[michaelv]

Hi,
 I not am sure if this is a right place to ask ,but i give it a go then.

 I am having a problem of placing speaker to get good bass from my listening position.  Here is my gears and the scenario:  Totem Forrest, plinius 9200.  I sit 9 feet from the speakers . The L/R speakers are 8 feet apart, 2 feet from side wall and 3 feet from front wall for each speaker. The chair is 2 feet from back wall.

  Whenever i stand up  in the corner (back wall) of the room, i always hear louder than i sit by listening position. However, the bass is tight and clean, just not loud enough ( i mean i don't feel it). I have bass traps at all corner of the room.

   My room is 12x14 . Does anyone has the same room size and what is your preference? Any suggestion would be greatly appreciated.

thanks.

[Daemon]

When you sit at the apex of an equilateral triangle with the other apices occupied by the speakers, you are sitting in the speakers first sweet spot (there are other sweet spots, at various ratio distances).  

In the sweet spot, you will find the mid, treble and base to be most focussed. When you move off it, such as standing and walking off axis (even a bit sometimes with very directional speakers), you will find that the treble decreases first, then the mid as you move further off, but the base will seem to increase. In fact the base is more or less the same, with a little decrease too probably, but lower frequencies travel better, and it seems that it is staying the same (and increasing in proportion to mid and treble).  

This is normal and not many speaker designs behave differently (perhaps omni-directional plasma tweeter, but I don't know as I can't afford to even smell their ozone)

As for not enough base, that's a different thing. Assuming that the speakers (which are a model I don't know) are able to do what you like, the Plinius amp if anything has a rep for being a bit warm and mushy rather than bright or forward and it's certainly not a weak amp, so I'd think that base should be fine.

How long have you had the set up? Often people coming from mid-fi to hi fi think their system is base shy, when it isn't, because they're used to loose boomy base distortion, and tight well controlled base actually makes alot less noise than that, even when it is deep and powerful.

Also some amps and / or speakers can take a week or so of solid use before they settle into their full and propper responses (usually starting bright, which makes base seem comparatively light).

If you need a subtle base addition, back the speakers closer to their rear wall by about 4 inches at a time and leave it for a while each time while you get used to what your hearing. THis will usually increase the base noise a bit, but at the expense of response and clarity (as you are sliding the speaker into its back-wave).

If you haven't had the amp and speaker combo long, I'd say just give it a while and you will get used to it, and never miss sloppy base again, and don't be tempted to buy an equaliser or some variety of magic warm cable.

Of course, it's all only my opinion and there's at least an even chance that I'm full of it.

[Daemon]

The other thing I should have mentioned is toe in / out. Just like moving your head out of the sweet spot apex changes the ratio of treble / mid / base level, so does changing the toe angle, ie firing direction, of the speakers.  If you turn them to face out as opposed to perpendicular to the back wall, the treble will increase in proportion to the base (for the same reason as it does when you move off the sweet spot). Conversely, if you toe them in, so that they face you when you sit on the sweet spot, the treble will increase in proportion to the base.

Some speaker are designed to be set toe in, and some are designed to be set perpendicular to the back wall (and these will be bright if toed in), as far as I know, none are voiced specifically to toe out. The manufacturers web site will usually tell you how they think they should go (if their manual doesn't), then your ears can tell you how you like it.

Toe will also affect the imaging and toeing in so they are firing across in front of your seating position is silly, as it is sonically equivalent to toeing out, but with added screwing up the imaging properties.

Another point to consider is that at an equilateral triangle apex position, you are in the first sweet spot, which is the near field spot for the seperation distance of the speakers, and is the brightest (mid and treble strongest) sweet spot, though usually the best imaging location too.  You can also decrease the treble relative to the base by bringing the speakers closer together, and / or moving your seating position back; putting you in a longer field position. Since you can't move your chair back, bring your speakers together will do it, but again, may decrease the apparent size of the imaging field a bit.

It may also be worth trying something as simple as putting a pillow behind your head for a listen, to see if you are getting irritating reflection off the back wall.

