Dispersion in Bass Cabs. Is it really important?

[BigRedX]

Following on from some rather heated discussions about the merits of certain bass cabs over the past few months, some of the arguments have got me thinking. In particular the question of dispersion. The physics of a lot of the advice seems to make sense - don't mix your cone sizes without cross-overs and the arguments for stacking your drivers vertically rather than horizontally, but the more I think about them, the less they seem to be relevant to real-world gigging situations.

A lot of it comes down to what we actually use our bass cabs for? Since 2010, I can recall less than a handful of times when the bass wasn't put through the PA, and all of those were in rooms so small that most of the audience would have problems getting 33° off-axis let alone 45°! Conversely, for the rest of the band to be able to hear me properly without help from the foldback, I'd need speakers/cabs with a decent 90°+ off-axis response. On most stages I'm pretty much stuck in one place, and on the bigger stages that have room for actual movement there is nearly always excellent foldback so most of the time the band is relying more on the foldback to hear my bass than it is on my cabs.

If I'm being honest with myself, my bass cabs are mostly there for two reasons - for show and bring the controls on my amp and BassPod Rack up to an easily accessible height. If I could guarantee that every gig I played had suitable foldback, I'd probably ditch the cabs and amp altogether and just bring the BassPod (or upgrade to a Helix).

Apart from bassist who regularly play decent-sized rooms without PA support, is dispersion an important consideration. From where I'm standing I can't see (hear) it!

[Twigman]

All our gigs are in reasonable sized rooms (c500 capacity) - all shapes.
We always have PA support.

We tend to angle our cabs so that they point somewhat across the stage.
We use them solely for hearing ourselves
Many of the venues don't have enough foldback channels to satisfy all of us.
I normally won't get one.
I'm normally behind the keys next to the drums.
We discovered this trick in US last year, the guitarist points his amp across the stage at 90degrees to the audience!
I point mine across the stage too.
With this setup the onstage sound is akin to rehearsals
Dispersion is not an issue for us.
The audience only get the PA sound, really
The keys uses his wedge as his only source of hearing himself.

[Bill Fitzmaurice]

[quote name='BigRedX' timestamp='1494926138' post='3299567']
Apart from bassist who regularly play decent-sized rooms without PA support...
[/quote]IME that description applies to at least 80% of bass players. Besides, having a rig with good dispersion doesn't require jumping through multiple hoops, so why not?

Edited May 16, 2017 by Bill Fitzmaurice

[Conan]

IME, most people talk about dispersion from their own perspective - in other words, how well they can hear[b][i] themselves[/i][/b] on stage, not how well the audience can hear the bass.

Our own experiences vary of course, but the vast majority of my gigs involve only the vocals going through the PA, and all the instruments relying on backline to be heard. I have used many different cabs, from a large range of different manufacturers, but definitely prefer the ones that allow me to hear myself better on stage. To date, the best ones in this respect have been made by Barefaced - a Big One and a Compact. The list of brands I have tried includes TKS, Bergantino, Genz Benz, Markbass, Ashdown, Ampeg, Trace Elliot, Gallien Krueger and Peavey. Not exhaustive, but pretty extensive.

[Phil Starr]

For me the answer is 'I don't know', but I'd like to.

I'm inclined to agree with BFM, 80% of my gigs are in small venues and what the audience hear is my back line. At the same time we know how to control dispersion and if there are things I can do at little or no cost then why wouldn't I? At the same time in an ideal world I'd want one dispersion pattern for the audience another for the band and yet another for my monitoring, then I'd need a different pattern in a different venue where the acoustics of the room have changed.

So the question for me is 'where does the sweet spot lay?' and what else would I sacrifice in a design to get better dispersion.

[EBS_freak]

I'm not entirely sure either - being able to hear yourself through your cab is one thing - but from an audience point of view, I would have thought that in a lot of typical gig venues without PA support, bass is going to be be fairly well heard (assuming you have enough power) because it's omnidirectional.

[Conan]

[quote name='EBS_freak' timestamp='1494942351' post='3299794']I would have thought that in a lot of typical gig venues without PA support, bass is going to be be fairly well heard (assuming you have enough power) because it's omnidirectional.
[/quote]

That's certainly my experience, as far as "bass" frequencies are concerned. However, I do find mid range to be rather more focused and therefore more susceptible to dispersion issues. It all depends on the sound you go for I suppose.

[EBS_freak]

[quote name='Conan' timestamp='1494946253' post='3299859']
That's certainly my experience, as far as "bass" frequencies are concerned. However, I do find mid range to be rather more focused and therefore more susceptible to dispersion issues. It all depends on the sound you go for I suppose.
[/quote]
Agreed - this is why I think the idea of having a cab to do foh duties is fundamentally flawed and going to compromise the sound that the audience hear.

