For a boomy room, what panels will reduce mid-bass

As mentioned earlier, placement of your speakers has a lot to do with it. Try putting the speakers 1/4 of the way into the room for each wall (for example, if your room is 10 by 12, put them at 2.5 by 3 away from the wall). If this dramatically reduces boominess, then you will know what to do.

Try GIK Monster Bass Traps. They are not expensive and VERY effective. I agree that sometimes a room is just too boomy on its own. Moving speakers and listening chair can locate a specific spot where the standing waves cancel just right, but that only helps if you sit EXACTLY in the sweet spot. Talking and walking in the room still reminds you that it is the acoustics of the room that need to be improved. ASC Tube Traps have been considered the best for many years. They are expensive, and the ones for bass are large diameter, tall and require floor space. Recently I discovered (and now prefer) "Monster Bass Traps" made by GIK Acoustics. These (and the less expensive Model 244) were designed for studios, they hang on the wall, and they truly absorb the reflections between 80 and 500 Hz better than anything else have experienced.

I have Real Traps minis and the 2' X 4' panels tighten up the bass when put diagonally in the corners behind the speakers. In my room, the corners behind the listener don't seem to have much effect. The minis do not screw up the mids and highs either. I had the mondos to try but liked just the minis better. The mondos were the Stereophile accessory/tweek of the year a couple years ago, however. Real Traps has no limit on how many minis you can put in the room at wall/ceiling/floor intersections. They claim you'll just keep getting better defined bass with added low frequencies the more you add. I'm not that crazy and my basement room with angled walls and ceiling (like a theater) sounds very nice (lively without clap echo--with great definition).

Sayhi5,
I think you need a strategy, one of which may be:
* Problem Identification - first use a SPL meter and test tones to isolate the offending bass mode frequencies. These test measurements across a wide bandwidth should be recorded in say an Excel spreadsheet and will become your 'baseline' from which to compare alternative speaker-listening position changes and the addition of acoustical treatments

* Moving Speakers &/or Listening Position - try putting your listening chair 38% of the room's length away from the back wall, assuming your speakers fire down the length of the room. Take measurements and record them. Try moving your speakers to 1/3 the room length away from the front wall - measure and record. Try moving your speakers closer together so that they are farther away from the side walls and toed in 30degrees.

* Bass Trap Placemnet - assuming you are like most folks and opt for the low cost fiberglass filled traps, their effectiveness is maximized when pulled out from the wall a distance that equals 25% of the offending frequency. For example, if the problem frequency is 100Hz then the front of the fiberglass filled trap should be out from the wall 33.9" (1130/100*12*0.25). Consider this a starting point for experimentation because walls with doors or windows cause that room dimension to be longer for acoustic purposes due to less rigidity. So if you have a door on the long wall then the width dimension will likely appear acoustically longer than it actually is, so experiment by starting at 33.9" and then moving the bass trap closer to the wall in small increments - measure and record each move. Try the bass traps in all four room corners from floor to ceiling and also in the middle of the front or rear wall.

* Buy VS Build (DIY) - building bass traps is pretty easy and is less costly than commercial products, but to each his fancy. I've built hemi-cylindrical diffusers and filled their cavity with OC 701 to act as a bass trap. This does two things - traps bass and prevents mid/high freq absorption so as not to over dampen the room. Just a thought . . .

good luck. let us know how it goes.

I too have an acoustically wayward room and for decades suffered from boomy bass which no amount of messing about with speaker positioning seemed top fix. And I love deep, tight, articulate bass.

I'd read of bass traps, but the problem lies in borrowing them to try before you buy and, with a subwoofer, floor space is limited. I also don't fancy sticking panels all over the walls.

Eventually, in the wake of the expiry of my Pink Triangle D:AC, which I couldn't get repaired, I bought a TacT pre-amp/D:AC with Room Correction, which worked wonders in the bass, though getting the midrange and treble palatable is a challenge and a half. Though I still have it after six years and on many but by no means all albums manage to obtain great results, I'm not sure I'd recommend it. It's just too much of a trial to get right.

However, the Lyngdorf RP-1 RC unit is designed to go between an analogue pre- and power amp (or, with an integrated amp, in the tape loop) and is reportedly very good. It may not have the endless adjustability of the TacT (which some have said may be no bad thing), instead offering a choice of six factory preset voicings. Reviews indicate that most people seem to be quite happy with the Neutral voicing. As well as having a less overtly digital sound than the TacT (a devil to iron out), it also incorporates an electronic crossover to facilitate use of a subwoofer or two.

It isn't a D:AC, accepting and outputting only analogue signals with, reportedly, minimal influence, so you won't need to ditch any of your existing kit. As an alternative to wall panels and bass traps, it's certainly worth investigating.