It's not uncommon for people to have to muck around with speaker location for hours to get it how they like it, especially if it's your first really hi end rig, so just fiddle and shuffle everything until it's as good as it seems it'll get, then give yourself time to get used to it.

I'm assuming you don't already know any of this, on the basis that telling you too much is better than a two line answer. If you already do know, please don't think I'm patronising you.

[michaelv]

Thank, Daemon. You're really helpful...   I have Plinius and Totem Forrest for a while with rote cdp. I have just updated to Ayre CX-7e for a week.  

I will try your suggestion tonight .  Frankly, the bass is really tight , not boomy at all , but a little low .

[MaxCast]

You are probably sitting in a null.  Have you taken a freuency response?

[OTL]

Just so I understand, you have bass traps and are saying that bass isn't rich enough at your listening position?  Hmmm.....

Your listening position doesn't sound as good as when you stand in the corner?  Hmmm....

Bass impact changes based upon various locations within your listening room?  Hmmm......

Sounds like you need to change your listening position, the speakers, or move the bass traps or..or...or....

So....

1) Bass impact will ALWAYS vary based upon your location in the room.  It's just simple physics and there is nothing (much) you can do to change this, other than modifying your room dimensions.  (Bass traps can help, but there's a narrow window within which they can offer help)

2) You should experiment with three things:
- speaker distance from front wall (this change is not subtle and will require you to move your listening seat)
- speaker distance from side wall (see the above)
- listening position (based upon your room dimensions the distance from your speakers to the listening seat might vary from 4' to >12' based on their spacing and distance from the front wall and the polar radiation pattern of your speakers.  To say nothing of maybe placing the speakers along the long wall, which changes everything...such a chore....!
- these changes are all interdependant, so don't loose your cool when experimenting.

3) There are no silver bullets here....it takes a bit of time and patience and moving things around.  On the upside, it is WITHOUT A DOUBT worth the end result and by a WIDE margin the most cost effective tweak ever invented.

Listen, share and enjoy!
Mike B.

[Ethan Winer]

Michael,

> I sit 9 feet from the speakers ...  I have bass traps at all corner of the room ... My room is 12x14 <

In a room only 14 feet long I can't envision how you could be 9 feet away from the speakers. That would put you very close to the rear wall behind you, and that's exactly where bass nulls (and peaks) are the worst. The drawing below shows the ideal placement in a typical rectangle room the size of yours. If you prefer not to be that close to the front of the room, you could instead sit 38 percent of the way in from the back wall. I'm also curious what sort of bass traps you have and how big they are.

--Ethan

[michaelv]

To answer Ethan:  I have 4 bass traps (4 inches thick , made of OC 703) in all corner. Each bass trap is 2'x4' and I let it sit on the floor.

Last night, i tried to move the seat away from the rear wall a bit and move speakers close to the back wall ( 2.5 feet from back wall) and i still sit around 8 feet away from the speakers. The speakers is 7 feet apart.  The bass seems to be better.

A question:  Do you mean  the ideal distance is from listening position to the wall or to the speakers because i don't place speaker very close to the front wall.

thanks.

[michaelv]

Also, How far is the speaker to the front wall based on your picture?
thanks.

[Ethan Winer]

Michaelv,

> Do you mean the ideal distance is from listening position to the wall or to the speakers <

As you can see in the drawing, the "38 percent" distance is to the front wall.

> How far is the speaker to the front wall based on your picture? <

It depends.

Seriously, the best way to do this is to start with the listening position as shown, then slide the speakers along the axes while measuring the low frequency response. Placement alone can't get a flat response, but some speaker locations will be better than others. If you have no practical way to measure the response, either do it by ear or put them where you think they look best.

--Ethan

[Daemon]

By the way, I think I screwed up back there and told you toe out increases relative treble, and toe in does too, which is crapola.

Toe out decreases treble and mid relative to base, and toe in does the converse.

Sorry it was before my first coffee and early for me.

Ethan's set up solution is a good one, putting you in the near feld best imaging position relative to the speakers, and giving you the best chance of avoiding negative room accoustical effects. If however, it's your speaker voicing that's upsetting you, it won't change much and you may not have the space to implement a ratio layout without making too much compromise in spacing between and distance from, the speakers. I agree though that you are probably a bit close is sitting position to the back wall or in fact, may be at the unfortunate spot where there is  a standing wave effect.

