How Do You Position Your Amp From The Wall?

[resonator]

I just received a new Lone Star Special 410 and loving it. It's an open back amp, so I've been trying different positions in relation to the wall in my music room. It definitely makes a difference in how the amp sounds, depending on how far from the wall it is.

How do you position your open back amp from the wall?

Res

[Platefire]

I can't stand it with my open backs right up against the wall. It makes the amps sound to tinny and takes out the bottom. I always try to put as much distance as possible between a wall. Any closer that about three feet it really starts robbing your tone. When I know I got to play right up against a wall, I use one of my close back amps. Platefire

[Veitchy]

Why does it make a difference?

[Tony474]

Originally Posted by Veitchy

Why does it make a difference?

It makes a difference because there are two sources of sound. First the obvious one of the waves directly radiated from the speaker cone(s) and second the waves reflected from the wall behind the amp, coming off the back of the speaker(s) through the open back of the cabinet. Now, as a very general rule and put very simply, treble sounds travel in straight lines while bassier tones spread out in all directions. It's to do with wavelengths. What this means is that if your open-back amp is positioned the right distance from a wall, other things being equal you'll get a bigger, fuller sound than if it's too close or indeed too far away.

Of course, in a gig situation you don't always have a lot of choice - small stages, curtains, drapes, etc. - but if there is enough available space positioning appropriately can fill out the sound noticeably or alternatively kill a boom caused by bad room acoustics.

[resonator]

So far, I'm finding the best tone when the LSS is not straight with the wall, but angled so the left side is about 14" and the right side is about 26" from the wall. the room size is 16'x13'. So it's sitting in the middle of the 13' side and angled toward, but not at the rear corner.

I bet you all were dieing to know this. LOL

Res

[blue metalflake]

All I know it always sounds better "a bit" out from the wall, and not stuck in amongst stage drapes or whatever. Never did anything more scientific on it.

[eddiewagner]

i found out tjat is has to be straight in line with the wall. i positioned my amp in a corner and it soundes really bad.

[WireLine]

Depends on the amp and (strangely) the wall...If a closed back distance from backing surafaces are less critical...if an open back, a concrete or brick wall will probably cause even the most expensive amps to sound very very bad, where as a solid wood wall (a rarity, I know) will likely cause an amp to sound better than it really is...this is one reason why recording studios cost so frakking much to build, as the walls can make or break the overall sonic signature of everything picked up by mics...

That said, I try never to run speaker cabs parallel, as this can develop into the dreaded standing wave...even just an inch difference breaking the parallel surfaces will help tremendously...

Also remember the floor is just another wall, as far as sound is concerned...and wooden floors will invariably resonate and increase bass, where concrete or brick will likely reflect highs resulting in a very brittle sound...

Advise is to do like most people do anyway - have some sort of stand (even just a chair) angled up a little and make sure there are no parallel surfaces between your speaker cab and any walls or floors around, and you should be just fine...

[Tony474]

Originally Posted by eddiewagner

I found out that it has to be straight in line with the wall. I positioned my amp in a corner and it sounds really bad.

Absolutely. Corners are murder for decent sound with waves zooming around in all directions generating a boom at certain frequencies. Often, however, with a corner stage, although it sounds bad for the players, by the time the sound reaches the audience the worst effects have dispersed and out there it sounds OK. Again, it all depends on so many features of the room.

[Tony474]

Originally Posted by WireLine

That said, I try never to run speaker cabs parallel, as this can develop into the dreaded standing wave...even just an inch difference breaking the parallel surfaces will help tremendously...

In extreme cases in some very peculiar rooms I've resorted to having the PA speakers as far apart as possible, facing each other either directly or at only a slight angle and running them out of phase to avoid frequency cancellation. Not often to be recommended but it can help if all else fails.

[Platefire]

I agree with everything Wireline said and found it to be true with the exception of a wood wall imporving the sound. Plaster/Drywall and Wood also increase highs a rob your bottom. You'll find yourself doing radical things with the tone controls to no avail.

If you like a closed back cab, then this is no issue---you can let it rest against the wall with no change.

[resonator]

Originally Posted by WireLine

Depends on the amp and (strangely) the wall...If a closed back distance from backing surafaces are less critical...if an open back, a concrete or brick wall will probably cause even the most expensive amps to sound very very bad, where as a solid wood wall (a rarity, I know) will likely cause an amp to sound better than it really is...this is one reason why recording studios cost so frakking much to build, as the walls can make or break the overall sonic signature of everything picked up by mics...

After reading this post, I moved my music room around and now have the LSS 410 sitting in front of double, solid wood doors. It's about a foot away from the doors. It sounds even better than before.

Res

[Tony474]

Originally Posted by Platefire

Plaster/Drywall and Wood also increase highs and rob your bottom.

Increased highs may or may not be desirable, depending on circumstances, but on no account should one allow one's bottom to be robbed...

[WireLine]

Plaster/Drywall and Wood also increase highs a rob your bottom. You'll find yourself doing radical things with the tone controls to no avail.

A sasd but true manifestation of today's 'home building' techniques...please note I specifically mentioned solid wood wall in my initial post...IMO plaster/wallboard walls can contribute to a sound, IF they are solid enough and filled with a substantial amount of fiberglass insulation - common studio construction techniques often suggest a 5/8th layer, then a 3/4 layer, then a 1/4 layer of drywall, with the cavity stuffed with the best insulation one can afford, with the same level of seemingly overkill on the other side of the wall.

