Cab Height / Stack Height

[fretmeister]

9 hours ago, Jus Lukin said:

 

Take two cabs to the gig? Not me- I just tilt... and go!

 

 

God, typing that made me feel very old indeed.

 

 

You'll be doing the Bass 'n' Vac dance next!

[Jus Lukin]

-

Edited March 16, 2022 by Jus Lukin

[Dood]

12 hours ago, Jus Lukin said:

 

Take two cabs to the gig? Not me- I just tilt... and go!

 

 

God, typing that made me feel very old indeed.

 

{Edited because I cant delete my own post}

Edited December 7, 2021 by Dood

[Stub Mandrel]

9 1/2" seems about right...

 

[Lozz196]

Side by side cones, science breach, you are to be exterminated!

[Bill Fitzmaurice]

Players, not necessarily. But speaker designers should know better. Sadly not all do. 🙄

[BassmanPaul]

16 hours ago, Jus Lukin said:

God, typing that made me feel very old indeed.

On January 24 I'll be 76 so trust me I know that feeling! 

[Stub Mandrel]

19 hours ago, Lozz196 said:

Side by side cones, science breach, you are to be exterminated!

 

 

18 hours ago, Bill Fitzmaurice said:

Players, not necessarily. But speaker designers should know better. Sadly not all do. 🙄

 

Ah... but it also has feet, so you can stand it on its short side.

 

The handle means that the elf won't stand on top that way up, but I could always put it on a shelf 🙂.

[Greg Edwards69]

On 06/12/2021 at 09:32, BassAdder27 said:

A bit like that horrible looking Ashdown 310 vertical cab lol 😂 

Seriously though a good 310 or 312 vertical cab rated at say 600-800w minimum @ 4 ohms but wide enough for most amp heads would be a good one cab solution 

I remember many, many years ago in my first band, we acquired a couple of Wem 4x10 column cabs for our PA. I wish I'd kept them.  They were a bugger to move around, but I bet they would have made an epic bass rig.

Edited December 9, 2021 by Greg Edwards69

[Greg Edwards69]

On 06/12/2021 at 12:58, uk_lefty said:

The Markbass amp wedge thingy solves this. I love a fifteen but need the sound pointing upwards or I can't hear any top end on the sound... Wedge to the rescue. This is what I want for rehearsals and small gigs. Big gigs will have two fifteens stacked and no wedge, but also full PA support.

I used one of those too, with my old 121H cab. It made a huge difference in being able to hear the details in the bass tone. Sitting it on a Gramma Pad seemed to help a little as well, especially on hollow risers.

 

These days I use an frfr speaker that can sit vertically or as as a wedge. I don't use the gramma pad anymore either as my Helix has an hpf.  I really ought to stick that thing on ebay!

[Stub Mandrel]

On 07/12/2021 at 15:20, Lozz196 said:

Side by side cones, science breach, you are to be exterminated!

 

At 12" centres thefirstfully out of phase "dead spot" will be at 1000 hz at 90 degrees to the speakers.

 

For a spread of 490 degrees, 45 degrees either side of centre the lowest frequency affected will be 1500hz.

 

For a typical 4×10 the lowest frequency affected is nearer to 1000hz  assuming a 45 degree either side of straight on useful coverage. That's three times the highest note of a typical 20-fret bass (E three octaves above the lowest note, 320hz). Obviously the harmonics can be affected but the real world impact of side by side speakers on bass is exaggeratedin my view.

 

For guitar or vocals I can see it's worse, or for PA with bins either side if the stage. But I think room acoustics will overwhelf such effects in practical situations.

 

I now await Bill telling me I am wro g and no dubt part of the reason will be off axis interference effects will have a modest effect even when the teo signals are not fully out of phase.

[Bill Fitzmaurice]

You're not wrong, but also not entirely correct. Most of what's heard form electric bass is midrange harmonics, not low frequency fundamentals, exaggerated as the ear is most sensitive in the midrange. Therefore the comb filtering is happening where it's most audible. Then there's the matter of horizontal dispersion, which is halved when drivers are so placed compared to vertically aligned, and here again that halved dispersion occurs primarily in the midrange that's critical to intelligibility.

[fleabag]

Makes me wonder about those new ( ish ) fangled tower PA's

 

Yamaha Stagepas,  EV Evolve 50 ,  Mark Audio Ergo  etc etc.  All sit their mid/tops on the sub on a pole.  Did they all get it wrong ?

[Bill Fitzmaurice]

In terms of placing the subs beneath the tops they did get it wrong. It's a convenient arrangement, but you can't wall load the subs and place the tops out front at the same time when you do it that way.

[fleabag]

Indeed , that is the problem with these covenient towers,  i suppose

[Bill Fitzmaurice]

One can't overlook the fact that this particular arrangement was invented by Bose, a company that has always placed form ahead of function. The rest followed suit because it's easier, and far more profitable, to give buyers what they want rather than to educate them to the benefits of better engineered alternatives.

[Stub Mandrel]

Hope you approve of this @Bill Fitzmaurice

 

😎

 

[Stub Mandrel]

P.s. those are plates in the far corner, not speakers...

[Marty Forrer]

So, with regard to sub placement, what is the advantage to wall-loading a sub? I've always put my mains on poles on the subs, am I doing this wrong?

[fleabag]

@Bill Fitzmaurice  will be along any minute, providing he isnt already drunk,  on his back,  under the Christmas tree

[Bill Fitzmaurice]

Placing subs close to walls can realize as much as 6dB higher output, from spatial loading, compared to well away from walls. It also prevents low frequency cancellation. When the distance from the sub to the wall is 1/4 wavelength the reflected wave meets the original wave 180 degrees out of phase, causing a response dip as much as 24dB deep. Another problem with subs under mains is the creation of a power alley with dual stacks, where the sub outputs alternately reinforce and cancel each other across the sound field. The only way to prevent that is to either place them together or to separate them by two wavelengths. At 40Hz that's almost 18 meters.

[Marty Forrer]

Thanks Bill.

[Lozz196]

Forgive my lack of knowledge on this @Bill Fitzmaurice but does this mean that in general it’s easier to be objective about the sound of a cab on larger stages as there’s less for the sound to “bounce around on” or is the fact that these stages are usually elevated another factor getting in the way of making objective judgements?

[Bill Fitzmaurice]

It's easier to hear the sound of the cab up close more like what's heard at a distance when there's no short ceiling or side walls on the stage. Those can cause boundary sourced low frequency null zones close to the cab, killing the lows if you're standing in one of those zones. Those zones go away the further you are away from the cab, explaining why the lows can sound much louder out in the audience than on the stage. This phenomenon lead to the myth of wave propagation, the notion that a wave can't be fully heard until one is a certain portion of a wavelength away from the source. Like most myths it was a seemingly plausible explanation for an observed result arrived at because the true explanation was unknown.

[Jack]

On 20/12/2021 at 12:58, Bill Fitzmaurice said:

In terms of placing the subs beneath the tops they did get it wrong. It's a convenient arrangement, but you can't wall load the subs and place the tops out front at the same time when you do it that way.

It just is. I know I know, wall loading subs, dispersion, has anyone mentioned power alley yet? 

 

The problem is that, in an imperfect world with competing priorities and a different stage each night, it's often the best compromise. I once convinced my hard rock band to at least stack both subs on one side of the stage with the top on top and then have the other top on the other side. Technically better yes, but it meant carrying an extra stand rather than a distance rod, worrying about the legs sticking out, having to secure the three cabinet stack with ratchet straps and then running the output of one of the subs all the way across the frontline.