Trying mucking with the toe angle a bit, say toeing in less or out a little and moving your seat another foot forward and sitting something big and soft against the wall behind you (even if it's just a temporary experimental couple of pillows on the wall with thumb tacks).

[OTL]

This is SO....serious!    But yet very simple.  When it's right, it's VERY obvious

Givens:

- Every room develops standing waves which sum/null certain frequencies.

- The sum/null is controlled by speaker position, listening position and room treatment in an attempt to maximize (or minimize) the sums/nulls withing YOUR room, with YOUR equipment and YOUR ears.

- Nearfield listening only reduces the effect of early reflected sound.  Any sums/nulls in the mid-bass on down will still be present wherever in the room you happen to be listening and/or measuring in.  Bass traps can help, but can't even come close to the effect of selecting the proper speaker and listening position.

- Bass traps are not always the proper tool, especially when the speakers in question don't extend below 40-50 Hz.

A couple of friendly suggestions:

Put down the tape measure and freely move both the speakers and your listening seat.  (Have you considered the subwoofer placement techinque of putting the subwoofer at the listening location and walking around the room?  Where you hear the proper bass is where the sub goes.  Simple, no?  And absolutely correct!)

Try moving the speakers out further into the room, say about 1/3 of the length, with your listening seat about 1/3 from the rear wall.  (Your bass traps may be your enemy with this setup.)

If I was in your shoes, I'd place the speakers along the long wall 6-8 feet apart with a listening position close to the opposite wall.  This will be very close to your present nearfield distance and the sum/null will be in a much more "narrow" plane.  eg: front or back +/- about a foot or so.  If I was a betting man, my money would be on this placement.  (This accomplishes many things, the most important of which is the (almost) elimination of left/right early reflections.  Also, the arrival times from the rear wall have minimal/no effect since they arrive very close to the initial front wave.)

As for me, I've found that when the speakers are properly positioned the sound anywhere in the house is improved, not just the sweet spot.  This is much more important than most would admit.

I'm speaking as and Apogee and Spica Angelus owner, both of which are a real bitch to place within ANY space, but with considerable rewards when done right.

Hope this helps.

Listen, share and enjoy!

Mike B.

[michaelv]

Since my room is small and there are other factors like i have the door on the left and closet door on the right,  i'll be in trouble of placing first reflection point if i use the formula provided by Ethan, unless i temporarily hang acoustic panel between entrance and the wall.

So, here is what i have tried and it seems work ok to me. However, more experiment of course to get better sound and imaging:

I place speakers 7 feet apart and 1.5 ft from front wall. I currently, sit 9 ft from speakers. I will try to move the seat up to 1 or 2 ft to see what happens.  

One thing i notice that when i toe in speaker just a little bit (about 10 degree), the soundstage and imaging are pretty good. Totem actually recommends toe in  if it's really needed and my speaker (totem forrest) is designed to not toe in.

thanks all for precious suggestions. I'll keep you all posted.

[Ethan Winer]

Mike,

> Every room develops standing waves which sum/null certain frequencies. <

Yes, and additional peaks and deep nulls are caused by comb filtering reflections off the room's surfaces.

> Nearfield listening only reduces the effect of early reflected sound. Any sums/nulls in the mid-bass on down will still be present wherever in the room you happen to be listening and/or measuring in. <

Not true! I've measured substantial changes in response as low as 50 Hz over a span of only 4 inches.

> Bass traps can help, but can't even come close to the effect of selecting the proper speaker and listening position. <

This also is untrue. I even tested this.

I measured the reponse in a 16 by 10 room starting with the speakers flat against the front wall. Then I moved them out from the wall in 6-inch increments until they were 2-1/2 feet out. Then I put them back against the wall and brought in 8 bass traps and measured again. When the speakers were 18 inches out from the wall, the response was flattest. But when it was against the wall and 8 traps were present, the response was much flatter.

Of course, flatness is only half of the equation. The other half is modal ringing which speaker positioning alone cannot improve.