If you are micing up the guitar to get around the directional issues associated with say, a guitar (which many bands don't - which is why you can't hear a balanced sounding guitar in a crowded pub unless you are standing in right of it - and then it's likely to be melting your face off), you may as well do the same for your bass - assuming that your PA can take it. I understand that not going through the PA and getting backline to do FOH duties may be more convenient - but you are always going to have a compromise in that setup.

That's why I reckon it's best to get a bass rig you can hear on stage so your own monitoring needs are sorted and leave what the audience hear to foh.

But thats just me.

[Bill Fitzmaurice]

[quote name='EBS_freak' timestamp='1494942351' post='3299794']
bass is going to be be fairly well heard (assuming you have enough power) because[b] it's omnidirectional.[/b]
[/quote]Only below the point where the baffle is one wavelength across, ie., the baffle step frequency. With a typical 410 that's at about 500Hz. Above that dispersion is at best 180 degrees. Then there's the matter of the cone diameter. Above where it is one wavelength dispersion rapidly narrows. With a ten that's above roughly 1.6kHz. Put those two tens side by side and the dispersion is more than halved compared to with one, and we haven't even touched on comb filtering, which occurs above where the driver center to center distance is one wavelength.

[EBS_freak]

[quote name='Bill Fitzmaurice' timestamp='1494949375' post='3299892']
Only below the point where the baffle is one wavelength across, ie., the baffle step frequency. With a typical 410 that's at about 500Hz. Above that dispersion is at best 180 degrees. Then there's the matter of the cone diameter. Above where it is one wavelength dispersion rapidly narrows. With a ten that's above roughly 1.6kHz. Put those two tens side by side and the dispersion is more than halved compared to with one, and we haven't even touched on comb filtering, which occurs above where the driver center to center distance is one wavelength.
[/quote]
I didn't necessarily say it was going to be a nice bass sound! I always found backline to be a compromise in some way... hence why I sacked it all off and went IEM. Leave the FOH to do it all.

[molan]

We always, always have every instrument in the foh mix. Levels obviously vary from room to room but our start point is always to try & provide a balanced mix.

Some of this is a 'necessity' because our drummer has a Roland electronic kit. This in itself is a huge advantage for smaller venues because we can 'turn the drummer down', lol.

I'm aware that at some venues a lot of the bass tone being heard out front is from my cab but we will eq for certain frequencies and add more foh where required.

This allows me to set my on-stage volume at a very similar level for every gig so I'm not screwing around with settings all the time. I think I'd miss the 'physical' volume from a cab onstage but I'm certainly not averse to the idea of going completely in-ear at some stage.

[BigRedX]

[quote name='Bill Fitzmaurice' timestamp='1494935646' post='3299699']
IME that description applies to at least 80% of bass players. Besides, having a rig with good dispersion doesn't require jumping through multiple hoops, so why not?
[/quote]

That's not my experience at all.

The majority of my gigs are small venues (under 250) but I'm struggling to recall the last time my bass wasn't DI'd into the PA. On several of the more recent gigs, I've been asked to turn down my amp to such a degree in order to get a balanced and controllable sound FoH that the bass in the the foldback has been louder than what has been coming out of my cabs.

It has got to the point where AFAIAC my rig is mostly there for show at gigs and is only really used at band rehearsals.

I'd love to be able to go in-ears but I don't see it as an option for small bands that rely on the venue's PA system.

[Lozz196]

[quote name='BigRedX' timestamp='1494954751' post='3299948']
That's not my experience at all.

The majority of my gigs are small venues (under 250) but I'm struggling to recall the last time my bass wasn't DI'd into the PA. On several of the more recent gigs, I've been asked to turn down my amp to such a degree in order to get a balanced and controllable sound FoH that the bass in the the foldback has been louder than what has been coming out of my cabs.

It has got to the point where AFAIAC my rig is mostly there for show at gigs and is only really used at band rehearsals.

I'd love to be able to go in-ears but I don't see it as an option for small bands that rely on the venue's PA system.
[/quote]

That "amp quieter than the foldback" thing has happened to me a couple of times. I`m not that fussed by it, only when I`m asked to turn down so low I can`t hear the amp or the foldback. Likewise I can`t remember the last time I played without going into FOH, irrespective of size of the venue.

[stevie]

Dispersion is a really important issue in sound reinforcement - so you do want to know that the designer of your PA system and your floor monitor gave it some attention.

Bass cabs are a slightly different kettle of fish. If I were in the OP's position, I wouldn't be much concerned by it: I can hear myself through my monitors and the audience can hear me through the PA. Job done.

On the other hand, if your monitors just run vocals, you don't put the bass through the PA, and you prefer to use a single small cab, then a cab with good midrange dispersion could make a difference to what you and your audience hear. For me, that means a smaller driver dedicated to the midrange, which gives you the added benefit of mid tones that are cleaner and clearer than you can get from a larger driver on its own (but there is more than one way to skin a cat).

