Getting your cab off the floor.

[orskard]

At practice today, i put my avatar 2x10 sideways on top of my hartke combo 1x12.

i was at least a 1/4 turn less on my volumes than i normally am. all just by raising up my speakers to ear level. i had the hartke on and then turned it off and i couldnt tell a difference so i left it off but kept my avatar on top of that.

how do you guys raise your amps? i know there was a post about this but that was more, tiilting them, not lifting them.

 

[MJ5150]

i leave mine on the ground. it sits on casters. until i have a good reason to raise it up, it will stay down there.

-Mike

 

[Eric Moesle]

ATA flight case that holds the cab. When you get it to the gig, you remove the cab and place it on top of the case. Elegant, efficient.

 

[billfitzmaurice]

The problem is that low frequencies require the assistance of reflections off the floor for maximum extension and power, while high frequencies travel in a straight line. There are a few ways to address the situation. The first is to move your ears to your knees. If that's not viable for you then tilt the cab back so that you maintain floor coupling while aiming the speakers at your head. Ideally you would have a sub/midbass set up, the sub on the floor, the midbass at ear level above it. Whatever you do if you have a 2x10 never place it horizontally; multiple speakers should always be vertically aligned.

 

[andruca]

The problem is that low frequencies require the assistance of reflections off the floor for maximum extension and power, while high frequencies travel in a straight line. There are a few ways to address the situation. The first is to move your ears to your knees. If that's not viable for you then tilt the cab back so that you maintain floor coupling while aiming the speakers at your head. Ideally you would have a sub/midbass set up, the sub on the floor, the midbass at ear level above it. Whatever you do if you have a 2x10 never place it horizontally; multiple speakers should always be vertically aligned.

Yes, I noticed this a few days ago. After months of using my Peavey combo tilted back against some wall (at small gigs with no PA for bass) I noticed that not only it sounds better on its feet as it is meant to be, but, contrary to what I previously thought, I hear it way better in its natural position!

ANDRUCA

 

[pickles]

Having your cab off the floor changes the sound dramatically. It will seem punchier and have more aparent volume (since its pointed right at your head), and less low bass since you loose the coupling/reflective effects of the floor. You might really like it, you might not.

Just using casters changes the sound.

 

[basicallybass]

My cabinets, when I use them...are always directed right at my chest and off the floor. My cabinets are for me...not the audience, and not the rest of my band. ---> that's why they have a quality monitor or two...then THEY can adjust how much of me they want or need. Subs are for shakin' the floor if that's what floats your boat. If you're using your cabinets to supply the bands 'umph'...you WILL in the years to come regret that kind of sound pressure levels. Ultimately, try to sell your bandmates on using quality in ear monitors. Let the audience go deaf, but lay your head on your pillow that night minus the amplifier ringin' in your head!

 

[Petebass]

how do you guys raise your amps? i know there was a post about this but that was more, tiilting them, not lifting them.

I try to use 2 speaker cabs where possible because I too like having the sound somewhere near my ears.

When I only use one cab, I use a metal speaker stand that both elevates and tilts the cab back a little bit. The height is adjustable. In the past I've also used milk crates, the venue's furniture, the drummer's hard cases, whatever.

I realise I'm probably losing some floor coupling in the bottom end but I don't mind. I think it's a better option than blowing the best part of your sound through your legs, thus playing louder than you would normally have to, blasting the crowd and plastering your sound guy up against the back wall, but not before he removes the bass from the FOH mix......

 

[Esquillama]

Whatever you do if you have a 2x10 never place it horizontally; multiple speakers should always be vertically aligned.

I'm not sure I get what you mean here. What about all those companies that specifically design systems that are stacked?
I use a 1x15/2x10 speaker set up that was designed by the company to have the 2x10 stacked horizontally on top of the 1x15. Are all these manufactuers telling people to use their speakers incorrectly?
In other words, could you clarify what you meant by "multiple speakers should always be vertically aligned"?

 

[basicallybass]

Its been my experience that the coupling effect changes the color of the lower frequencies...and it's dependent on the venue and stage. Lifting the cab off the floor has allowed me to keep my tone shape more consistent from gig to gig.
An added note...I like the Gramma Aulex as another viable option.

 

[The Golden Boy]

You really do hear the cab if it's off the floor. You can entirely change the stage character of your rig if you have two cabs and reverse what you stack on top of what. I used to use an SWR Triad with a Goliath II. For years I always put the 4x10 on top of the Triad, because that's the way it should be done, right? One day I decided to put the Triad on top. That was the day I found out that I REALLY love 15's.

 

[Petebass]

I'm not sure I get what you mean here. What about all those companies that specifically design systems that are stacked?
I use a 1x15/2x10 speaker set up that was designed by the company to have the 2x10 stacked horizontally on top of the 1x15. Are all these manufactuers telling people to use their speakers incorrectly?
In other words, could you clarify what you meant by "multiple speakers should always be vertically aligned"?

I think bill is suggesting this because it makes for a higher stack and therefore puts the top speakers closer to your ears. I know two bass players who use a couple of 2x10 cabs. They used to stack them horizontally but have switched to vertical, creating a "tower of 10's". They both claim they can hear themselves better now.

Call me picky but I like having the high frequency horn at the very top. The problem with doing it this way is that it most 2x10 cabs have the horn in between the 10's, meaning that the vertical stack often ends up with a 10" speaker at the top instead. It's not a big deal, but probably worth a mention.