> Bass traps are not always the proper tool, especially when the speakers in question don't extend below 40-50 Hz. <

Bass traps do the most good between around 80 Hz and 300 Hz.

> the arrival times from the rear wall have minimal/no effect since they arrive very close to the initial front wave.) <

Spacing to all walls has a very significant affect on the low frequency response in any room!

I don't really disagree with you as much as it may sound. There's no question that playing around with speaker and listening positions have a very real impact on the reproduced response. But all such experimenting is best done by measuring. You can't do this well "by ear" for several reasons. One reason is that the key of the music interacts with the room modes. Another is that some response curves might sound "better" even if they're not flatter. For example, a dip in the "woofy" range around 200 Hz might sound more pleasing, or a peak in the fullness range around 100 Hz might seem better. But those are not necessarily flatter.

--Ethan

[jermmd]

Here's a nice site for speaker placement recommendations. At the bottom of the page are links to other speaker set up guides.

You've gotten good advice so far. It's hard to get used to the idea of bringing the speakers so far out into the room and sitting so close. It seems like all that space in the back of the room is wasted. Still, you should try it if you really want the best sound your speakers can reproduce.  The ideal speaker placement for music in my home theater unfortunately obstructs the sides of my movie screen. I've had to compromise sound quality with the best possible non obstructing placement for most of the time. When I really want to hear the system at it's best, I have marks on the rug for the ideal speaker placement. I just move the speakers to the predetermined spots.

[OTL]

I'm enjoying this way too much!   ....and do appreciate your open mind.

To beat a dead horse... , You said it yourself..."Another is that some response curves might sound "better" even if they're not flatter. "

Man, OH man...if it sounds better, it IS better.  Would you be willing to chose a placement/EQ/treatment that sounded worse and measured better?  Life is way too short for that.

Experience over time with various combinations of equipment and environments (including "live performance") does lend itself to a better "understanding" of what is "better".

On another note (aka: tangent), a few years back I sat next to the mixing board at an outdoor Maynard Ferguson concert.  At first the mix sounded like big, deep shit and was rapidly going from bad to worse.  The guy on the board kept desperately tweaking, sliding and turning.  After about 20 minutes or so he managed to dial in "the sound".  It was unmistakable and very, very, very good.  This was one proud engineer.  When he looked down at me, I was looking back at him and we were both grinning like idiots.  He had NAILED it from 40 yards away and we both could not only hear it, we could feel it.  His setting for that "sound" would not have worked anywhere else except for this particular venue, that night, that space, etc......It was magical.  The only public mixes that in my limited experience that could possibly rival this were Zappa (twice, omigod, twist 'em up) and Edgar Winter/Black Oak Arkansas at the Boston Music Hall.  Go Jim Dandy, GO!, but I digress....especially now that you know how old I must be.

The pursuit of "flat" is an impossible task.  Recordings are EQ'd, Mic's have empahsis, xover's are voiced, electronics have feedback and all rooms are different.

What you need to pursue is the best that your present combination of gear can provide.  Your equipment's shortcomings cannot be overcome.  Either it's there or it's not. Room treatment cannot make a silk purse out of a sows ear, and a flat response does not play into the fact that humans do not have a flat hearing response. (No doubt that your tweaking can sucessfully add to and improve your experience)

So, move 'em all around.  Have a ball!  In all truth, there's a small margin of possible positions within YOUR room where your speakers will sound their best.  Stop measuring and start listening.  You just might be quite surprised.

Here's grinnin' atcha...I'm going to toss back a cocktail while waiting patiently for my new VMPS RM30's to arrive.

Mike B.

[Daemon]

You guys are getting well above me, but it's good to read about and learn though, so keep the polite argument going  

One thing I can agree upon from experience is the flat response and human rolled off hearing bit from Mike.

I use my wife as my ultimate authority (bizzare I know). We had a guy come to our house back in the days when we lived close enough to anywhere that guys wouldn't charge a weeks wage to visit with home audition equipment. We wanted to audition a room correction EQ with someone who could drive it.  The guy set it up and played with it and performed a few dark rituals, then pronounced it good and flat and true.

