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View Full Version : Help an amateur with speaker (and listener!) placement



Peter Galbavy
02-10-2009, 09:26
I am having a mental blip and any experience and advice from those who invest vastly more time and money in this that I do would be greatly appreciated.

The room (I can't draw, so I've tried to describe):

The room is my rear reception / dining room that is now the "day room". It's 4.5m x 3.5m x 2.5m (LxWxH - give or take 15cm). At one narrow end is a large pair of French doors, double glazed. The opposite, internal wall is plain with a radiator about the same width as the opposing French doors. Then on the two longer sides are - on the left when facing the garden - the internal door, a large IKEA bookshelf unit (the one with 5x5 25cm holes) and a small internal wall coming about 50cm into the room for the last meter or so. Opposite is the unused fireplace and the two alcoves filled with CD shelving built recently by your truly - and a fine job I did for once!

Got that ? No ? Sorry. OK, it's typical semi-detatched reception rectangle :)

Now, new Focal 826W floorstanders and a Caiman (new Rotel 1572 amp tomorrow!) means I want to set this up right. The Focal manual (http://www.focal-fr.com/catalogue-docs/EN/6/files/2335.pdf) indicates that the listener should be in a max 10-15 degree off-centre cone from the tweeters, 20-30 degree total. The also have front and bottom ports - no rear.

I was mostly happy with just putting them in place of the old speakers, about 2.4m apart, 30cm from the back wall / door frame, imaging was good but I wasn't sure it was the best I could get. Tried toe-in with only minimal effect. I was mostly sitting centered but outside the equiliteral triangle - maybe 2.5m away.

Then I tried them long-ways round the room, placed in front of the CD shelves (equipment infront of fireplace) maybe 3.5m apart and my seat about 1.5m from the center line. I lost *all* imaging. Vocals sounded stretched all over. Toe-in helped a little but not much. I then drew the speakers back together, do that I once again sat outside the triangle and instantly "voila!" I could point to the singer :)

What I am asking ? For guidance please... I *think* I understand the idea of near-field speakers, and these are NOT near-field speakers. I am mostly happy with moving the speakers back where they started but I am somehow worried I am losing "width" of soundstage - but imaging is important to me from most of my music.

Please feel free to "talk down" to me using baby words. I know enough to be dangerous, but I know I have lots to learn...

hifi_dave
02-10-2009, 10:19
You appear to be doing all the right things. Ideally, the speakers should form the base of an equilateral triangle and you sit on the tip or just a bit further away from the tip.

The speakers can be toed in towards the tip, which usually gives a brighter sound with sharper imagery. The further you toe them out gives a wider sound stage but also slightly wider images. You can also toe them right out beyond facing straight ahead which looks a bit strange but may help with bright speakers but does make imagery vague.

So, you just move the speakers around to get your desired effect and also try the layout in different places in the room. There is nothing fixed. You might even like to try some extra damping behind the speakers like curtains or a blanket or duver just to gauge the effect.

Good luck.

Peter Galbavy
02-10-2009, 10:41
Thanks. When the next round of money allows I intend to replace the current unlined curtains with some serious heavy things - which I like for the aesthetics as well as the potential audio qualities.

I forgot to mention that I have a couple of home-made L shaped sound reflection panels (Wickes version of Rockwool in a wooden frame with a white/cream fabric cover) that used to live over the plasma when it was in another room. These will go on the ceiling at the first reflection points once I get settles on the position of the speakers. Shame they are L shaped, but TBH they will be fine I expect.

hifi_dave
02-10-2009, 11:06
Bl**dy heck, you've got it all covered. Lined curtains, L-shape sound absorbent panels, seems like you should be posting here not asking questions.:lolsign:

Peter Galbavy
02-10-2009, 12:05
:-)

I have spent more time with my nice AV setup and so have done lots there - mainly reading forums and websites and playing. Now that I am returning a touch more seriously to 2 channel music I want to get it right.

One side effect of my speaker placement checking and questioning and testing is that I now realise that my 5.1 system is wrong - the fronts (Focal 816W - the next model down) are far too wide apart. I might have a play there later, but redoing Audyssey and all that stuff takes a suprising amount of time :) And moving the black ceiling mounted reflection panels is also a non-trivial task. Phew.

mmar
02-10-2009, 15:36
always worth pulling further into the room and closer together , i have found even small movments in these area,s can have massive affects on soundstaging and overall tonal balance

speaker and room interaction is a nightmare and can make or break any set up well worth the effort to get right lots of time and patience req,d

have fun !

Marco
02-10-2009, 15:40
Hi 'mmar',

Welcome to AoS. What's your first name and where are you from? Could you please pop into our welcome area and introduce yourself and your system? We ask all our new members to do this - thanks :)

Marco.

hifi_dave
02-10-2009, 16:56
Marco, you're so on the ball. No one sneaks in without you getting to him pretty smartish. :eyebrows:

Peter Galbavy
05-10-2009, 08:39
OK, thought I should follow-up with a progress report.

I may have mentioned this, but it's as a summary; I was very unhappy with the speakers firing down the long axis of the room so I moved things around. When the speakers were wide apart to the point I was inside the eq. triangle it sounded wide but completely unfocused. Then I brought the speakers in so that I was just outside the triangle, it was good but far to narrow a soundstage. Toe-in didn't help much either way.

