Mic'ing bass amp for live shows?

[JimmyM]

+1

And nobody talked about the coupling effect in a 8/10 that will not be capture by a mike it front of a single 10".....

That's because it's irrelevant. Whatever I get out of the cab ALWAYS comes out of the mic as long as the mic is able to reproduce those frequencies. If it didn't work, nobody would do it.

 

[akaTRENT]

That's because it's irrelevant. Whatever I get out of the cab ALWAYS comes out of the mic as long as the mic is able to reproduce those frequencies. If it didn't work, nobody would do it.

This is why they call him jimmy. Now if only bob was here to supply a funny story complete with epic burn...

 

[fokof]

That's because it's irrelevant. Whatever I get out of the cab ALWAYS comes out of the mic as long as the mic is able to reproduce those frequencies. If it didn't work, nobody would do it.

Damn !!!

All those years carrying 8/10 for nothing when I could have done it with only one 10".......

Geez thanx !

EDIT: you could send a letter to all those companies designing line array system , maybe they too , can do it with only one driver......

 

[akaTRENT]

Damn !!!

All those years carrying 8/10 for nothing when I could have done it with only one 10".......

Geez thanx !

EDIT: you could send a letter to all those companies designing line array system , maybe they too , can do it with only one driver......

Good luck hearing a 1x10 on stage. even with monitering.

 

[JimmyM]

Damn !!!

All those years carrying 8/10 for nothing when I could have done it with only one 10".......

Geez thanx !

EDIT: you could send a letter to all those companies designing line array system , maybe they too , can do it with only one driver......

Boy oh boy! You're going mental over this. It just galls you to no end that someone else likes something you don't like. I shouldn't reply to you because I fear for your sanity if I do , but in the interest of edumacating young Trent to the ways of old (which are still in use to this day by the top names in the business), I'm going to.

So the line array thing you bring up is totally irrelevant to this discussion. Obviously a lot of drivers will sound bigger than a single 10". We are talking about how a mic is able to pick up the sound of a cabinet without needing to mic every driver and port, and your reference to line arrays is neither here nor there to the discussion.

OK, so the mic works...there is tons of recorded documentation as well as empirical evidence from listening to a lot of popular recordings where the amp was the only source and the cab was close mic'ed. Beck's album "Sea Change" is a recent example. All done with a B-15R close mic'ed with a FET 47. There was nothing missing. Yes, with your usual Shure vocal mic, a DI blended with it was nice because it gave you some more bottom end, but with my Heil it's unnecessary. Especially on a sealed cab where every driver sounds just like the other.

As for the port frequencies, most of them come out of the driver anyway, and what few frequencies that are only reproduced by the port find their way to the mic because they're omnidirectional. That's what a mic does. Sounds hit its diaphragm, and the mic reproduces them for recording or broadcast or live sound. So yes, a single mic pointed on a single driver on an 810 can easily reproduce the sound of the cabinet in the PA. I do it all the time, and anyone who thinks I can't is welcome to come to a gig and watch me do it IN YO FACE!!!*

* Or maybe not. I'm getting a Type 85 for my birthday, so I'll probably be speaker DIing and blending it and a mic for a while unless I decide on one or the other.

 

[fokof]

I've been in this buisness for over 25 years now and the only way I've seen (and heard) a miked 8/10 sound close (not exactly) to the reality is in a controled environement (studio , not live) with close and distant miking technique , with people with "loads" of equipement and time to do job right.
When you "close mike" an 8/10 , you get the tone & grit of the amp ,for everybody (me included) it's good enough , but you CAN'T get the coupling effect , your mike is too close to get it. Even a distant one does not capture the whole thing , the pressure you "feel" with that monter on your back. Impossible to capture & reproduce. It's a lifetime quest.


Please read my answer #95 again and your answer #101.
By reading that answer, what I understand is that your saying that there is no coupling effect in an 8/10.


PS:The alusion to line array was a sarcastic comment on an everyday application of coupling effect.

 

[greenboy]

Proximity effect of many mics does a lot what driver acoustic coupling does anyway. Not that it's really needed if EQ facilities are decent, since the response curve of the cab - any cab - is not necessarily what's needed in the FOH mix.

Perhaps you mistakenly refer to the comb filtering an 810 makes. One can only reference that in an acoustic environment by changing their listening position. That's also partly what mic placement is all about: finding a position that represents what parts of the spectrum one wants to highlight or minimize.

