[kingdeezie]

Hello everyone.

So, I am completely lost. I have a 12x18 room, in which I have squeezed in a pair of GR Research LS6s. I know that the speakers are too big for the room, but I have to use what I currently have for now.

Over the years, I have moved the speakers dozens of time. I even had a professional set up the speakers, but wasn't happen then either.

I have acquired over time, a multitude of bass traps and treatments. I have all 4 corners completely trapped with GIK Tri Traps. I have the back wall treated with 3 Monster Traps across the back wall. I have a GIK 244 across the floor/wall boundary behind the listening position.

Behind the speakers I have three GIK 244s across the middle of the wall. Behind, and to the sides of the speakers, are one GIK monster trap, and two GIK 244s per speaker.

I also have GIK 244s placed along the side wall up to the first reflection points.

Overall I have something like 22 basstraps in the room, and some diffusion.

I still have problems with the bass. While there doesn't seem to be too much resonance, there is a lot of nulling. You can hear like on a bass line, it sounds sometimes like the bass "disappears" on certain frequencies. There also isn't as much definition as I would like either.

The other problem I have is vocal clarity. The vocals seem slightly out of focus and recessed sometimes in comparison to other parts of the music.

At this point I feel like I am not sure what to do from here. I don't know if I need more bass trapping, less bass trapping, different trapping arrangement.

Can a room be impossible to fix with treatments?

Should I just abandon the speakers for good, and try to get something smaller? Will a smaller physical speaker, but with similar extension just sound the same?

Any help would be greatly appreciated. 

[bladesmith]

Are you using a tube amplifier ?

[ebag4]

Have you measured the in room response of your speakers?  IMHO this should be your starting point.  REW is free and basic equipment to do the measurements is not too expensive, certainly less expensive than a couple of your bass traps.  There are quite a few threads on AC regarding REW.

Best of luck,
Ed

[kingdeezie]

I am using a tube amplifier, yes. A Manley Neo Classic 250 set.

[SoCalWJS]

Have you played with the settings for Bass on the crossovers?
Have you moved the speakers further into the room to check if it is in fact cancellation from nodes?
Definitely take measurements. Adjust from there. Once I got the bass issues reduced with my LS6's, the vocals improved quite a bit. Some diffusion can help too.

[kingdeezie]

Have you played with the settings for Bass on the crossovers?
Have you moved the speakers further into the room to check if it is in fact cancellation from nodes?
Definitely take measurements. Adjust from there. Once I got the bass issues reduced with my LS6's, the vocals improved quite a bit. Some diffusion can help too.

I have custom crossovers made by Purity Audio. The bass settings are not as clear on the crossover I have, versus the stock crossover. I have played with them a little bit, but never noticed it making a huge difference.

The speakers have been moved all over the place, using every variation of speaker set up out there. Wilson, Master Set, Vandersteen, etc, etc.

  Can't get it figured out for the life of me.

[bladesmith]

If your bass is erratic, might be your tubes. My 2 cents.

[JRace]

I would start with getting a mic and using REW to measure.
To fix the problem you may need multiple subs to even out the nodes.

Re-positioning the speakers may help.

[SoCalWJS]

I have custom crossovers made by Purity Audio. The bass settings are not as clear on the crossover I have, versus the stock crossover. I have played with them a little bit, but never noticed it making a huge difference.

The speakers have been moved all over the place, using every variation of speaker set up out there. Wilson, Master Set, Vandersteen, etc, etc.

  Can't get it figured out for the life of me.

Try doing something completely different.... If you haven't tried Cardas, give it a shot. Also try the varying odd denominators (1/3, 1/5, 1/7, etc). Have you tried both the long and short walls?

(I'm assuming you're not concerned with a huge sweet spot. My speakers are for me, so if I'm "showing them off", I let somebody else into the good chair)

Move the speakers as far apart as you can while listening to a piece you are familiar with that has a very precise center focus - usually a vocal. Keep moving them apart while they are facing straight forward until the center image goes away. Toe them in just a fraction until the center image returns (a laser pointer can help here).

This is a starting point. Measure the position of the speakers in relation to the room. Figure out what percentage of the room you are at and see if you are close to one of the odd denominator distances. Try moving them to the nearest one (as an example, lets say it's 1/5 of the room width). Now move them away from the front wall a different odd denominator (1/3 or 1/7). Adjust the toe in with the  laser so that you like the focus and the soundstage.

Don't be afraid to try something different (sounds like you've tried most things, but you never know. My room is about 15'6 x 17'6", not much bigger in area, but that 12' dimension you have is going to be tough.

Now it's time to play with the bass traps (leave the corner tri traps in place - they're great). Look at first reflection points first and put traps there (Side wall and front wall).

That's where I would start if you haven't done something similar already. I stumbled into a setup that I'm happy with that I never would have suspected - it was purely accidental. Speakers are much further apart than most would think reasonable with a bit of toe in. I have eliminated almost all of the nulls (based on readings from OmniMic)

[Hipper]

According to the link, the speaker designer says the absolute minimum distance between your ears and speaker should be eight feet.

http://www.stereomojo.com/LS6%20review/AV123LS6review.htm

If you sit too close to multi driver speakers these drivers don’t integrate properly and they won’t sound right.

