EQ room correction, needfor chest thumping bass

[Psycher1]

Hello all,

I just got set up with a MiniDSP Flex (No DIRAC). I wanted to play with the EQ for my 2.1 system. I played around with REW, averaging from different seated positions, and seeing how EQ changes did or did not affect how the speakers responded in the room. After playing around some, and doing a few rounds of verification measurements, the graphs were putting a smile on my face.

The only aggressive gain was between 100-250hz, which needed a massive bump (summed between 12 and 16db, both speakers). As mentioned, after the bump, it measures linear (in the averages...). Despite this, the chest thump from kick drums disappears almost entirely. I can barely hear the kick in some songs As a drummer, I don't think I can just let this go. I wouldn't even say my bass is boomy elsewhere - Bass players can run up and down their scales and sound clear and defined the whole time. Any unnecessary rumble from effects or other boominess is manageable if not fully removed.

I clearly have myself a nasty room mode. I'll blame the semi-open floor plan for it being tough to fight and inconsistent left to right across the couch. What gets me, however, is that the problem is only if I'm sitting, regardless of X,Y location in the room.

I know there's a few dozen solutions out there but most are impractical or expensive. Yet, I know others have tread this ground successfully - what's helped you all? Or if not, any EQ advice that may be practical at all?

 

[RayDunzl]

any EQ advice that may be practical at all?

You want to feel it?

 

[DVDdoug]

which needed a massive bump (summed between 12 and 16db, both speakers). As mentioned, after the bump, it measures linear (in the averages...). Despite this, the chest thump from kick drums disappears almost entirely.

How big is your subwoofer? How much power do you have?

It might measure flat at low frequencies and low power but it might be giving-out when you try to get more energy out of it.

And with 12-16dB of boost you are almost certainly clipping your amplifier. +12dB is almost 16 times as much power and +16dB is almost 40 times the power!!! (Handy spreadsheet.)

You can fix a bump with EQ but when you are getting standing wave cancelation it's almost always impossible to fix with EQ. The only solution may be bass traps or maybe moving your subwoofer. (It's surprising that you're also getting an equally-bad bump at a different frequency and/or at a different spot in the room.)

I'm pretty sure the thump you can feel is below 100Hz but 40Hz is probably low-enough. Most pro subwoofers used for live music and in clubs are tuned for around 40Hz and the lowest note on a standard bass guitar is about 40Hz. That's low enough for bass you can feel, but a live kick drum may go lower. As you go lower you loose efficiency and in a large space you want as much efficiency as you can get.

 

[srrxr71]

You cannot boost to cancel a room mode.

Room treatments are the obvious answer.

However you did say it happens when you sit only. You need to change the relationship of your subwoofer location to the floor/ceiling. Or that of your seated position to the floor/ceiling.

This will take some experimenting unfortunately.

Sometimes it’s better to just leave those dips especially if they are narrow (high Q). You won’t even hear them. If they are wide then yes corner traps first. Then consider stands for the subs. Or raising your listening chair.

I don’t know what else I would do.

 

[hege]

Are your expectations realistic? Going by your signature, few sealed 6.5" drivers run from a receiver and a 12" sub does not equal chest thump, you need large mains for that and high volumes. As @DVDdoug said, with such insane boosts you are probably frying your receiver and likely clipping things. Are you sure you have properly dialled in crossovers etc..

Do you have a reference from outside your system? Lots of stuff is produced poorly too, there's no thump to begin with.

PS. It's ok to moderately boost dips, if it's the type of dip that allows it and you actually have amp/speaker headroom to do it. I use some 6dB boost around 130hz to lessen my dip, works fine and can crank 100-110dBZ no problem..

 

[Zinda]

Are your expectations realistic? Going by your signature, few sealed 6.5" drivers run from a receiver and a 12" sub does not equal chest thump, you need large mains for that and high volumes. As @DVDdoug said, with such insane boosts you are probably frying your receiver and likely clipping things. Are you sure you have properly dialled in crossovers etc..

Do you have a reference from outside your system? Lots of stuff is produced poorly too, there's no thump to begin with.

PS. It's ok to moderately boost dips, if it's the type of dip that allows it and you actually have amp/speaker headroom to do it. I use some 6dB boost around 130hz to lessen my dip, works fine and can crank 100-110dBZ no problem..

I agree, before you can expect to feel the sound, the recording has to have that included with it.

My speakers can put out some room jarring sound. I once unplugged a ¼" plug while the volume was at normal listening levels and the resulting pop scared me but not the noise it made but rather by the blast of air that hit my face from 10 feet away. During normal playback I rarely hear the deep bass that my speakers are capable of reproducing because the information is not there to begin with.

Some advice when using DSPs try it without the DSP and I think you'll find it will sound way better without it. I tried 5 DSP units and found they destroyed the sound. Little things disappeared and impact was diminished. One more thing, those test results are never worth looking at. I noticed analog testing showed way more variations in frequency amplitude while computer programs show very little variation almost like the results have been smoothed over even when none has been applied.
My system always sounds better with a tiny bit of analog EQ done by ear. Don't waste your time and $ on DSP and useless tests, it will just aggravate you and get you no where.
When I test, T-50 and T-60 don't even apply to my system there's nothing there to show. I use no add ons at all. Waterfall looks like a river and FFT graph shows a red line with green and blue waves on top and bottom. I use DIY speakers and 40 year old amps.

I don't bother testing unless I'm building a speaker and need to find the natural roll off or matching dips in sound for crossover points with each driver.