Yesterday I finally mounted my old L-shaped reflection traps on the ceiling, in a diamond shape around the lights, let's see if I can ASCII art this:



\ / <- speakers
< * > <- traps and light fitting in middle
ME



I started with the speakers still near each other (1.5m - 5 ft-ish) and it was instanly better, but I though I would now widen the soundstage a bit to see how things go. I roughly lined up the speakers with the line of the traps. Bit of minor adjustment and toe-in later and, literally, Barb Jungr was singing Bob Dylan songs inside my skull. A little too 3D, but much much better.

I am theorising, with a minimal math background, that when the speakers are further apart the low height of the reflective ceiling just manages to cause early reflections at the important frequencies, as the the path from speaker to ear is just close enough to the speaker - ceiling - ear path. The closer the speakers are to me, the listener, the "further" the ceiling is as a proportion of the path and so have less impact. The traps just capture enough of the mids and highs to make the ceiling reflection vanish. Just think, tweeters 1m from the floor and the ceiling is so only 1.4-1.5m above them - a quick bit of pythag. say that for a 1.5m delta to the ceiling the following reflective distance exist:


Tweeter/Ear Tweeter/Ceiling/Ear Diff
2m 3.6m 1.6m
3m 4.24m 1.24m
4m 5.0m 1m

Not sure how the difference in distances affect which frequencies and their harmonics (1m is about 340Hz I think) but whatever, it makes a difference.

A few test tracks later, including the Choral from Beethoven's 9th, and I think I am approching a result. I still really want to listen long ways down the room, but now with the traps in place (they line up in both orientations almost perfectly, being centred around the lights) I will try that again next weekend. More listening as-is required now.

Thanks for all the help and pointers. I will gather a stock of URLs where I have done more research too, but for now this is a good one:

http://www.tnt-audio.com/casse/waspe.html

Peter Galbavy
10-10-2009, 16:16
Getting there... one more piece of advice please:

Centre imaging is not excellent, but the overall soundstage seems to lobe around the speakers. I get a good central vocal or instrument but then much of the rest sounds like it's directly from the speakers.

I am guessing - going to try some more - that I need to bring the speakers a little closer together, but insights and experience appreciated.

Beechwoods
10-10-2009, 16:26
Coincidentally I was looking at some speaker positioning stuff this morning, and came across the following intro; which I thought quite a good write-up. The other links at the bottom of the article are also good.

http://www.gcaudio.com/resources/howtos/speakerplacement.html

I'm currently having a play with some cheap 'room treatment'. Will report on what I find...

Mick Parry
10-10-2009, 16:58
Chaps

The best advice for Peter is to ignore advice (except mine) and all he has to do is position his speakers around a few inches at a time until he has got it right. He can position in and out from the wall, he can position the distance they are apart and then bugger about with toe in. Job done.

If he wants to become a real sad nerd he can then go to the next stage of madness and mess about with dressing his speaker cables but that is a different subject entirely.

Regards

Mick

Steve Toy
12-10-2009, 11:04
Another top tip from Mick!

Peter Galbavy
06-11-2009, 12:56
Sorry to bring this thread back to life again but some might be interested in what happened next...

I could not, under any circumstances, get these speakers positioned right. Something was wrong. Last weekend I bit the bullet and did something I should have done ages and ages ago. I brought in the 816W's from the TV room and put them next to the new 826W's. What a difference. After lots of cable swapping an listening I came to the even more clear conclusion that something was wrong.

Next I moved the 826W's to the TV room and let the Audyssey room correction test them, It founf *both* has phase errors - now normally, the center, satellites and sub in a 5.1 system will have their phases compared to the fronts so I am guessing that Audyssey found there was a phase shift between some specific frequency ranges. Swapping the +/- inputs on both speakers made the message go away, which got me even more confused. They still sounded not-quite right even then and the Audyssey graph showed a complete lack of the trims applied around 80Hz which was applied to the smaller speakers in the same room - something is eating my bass too!

I am thinking that somehow the cross-overs are wired wrong - I checked the tweeters and mids and the cables match on both left and right with no obvious misconnections.

Conversely, the 816W's in the 2-channel room are doing wonderfully and are now back in the original location I wanted the new speakers inthe first place and sound fine. Not done a huge amount of imaging testing, but I will leave that for later (see below).

Long and short of it is that Focal are going to bring me a new pair and do a straight swap in the next week or two. They were surprised and will investigate once they get these back to the office.

Conclusions: (1) Trust my own ears and (2) it's not the fact that there might be a problem, it's how a company deals with it that matters - and in this case it's going well so far.

Once I get the replacements I will post a follow-up.

Peter Galbavy
23-11-2009, 22:31
As I threatened, an update. Mark from Focal brought down a new pair of 826W's to replace the pair I was suspicious about. We spent a short while unpacking them and putting them in a rough location next to the 816W's I used to confirm the old pair were not quite right. What a difference!

I have not idea what was wrong with the first pair - and not just one of the two, but both - but these are spot on so far. can't go too loud, it's late, but I will crank it up once the neighbors are out later in the week.

Mark is going to test the old pair and I really want to know what was wrong. I suspect, based purely on intuition, that the mid drivers were soldered arse-about-face on the cross-over end as the spade connectors were the right way 'round on the drivers...

Again - trust your ears!

Alex_UK
23-11-2009, 23:01
Pretty fab service from Focal - well done chaps!