If you put the speakers on the short wall you may be able to get eight or more feet away from them. You may have heard of ‘the thirds’ and ‘fifths for speaker placement. Sevenths are also possible as well as a combination of these. The purpose is mainly to reduce bass problems. You could try ‘fifths’ - speaker drivers and ears about 3‘ 7” in from the front and rear walls respectively with the speakers 2’ 5” in from the side walls leaving around 11’ 5” between your ear and speakers (if my use of Pythagoras’s Theorem is correct!). You could also try fifths on the short wall and sevenths on the long one, giving a distance of 13’ 4” from ear to each speaker. These are just starting points for you to manoeuvre around to try and get it right. Toe in comes after you’ve done this.

Forgive me if you’ve been through all this.

I would think you have plenty of bass traps etc..

I agree with those that suggest measuring. REW is the best way but it’s a lot to learn and set up. Test tones and your ears are easier if less accurate. You could download these for bass frequencies:

http://realtraps.com/test-cd.htm

Using an SPL meter may be useful too.

If you still can’t get it right try an equaliser. I use a Behringer DEQ2496 sitting between my CD Transport and DAC, and after positioning and room treatment, this helps improve things further.

[John Casler]

You haven't mentioned moving the "listening position".

If you haven't, chances are you are simply sitting in a high cancellation area.

Try moving closer, and further away in small (1") adjustments and see if you find any improvement.

Also, I have seldom heard deep bass from large Line Arrays (with smaller 6" woofers) in any room.

[guf]

couldn't you say the the vocals recessed is giving it dimension?

[richidoo]

It sounds like you've done all you can to fix the acoustic problem, so maybe the problem is coming out of the speakers. How can that be? This is the Acoustics Circle! DUH!

Maybe broken crossover or a shorted voice coil? Make sure all of the drivers are being electrically driven, not just pushed around by air pressure. Inspect the crossover circuits for connections, shorts, etc. Test the speakers' FR outside, away from reflections.

If you can use REW, do a FR to quantify the problem. Note the null freq. Then move the test mic 1 foot in any direction. The freq of the null should change. If it stays the same, it is because the speakers are "playing" the null. If  you hear the null on a specific piece of music, walk around the room listening to that passage. If you here the same exact flaw while standing different positions then it is coming out of the speakers, not caused by the room acoustics.

Use your imagination, you'll figure it out!

[Tyson]

Measure using this - it's cheap and easy to plug into a laptop to get you going.

http://www.parts-express.com/dayton-audio-umm-6-usb-measurement-microphone--390-808

[jimtranr]

You've probably already checked this--and it's the out-of-focus vocals that prompt the question--but is it possible that one of your speaker connections to the amp is wired out of phase? 

[jimdgoulding]

Well, if you've tried Cardas speaker placement and variations there of, if you've moved your chair to and fro, as well, you are about out of options.  You have too much bass energy for your room size.  Save your money, sell your speakers and some of all that treatment and invest in a smaller set of speaks.  I just couldn't live with blown up bass, personally.  Nothing wrong with your room size that a more modest size of speakers shouldn't improve.

[richidoo]

You've probably already checked this--and it's the out-of-focus vocals that prompt the question--but is it possible that one of your speaker connections to the amp is wired out of phase?

great point!  even if it looks like the right speaker cable hookup (based on speaker post colors,) go ahead and reverse the SCs anyway, as an experiment, just to make sure the internal wiring is correct. If the two speakers are playing out of phase it would create room nulls that would match your symptoms.

[JLM]

If you read Floyd E Toole's "Sound Reproduction" you'll find out that below the transition point (roughly 140 Hz for a given room) sound travels in waves (above that in rays).  Toole (worked for the Canadian Research Center and later Harmon International) explains that these lower frequencies, in a residential sized room, behave like a shallow bath tub where you move your hand back and forth along the length of the tub to make waves.  As the waves bounce off the end they return to interfere with the next waves, either adding amplitude or canceling.  Where this occurs is frequency and room size dependent, so no amount of EQ or treatments can resolve this (short of total absorption).  The solution as mentioned in a post above is multiple subs.  Search Audio Circle for "swarm".

We are conditioned to certain sound environments, the typically sized/furnished residential room (like yours) is one of them, so lots of treatments shouldn't be necessary.  In fact your room would seem to be approaching an anechoic chamber (total absorption that produces a very unnatural sound).

And sorry to say your room is a setup for echo, with length = 1.5 times width and width = 1.5 times height.  This could explain all your issues.  "Sound Reproduction" also explores the thinking behind proper room ratios and gives a suggested range based on results from several researchers.

And yes, an array should only be used far-field (much larger room than what you've got).  You'd be much happier with a pair of stand-mounted speakers and multiple subs crossed over at the transition frequency (check out Duke LeJeune here at Audio Circle for his swarm offering).

Audiophiles should really start with understanding how rooms affect sound and provide speakers that complement the room, but few do.  Instead we go for glamour and technology in obtaining impressive gear.

[kingdeezie]

WOW! Thanks everyone for the advice. There is a lot to digest on this thread, in terms of information.

The only thing I have left to do at this point, is measure it would seem. That is the most reasonable, in both price and execution, thing to do at this point in time.

It also seems to be the common running recommendation here. I am going to put an order in for that mic that Tyson posted (thank you), and I'll get started on measuring as soon as it arrives.

I'll post the graphs here as soon as I have them, and you guys can tell me what the situation is.

Thanks again for everyone's input.

[SoCalWJS]

Measure using this - it's cheap and easy to plug into a laptop to get you going.

http://www.parts-express.com/dayton-audio-umm-6-usb-measurement-microphone--390-808

I don't want to detract from this thread too much, but are you saying that this Mic plugs right into the USB port on a Laptop and works with REW? It used to be considerably more complicated than that.
Will any USB Mic now work with REW?