But - chances are pretty good that most gig venues do not have more the 1/4" drywall over empty space... I know some guys who are so out-there regarding their sound they actually take a small (3 ft by 3 ft) framed and covered panel of OC 703 wrapped around a 3/4" sheet of plywood - a miniature GOBO if ou will, to place behind their amps...seen one fellow build a small 3 sided 703 GOBO and placed his amp in there...weird tactics, but very effective..

Of course this guy also mic'd his amp with a Neumann U47FET thru a rack mounted esoteric studio preamp (API)... obsessive? Yup...Worth it? He thinks so, and I'm starting to.

[Tony474]

Originally Posted by WireLine

A sasd but true manifestation of today's 'home building' techniques...please note I specifically mentioned solid wood wall in my initial post...IMO plaster/wallboard walls can contribute to a sound, IF they are solid enough and filled with a substantial amount of fiberglass insulation - common studio construction techniques often suggest a 5/8th layer, then a 3/4 layer, then a 1/4 layer of drywall, with the cavity stuffed with the best insulation one can afford, with the same level of seemingly overkill on the other side of the wall.

But - chances are pretty good that most gig venues do not have more the 1/4" drywall over empty space... I know some guys who are so out-there regarding their sound they actually take a small (3 ft by 3 ft) framed and covered panel of OC 703 wrapped around a 3/4" sheet of plywood - a miniature GOBO if ou will, to place behind their amps...seen one fellow build a small 3 sided 703 GOBO and placed his amp in there...weird tactics, but very effective..

Of course this guy also mic'd his amp with a Neumann U47FET thru a rack mounted esoteric studio preamp (API)... obsessive? Yup...Worth it? He thinks so, and I'm starting to.

The word "overkill" springs to mind. First of all, half-a-dozen people more or fewer in a venue will make a sonic difference and there's no way to control that other than playing so badly that everyone leaves. Secondly, instead of all this messing about, why not just buy a Tech 21 Trademark 60 in whatever speaker configuration you fancy and slave it up through the PA via the built-in SansAmp? Or indeed just mic up your present amp with a 57 or whatever judiciously positioned by the cone and adjust the PA accordingly.

[Clive Hugh]

Originally Posted by WireLine

Depends on the amp and (strangely) the wall...If a closed back distance from backing surafaces are less critical...if an open back, a concrete or brick wall will probably cause even the most expensive amps to sound very very bad, where as a solid wood wall (a rarity, I know) will likely cause an amp to sound better than it really is...this is one reason why recording studios cost so frakking much to build, as the walls can make or break the overall sonic signature of everything picked up by mics...

...

That reminds me, way back in the 60's and early 70's I had an amp that sounded bad, except in one dance hall, it sounded great there, never knew why till I read your post, funnily enough other good amps weren't too hot there. Wierd.
Clive

[WireLine]

I wasn't trying to pass any judgements nor offer any advise - merely passing along information. Just as no one would attempt to forcibly tell you or anyone what brand/gauge strings you MUST use, what tubes, what gauge wiring inside your amp, how many layers of finish, etc...no one is suggesting the described technique is a must have - but it is an option for those wishing to explore it...having set up a small OC 703 frame around amps in overly live situations or next to barbaric drummers, I can attest that there is some merit to it, though...but will say if one takes issue with the performer I mentioned, I'll pass along his contact info and one can bring it up with him.

As to running direct, I've done that as well...live performance is just that - live -subject to the whims and circumstances of everything from room acoustics to humidity to # of people to what those people are wearing...what I understood the OP to be is how to deal with the warts that come along with live performance - I offered some extreme examples by extreme players...

Its all about choice, information, experiences and anecdotal contributions, wouldn't you agree?

The word "overkill" springs to mind. First of all, half-a-dozen people more or fewer in a venue will make a sonic difference and there's no way to control that other than playing so badly that everyone leaves. Secondly, instead of all this messing about, why not just buy a Tech 21 Trademark 60 in whatever speaker configuration you fancy and slave it up through the PA via the built-in SansAmp? Or indeed just mic up your present amp with a 57 or whatever judiciously positioned by the cone and adjust the PA accordingly.

[Tony474]

Originally Posted by WireLine

It's all about choice, information, experiences and anecdotal contributions, wouldn't you agree?

Oh, absolutely, and I was actually agreeing that the guy you mentioned seems to have taken enormous and possibly inordinate trouble to achieve what I think a lot of people would consider only a marginal improvement. Sorry if any other impression was created, which was not my intention at all. To me it's a question of proportion - if the band is going to be resident in a venue for any length of time it's more worthwhile spending time getting the sound just so than if it's only a one-nighter, in which case you do the best you can in the time available but, as I see it, there's no real need to break your heart over it.

[kludge]

Besides distance from the wall, I find angling the amp upward some to be absolutely vital for some amps. Amp stands are really useful.

[Tony474]

Originally Posted by kludge

Besides distance from the wall, I find angling the amp upward some to be absolutely vital for some amps. Amp stands are really useful.

This is often true, and a particularly useful design is the one marketed under the "Ultimate" brand name. It has three angles of backward tilt, and the facility to attach a gooseneck to its adjustable rear post for miking up the amp. I bought a couple of them on a trip to the USA but, surprisingly, unlike most products in stores over there I've yet to see them on the U.K. market.

[WireLine]

Ya know, the best device I've ever used to tilt a small amp back is...

(drum roll please)


The plastic card holders found in bars and restaurants...fully adjustable (depending on how far you push it back under the amp), free, and infinately replaceable...

[woodman]

ashtrays work well too, unless you're in a nonsmoking bar!

[Brad J]

What's your opinions on tilt back legs?

My amp is almost always tilted back due to small stages I play, and not being able to get far enough away from the amp to hear it properly.

[sotto]

Isn't that what tone controls are for on an amp?