Edited May 16, 2017 by stevie

[stingrayPete1977]

I've started using a single 12 on stage tilted back and a clanky eq, pre eq to the full range PA. The only solution to dispersion around the whole stage is in ears really.

[Beer of the Bass]

Even when there's PA, I do find dispersion to be an issue in venues that have a house 4x10" sat on the floor - often it'll sound great when I kneel to adjust the amp but when I stand up again I can't get it clearly audible without being too loud for the stage. A single 1x12" either raised or tilted, or a pair of 1x12"s stacked in portrait orientation seems good enough for my needs, despite not going all that high off axis. The guitarist has also commented unprompted that he can hear me better with the pair of 1x12"s, if that counts for anything.

[Roland Rock]

I can only think of one occasion in the last several years of gigging where bass wasn't through a PA (OP that was at JT Soar, and you know how tiny that is)

My priorities in a cab:

1: High quality sound*

2: Can safely handle my deeep subby pedals

3: Less than 13" deep so it can fit where it needs to under the stairs.

4: Light/Portable

5: Looks good

5: Dispersion/other


*sans PA at rehearsals

Edited May 17, 2017 by Roland Rock

[stevie]

[quote name='Roland Rock' timestamp='1495003092' post='3300268']

My priorities in a cab:

3: Less than 13" deep so it can fit where it needs to under the stairs.

[/quote]

Which just goes to show how different everyone's needs are. One of my requirements is for a cab that will fit under the piano in the dining room.

[BigRedX]

[quote name='Roland Rock' timestamp='1495003092' post='3300268']
I can only think of one occasion in the last several years of gigging where bass wasn't through a PA (OP that was at JT Soar, and you know how tiny that is)
[/quote]

I think the lat time I didn't have my bass in the PA was when we played in Mr Venom's front room:

[IMG]http://i114.photobucket.com/albums/n249/BigRedX/Dick%20Venom%20Live/1001267_10151596597111339_1619030816_n_zps06fe18c8.jpg[/IMG]

[Roland Rock]

[quote name='BigRedX' timestamp='1495016043' post='3300421']


I think the lat time I didn't have my bass in the PA was when we played in Mr Venom's front room:

[IMG]http://i114.photobucket.com/albums/n249/BigRedX/Dick%20Venom%20Live/1001267_10151596597111339_1619030816_n_zps06fe18c8.jpg[/IMG]
[/quote]

Was that in Carrington? I think a couple of my mates were at that gig.
I didn't hear any complaints about poor dispersion

Edited May 17, 2017 by Roland Rock

[Guest bassman7755]

[quote name='Beer of the Bass' timestamp='1494970478' post='3300147']
Even when there's PA, I do find dispersion to be an issue in venues that have a house 4x10" sat on the floor - often it'll sound great when I kneel to adjust the amp but when I stand up again I can't get it clearly audible without being too loud for the stage.
[/quote]

For a given driver size a bi-symetric grid arrangement (such as 4 x n) is always going to give the worst possible dispersion.

FAIK Barefaced 4 x 10 use some filtering to make it behave like a 2 x 10 at mid/high frequencies.

Edited May 17, 2017 by bassman7755

[BigRedX]

[quote name='Roland Rock' timestamp='1495020683' post='3300476']
Was that in Carrington? I think a couple of my mates were at that gig.
I didn't hear any complaints about poor dispersion
[/quote]

Yes it was. And I think bass cab dispersion is the least of your worries in room approximately 3m x 3m in size!

[Japhet]

I much prefer the sound through my cab than what comes out of the PA. Since 85% of what we play doesn't require me to go through the PA (thankfully), it's important for me to be able to hear what I'm playing, so dispersion is really important to me.

[EBS_freak]

[quote name='Japhet' timestamp='1495026517' post='3300576']
I much prefer the sound through my cab than what comes out of the PA. Since 85% of what we play doesn't require me to go through the PA (thankfully), it's important for me to be able to hear what I'm playing, so dispersion is really important to me.
[/quote]
Agreed - but it all depends on whether your audience feel the same way.

The key thing is to be able to get the sound what you want from your rig via DI or mic or combination of both to push out to the FOH. I've gone Kemper for this exact reason - if I like the sound from the kemper in my inears, it stands a good chance that the audience will hear similar through the front of house.

[mcnach]

[quote name='stevie' timestamp='1495015403' post='3300405']
Which just goes to show how different everyone's needs are. One of my requirements is for a cab that will fit under the piano in the dining room.
[/quote]

A couple of years ago or so I was looking for a couple of 112 cabs and an absolute requirement was that both could fit in the boot of my small car (A3)... and that led me to the TKS 1126 in the first place.
Diversity of people...