Audio Chews: the hi-fi and music community

Brain_Dead

When Brian O,Rourke of Ruark and Diesis fame set speaker up at shows, he showed me how he set them up, he stood bending over the speaker whilst playing a bass filed music and moved the speaker backward and forward from the walls until he heard a bass lift. I have tried this now often and it work very well, thanks Brian.

Monty

Yes, my problem is my speakers need to be almost 1.5m off the wall to sound good which according to SHMBO is rediculous ! The other solution was to move the sofa. That, according to SHMBO isn't happening either.
My solution is to move the whole room around but making sure SHMBO thinks she came up with the idea ;)

Docfoster

Any tips on how to speed up speaker positioning gratefully received. I find speaker placement 2nd only to tone arm adjustments in terms of time taken and annoyance caused.
Interesting technique there. Did the adjustments made when next to the speaker hold true when in listening position...?
Generally, I've found moving speakers to and from walls tends to effect bass, but also the 'separation' of distinct sounds in the music. Getting more bass has often come at the expense of a more congested and muddled sound.

Jim

Using the room boundaries to increase or decrease bass response will always be a trade off - and as Ben says will result in a congested sound if placed too close to a boundary. I find it best to allow the speakers to do only what they can. A small amount of Eq can be helpful if the frequencies are reduced. As I said before if you Eq more bass in it's not just the speaker but the amp that's having more demands made of it. Most box speakers should perform best between 1 and 3 feet from any boundaries. Damping rear and side walls to slow early reflections can be very helpful - though that's not always domestically acceptable. Speakers that the designers claim are made to work close to a back wall typically have no real bass below 100Hz or so; i.e. Kans, LS3/5A. Diamonds etc. The theory states that a speaker close to a boundary will increase the bass response by 3dB, the problem (this is Ben's point) is it doesn't just affect bass but midrange as well. HF is affected less as the higher the frequency the more it beams or squirts straight ahead - a bit of an over simplification but generally true.

In the end the only successful way to achieve more (and/or better quality) bass is to get speakers with larger cones in larger boxes. The exception here is horn cabinets which use, usually, the corners to generate more bass. But horns bring a whole other set of compromises.

Brain_Dead

Hi Jim,

In the confines of a small hotel room at show it worked well as most of the bass was sucked up by bodies, and lift wells so it was a good compromise I think on Brian's side.

I agree that nearly all small boxes roll of early, but Tannoy Buckingham did not and it worked very well on them to, OK it took four us to move the monsters, and the neighbours did complain about the low rumble caused by helicopter flying in the room .

I used Magnum A100 mono block 400W a channel, the bass made you feel physical sick.

I heard once in Somerton at Jim Watts place a folded horn under the floor of his shop, wick stuff. I bet it is still they in the cellar.

By the way who wrote the Theory?? I will read it.

coops

There is an interesting and informative loudspeaker placement guide on the Genelec website,
Keith.

Jim

I was talking ideals or 'in a perfect world' scenarios, no doubt it works. It's all a compromise and moving your box towards a boundary is just one of many. Lots of people aspire to a large listening room assuming that it will remove the boundary issue. It will but it brings plenty more issues to deal with.

I've also heard speakers that reproduce bass that does a rumba on ones's kidneys. Problem is I've never heard it real music.

Do an internet search for speaker boundary relationships, plenty of info available.

Brain_Dead

So true Jim so very true.

Thanks for search found them and reading now, thanks.

Best Col

Jim

Some of the maths can be a bit hairy but it's mostly common sense really. Enjoy the reading :)

Monty

This was mentioned on another site....
http://www.gikacoustics.com/uk_education.html

Very interesting stuff here and might be worth a go ....... I could only put treatment on the 2 corners behind the speakers and on the wall behind the sofa, not on the reflecting walls as there's a fire on one and a door on the other.....

Does anyone here use such room treatment?

uglymusic

Only life's clutter, I'm afraid ;-)

Jim

I use 3mm underlay - the kind used for laminate flooring. Ugly as sin but cheap. No one uses my room but me so I don't care. I've stuck it into the corner behind my speakers and used two layers. Works well at slowing down reflections. I'm avoiding the word absorb as I'm not trying to create an anechoic chamber. I want some reflection as it helps with ambience but too much blurs the main speaker output.

I've found that symmetry behind the speakers is also important. Try if possible to have the back of the speakers "looking", if you will, at the same environment. Mine's as close as I can get it without moving a door!

uglymusic

That symmetry aspect is a real problem in my room, as I have a large bay window immediately to the left of my left speaker. I've had stereo image problems when I've not had the Royds positioned correctly.

Alan

I cant do symmetry either, but listening nearfield does quell some problems. Particularly as my right speaker is now almost 4ft from the side wall (and almost the same from the back wall - this is helped by a useful alcove).

my left speaker is 10 - 12ft away from the right, and about another 15 from it's own side wall. It's farn fromideal, but sounding pretty decent these days.

I have no real comprehension of the math or theory behind speaker placement, but I find the subject fascinating, and would love to learn more. I had better get it right soon though, as I cant put too many more spike holes in the carpet...

Why do some (usuall smaller) speakers work well far apart - as in further from each other than to the listener - than most other speakers?

Jim

Why do some (usually smaller) speakers work well far apart - as in further from each other than to the listener - than most other speakers?

Good question. I think it's down to the amplifier/s actually. I have absolutely nothing to back this up with apart from experience.

Alan

Amplifiers, Jim. But not as we know them...

Perhaps you are right, but if I were to get those old Goodmans Magisters out of storage (with their 15" bass cones) would they work in the same position as the Royds? Thats about 12' apart and about 8' from my setee.

It would seem illogical to expect them to work there, and I might have to engage a cloaking device to hide them from my human wife.

live long and prosper...

Jim

I reckon they would work just as well.

Try it!

Alan

Jim said:
I reckon they would work just as well.

Try it!

I must do so one day. They wont last long in the front room though as they are 'aesthetically challenged'. Mind you, she lets me in...

They also need decent banana sockets put in the rear, as the have a little screw on a thread. If my amp even sees a short circuit I will be lacking a paddle, so best sort that out first. One day!
:)

Docfoster

Alan said:
my left speaker is 10 - 12ft away from the right, and about another 15 from it's own side wall. It's farn fromideal, but sounding pretty decent these days.

Farn Fromideal...?
Not heard of them. Are they an old scandanavian or dutch make of 'speaker that suffer from a bad reputation?
;-)

Alan

Ha! You mock my android phone's lack of spell check sir!

Farn Fromideal should be an IKEA range of egg cups or something.

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