeing the influx of people who have no idea what they are talking about...

"Class AB and G amps"

"10 inch vs. 15 inch" ect.

This is ASR and people who don't know the audio science are taking over the discussions.

This was a SBIR problem, that is solved the way SBIR usually is solved - managing the distance from walls.

 

[Pdxwayne]

It is tiring seeing the influx of people who have no idea what they are talking about...



"10 inch vs. 15 inch" ect.

......

I fully understand SBIR issue. I have setups in small, medium, and large rooms and dealt with different nulls and peaks.

Why do you automatically assume people don't know what they are talking about when saying big quality subs crossed higher can give more punch than small subs in a large open concept room?

 

[whazzup]

*Based on what I have learnt from the fabulous material on ASR, but feel free to correct any of my 'layman' points below.

Firstly, the in-room response graph is generally downward sloping because higher frequencies tend to 'lose' energy quicker. In addition, the loudness contours show that lower frequencies have to be at higher levels before we 'hear' them adequately.

So in my mind, it makes sense that the same trend should apply to frequencies below 100Hz, meaning the lower the frequency, the higher the SPL. Unfortunately most of the cheaper subs are not made this way. They tend to have a sharp fall below 30-40Hz.

So in my case (of a small study room), I first increase the sub volume to be way higher than the main speakers. I have the knob at 3/4 to max. I tried to make sure that its 20-30Hz is at a SPL that will form the peak of the eventual downward slope. Obviously that meant that the frequencies from 20-100Hz are way too loud and boomy.

So I used a -15dB high shelf at 20Hz as a broad knockdown, then attacked the smaller regions. My final result, at my seated position (JBL A130 on desk, Klipsch sub under desk).

Measured distortion does rise at 20-30Hz, but I find it within acceptable margins and inaudible. And no chuffing from the port.

My messy EQ values for my sub.

I had also experimented with a flatter in-room response (<100Hz), but didn't really like it.

@mightycicadalord I would start by testing whether your subs are loud enough for you at say 30Hz, when they're at close to maximum output.

 

[ryanosaur]

Unfortunately most of the cheaper subs are not made this way. They tend to have a sharp fall below 30-40Hz.

I would agree that the weak link in our friendly OPs desired goal is the Sub1000s. While they are decent budget Subs, they lack the ability he seems to be looking for in Extension and SPL/mid-bass "slam."

This, of course, is aside from the Acoustics in his room. If OP were to upgrade something near term, this would be the target I recommend. Getting a pair of Subs that will contribute to his goal rather than hold him back is step one.
Step two is proper placement and integration.

Regardless of fixing nulls, this is also part of OP's question.

 

[okaudio]

I would agree that the weak link in our friendly OPs desired goal is the Sub1000s.

Maybe or maybe not based on the OP's "Seems like I can either get punchy back with no lows or all lows and no punch."

So if he can get enough "punch" already at some positions it might be possible to level it out without losing too much "punch". It's definitely worth a try with position/EQ first before throwing $$$ of subs at the problem.