My wife gave him a record and said, "play this", which he did; pointing out all the while how flat and clean and truely true it truly was. I sort of thought is sounded a bit nasty, and more than a smidge bright. However, my wife pronounced it utter shite, and told him that it was wrong in every respect. He responed by looking down his nose at her, and explaining to the poor wee blonde thing that ,"this maddam, is the way the music truly sounded at the recording, were you to be sitting in the concert hall, and in fact it is as near as possible to perfect with your existing equipment. Your not liking it is because you're not used to cleanly presented and truly true music, as you would hear in the live performance". To which my wife replied by politely explaining that the sound of that first violinist was in fact her, that she was present in the concert hall and the mastering studio, that she is at least passingly familiar with the sound of a truly ruly real violin, and that since you're so obviously full of it, it must be past time for you to leave with your expensive thingo.

I asked a sound tech about this, and he told me that a flat response usually sounds aweful, because highs roll off when passing through air, and ear response also rolls off. If you get it flat you've boosted it to unatural brightness, which sounds awe inspiringly yuchy. Being credulous at best, I more or less believe him.

[Ethan Winer]

Mike,

> if it sounds better, it IS better <

Okay, but "better" for one tune in one key may not be better for another tune in another key. That's the main point I'm making. You'd be there all day with 100 CDs trying to get a balanced sound by ear, because every CD track you play will have a different "best placement" for what sounds good.

This is why the goal should be to place things (and treat the room) so the system measures as flat as possible. Then you will truly hear what the recording engineers had in mind. And that will also give the best "average" to make the most number of recordings sound good.

However, if someone prefers to dial in a "smiley face" setting on an EQ to make it sound "good" to them, that is definitely their choice!

--Ethan

[Ethan Winer]

Daemon,

> I sort of thought is sounded a bit nasty, and more than a smidge bright. However, my wife pronounced it utter shite <

Yes, this is a very common reaction to systems that have been EQ'd in attempt to make them measure flat.

> a flat response usually sounds aweful, because highs roll off when passing through air, and ear response also rolls off. If you get it flat you've boosted it to unatural brightness <

I agree with this too. A loudspeaker should be flat when measured in an anechoic chamber. But attempting to use EQ to force a speaker to measure flat in most home systems is doomed to fail for the reasons you mentioned. Both of my systems measure reasonably flat (my HT is amazingly flat), but a big part of why they sound excellent is because all first reflection points are treated with absorption. Lack of first reflection treatment is a big reason that a system won't measure flat. Indeed, it can't possibly be flat because of all the comb filtering going on.

--Ethan

[mixsit]

Man, OH man...if it sounds better, it IS better. Would you be willing to chose a placement/EQ/treatment that sounded worse and measured better? Life is way too short for that.

...On another note (aka: tangent), a few years back I sat next to the mixing board at an outdoor Maynard Ferguson concert. At first the mix sounded like big, deep shit and was rapidly going from bad to worse. The guy on the board kept desperately tweaking, sliding and turning. After about 20 minutes or so he managed to dial in "the sound". It was unmistakable and very, very, very good. This was one proud engineer. When he looked down at me, I was looking back at him and we were both grinning like idiots. He had NAILED it from 40 yards away and we both could not only hear it, we could feel it.

...His setting for that "sound" would not have worked anywhere else except for this particular venue, that night, that space, etc......It was magical...

Just to add on to where I believe Ethan is going, you can look at 'reproduction' from a few different ways. I for one want (and need) as honest and neutral as I can get. This has to be the foremost consideration if one is ever to hope to come to terms with the fact that all recordings have variables between them in their portrayal of 'correct' (let alone the position you are placed in when creating and choosing these compromises in the production end).
So take the 'concert mix' example (methodology) as it applies it to your decisions on where and how to pursue 'fidelity'. If taken to the one extreme, you could decide to 'correct' from 'neutral' on a 'album-to-album basis. Naturally this could be considered extreme (perhaps more so if you believe you are a 'purist'), but something I would consider a plausible option -the addition of active eq in the chain for example.
I just feel it is very well to understand when and how, and why, you're doing which. To what ever extent, this understanding gives you the freedom to know the difference, when your going for one or the other.

Wayne Smith