 

[alexclaber]

In other words, could you clarify what you meant by "multiple speakers should always be vertically aligned"?

Dispersion. Google "line arrays".

Alex

 

[billfitzmaurice]

Are all these manufactuers telling people to use their speakers incorrectly?

Yes. Multiple drivers in a cabinet (or multiple cabinet arrays)should never be mounted side by side, but always above one another. Arraying either drivers or cabinets side by side hurts dispersion on the horizontal plane; vertical arraying enhances it.

Blame Leo Fender for the fact that 99% of the multiple driver cabinets made are improperly designed. Leo Fender was not an audio engineer; when he started building speaker cabs with more than one driver he placed them side by side because it looked better, matched up with the head unit better in a combo, and because he didn't know it was wrong to do so. Unfortunately it was his standard that became accepted as the norm which remains to this day.

 

[Luckydog]

Bill,
Not doubting your statements about vertical alignment but would like more confirmation regarding the science behind it. I checked your website and don't see any credentials to back up the engineering designs that you market. Please don't get me wrong, I'm not being a smart-a**, but I would like to understand more about why what you say is so.

 

[IvanMike]

line arrays are definitely the way to go. Apart from googling, almost every article i've read on pro audio reccomends doing it this way and backs it up with physics. The side by side arrangement looks cool, but that's about it. Aguilar has doen a good thing arranging the 4x12 vertically. Doing some experimentation and dhearing someone else play a rig of two 2x10 cabs arranged horizontally and then vertically at a venue can be a real eye(ear) opener. I try to use multiple cabinets for the best of both world in terms of maximizing bass reflecting off the floor and having a second (or third) cabinet nearer to my head.

 

[LarryO]

I'm not sure how you guys are going to anylize this but This set up sounds good to me so I have my amp on top of a 2x10. I had an old combo amp laying around and the dimentions wouldn't allow me to sit it underneath th 2x10 so, I took the amp out of it, repositioned the port and pointed the cab straight down. I have it all sitting on a frame with casters, so the 15 is actually about 6 inches from the floor. It sounds good to me, and shakes the ground......Anyone care to comment on this set up?

 

[billfitzmaurice]

Not doubting your statements about vertical alignment but would like more confirmation regarding the science behind it. I checked your website and don't see any credentials to back up the engineering designs that you market.

Credentials wise I'm a contributing editor with AudioXpress magazine (and prior to that Speaker Builder), have authored over 40 magazine articles and one book on loudspeaker design and other audio topics, have 40 years of professional experience playing electric bass, own an audio consulting firm that counts among its clients the 6,000 seat Meadowbrook Performing Arts Center, and am a full member of the Audio Engineering Society.

Technically speaking when one is exposed to sound waves emanating from two or more point sources they arrive at the listener from those sources in various degrees of phase, the differential of which being determined by the relative distances between those sources and the listener. Positive phase relationships result in augmented response (peaks) while negative relationships result in diminished response (valleys), the sum total of which results in response that is a series of peaks and valleys referred to as 'comb filtering'.

As an example, two drivers when listened to with a twelve inch difference between their centers and the listener's ears will have a null in response where that twelve inch path differential is equal to 1/2 wavelength (565 Hz) and all the odd multiples thereof, and a response peak where that differential is equal to 1 wavelength (1130 Hz) and all even multiples thereof, with irregular response in between the two extremes. As one moves from side to side in the horizontal plane and the relative distance from multiple point sources to the listener shifts so does the frequency of the response peaks and valleys;the frequency response of the system is therefore different for every person in the audience depending on where they are located.

However, if the radiating sources are vertically aligned then the relative distance from their acoustic centers to the audience on the horizontal plane remains constant, and there is no comb filtering of the system response.

This phenonmena is one that the average audio engineering student learns about two weeks into his first semester.

 

[Luckydog]

"As one moves from side to side in the horizontal plane and the relative distance from multiple point sources to the listener shifts so does the frequency of the response peaks and valleys;the frequency response of the system is therefore different for every person in the audience depending on where they are located."

Bill,
You explained exactly what I was trying to understand. Thank you for laying it out so a lay person like myself can better know the whys. I have absolutely no experience in audio engineering, and this is a great piece of information to use in my setup. I guess there were pioneers in speaker/amp design who set the standards we use today, but I wonder why this frequency response phenomenon isn't more widely understood and considered in current audio design.

 

[billfitzmaurice]

I wonder why this frequency response phenomenon isn't more widely understood and considered in current audio design

It's called 'Marketing'. You have to provide the marketplace with products that are familiar to the average consumer. Anything out of the ordinary has dubious prospects for success. Today's musical instrument speakers are not significantly different in their look than those that Leo Fender and Jim Marshall set the standard with some 45 years ago. Leo was a woodworker, Jim was a drummer, neither had any training in loudspeaker theory. The cabinet designs they came up with were arrived at through intuition, and unfortunately in the realm of loudspeaker design intuition is usually wrong. In the high end of pro-sound where the customer is a trained professional who knows what's what you don't see too many speakers being sold that aren't properly engineered, but at the level of the average musician who has no education in audio theory what mainly sells is what looks good and offers the most watts for the dollar. Offering a better engineered product that won't sell because it doesn't look right is a limb that you won't see many manufacturers willing to climb out on.