Your line array allusion is misplaced since a good line array exhibits coupling further up into the spectrum than what is found in a bass cab where the drivers are not shaved-frame close, nor of smaller diameter, to get closer center-to-center geometry and higher beaming points.

 

[TL5]

I've been a proponent of the DI since the early 80s (there's a story but I'll spare you).
I work full time as an audio and video engineer. If a bass player (or anyone for that matter) wants a mic on the cabinet instead of a DI, it's no issue.
Either work just fine for me.

The only challenge I run in to is when the stage volume gets too loud. This can happen in either scenario. Keep your stage volume workable, and DI or mic - whatever.

As for mics. I've not used the Heil mic, but it sounds promising.
My favorites are the EV-RE20, the Shure SM7b, or a modified SM57 (Terry Manning TapeOp mod from a couple years ago). I see the Senneheiser 421 used frequently as well, although i haven't.

 

[JimmyM]

Well, the bottom line is that either a DI or mic works just fine, and if I want a mic, I'm not letting any soundman get in my way

 

[greenboy]

Well, the bottom line is that either a DI or mic works just fine, and if I want a mic, I'm not letting any soundman get in my way

Careful - with the state fokof is in he's likely to hire an army of big bruisers who toss anyone aside who isn't wearing the stage badge ; }

 

[JimmyM]

Careful - with the state fokof is in he's likely to hire an army of big bruisers who toss anyone aside who isn't wearing the stage badge ; }

Fortunately, he's on the other side of the world, so I dodged a bullet there...unless he's rich enough to not care about how much money it would cost

Also, one thing that hasn't been addressed for stage is that ambient signals from the cab are also picked up by the various vocal, instrument, and drum mics on the stage, which also enhances reproduction of the cab onstage. I play at low enough levels to where that would be kept to a minimum, but it still happens.

 

[greenboy]

Also, one thing that hasn't been addressed for stage is that ambient signals from the cab are also picked up by the various vocal, instrument, and drum mics on the stage, which also enhances reproduction of the cab onstage. I play at low enough levels to where that would be kept to a minimum, but it still happens.

Actually it degrades it more than enhances it. Part of the problem with mic bleed in any direction from any source is that it is not time aligned with the actual signals at the source; ie the mic at the 810 is almost instantaneous at picking up the 810 (relatively speaking), while the other mics also picking up the 810 are picking up the signal after it has traveled through air n feet to where they are, each of them differernt. And some of that travel is also likely further degraded by being reflected path travel being mixed in with direct travel. Since those are at the relatively slow speed of sound and not the near-light speed of a signal traveling down wire, there are real phase/time issues.

It makes a mess, and the less of it the better.

Actually the principle outlined above is why it's cool to put a delay on PA mains so that it's coincident with backline enclosures plane. That way people hearing both the PA mains and the backline are hearing them arrive at about the same time, not so time smeared.

 

[fokof]

Fortunately, he's on the other side of the world, so I dodged a bullet there...unless he's rich enough to not care about how much money it would cost

Be carefull , I'm closer than you think !

 

[fokof]

Perhaps you mistakenly refer to the comb filtering an 810 makes. One can only reference that in an acoustic environment by changing their listening position. That's also partly what mic placement is all about: finding a position that represents what parts of the spectrum one wants to highlight or minimize.

Agree.
But live it has to be close miking, or else , you open the door to all the leak from other sources.

Your line array allusion is misplaced since a good line array exhibits coupling further up into the spectrum than what is found in a bass cab where the drivers are not shaved-frame close, nor of smaller diameter, to get closer center-to-center geometry and higher beaming points.

It was a general alusion of what coupling does in general since I was told there was no coupling effect in an 8/10 . (answer #106)

 

[JimmyM]

Actually it degrades it more than enhances it. Part of the problem with mic bleed in any direction from any source is that it is not time aligned with the actual signals at the source; ie the mic at the 810 is almost instantaneous at picking up the 810 (relatively speaking), while the other mics also picking up the 810 are picking up the signal after it has traveled through air n feet to where they are, each of them differernt. And some of that travel is also likely further degraded by being reflected path travel being mixed in with direct travel. Since those are at the relatively slow speed of sound and not the near-light speed of a signal traveling down wire, there are real phase/time issues.

It makes a mess, and the less of it the better.

Actually the principle outlined above is why it's cool to put a delay on PA mains so that it's coincident with backline enclosures plane. That way people hearing both the PA mains and the backline are hearing them arrive at about the same time, not so time smeared.

Very good then...I stand corrected.

 

[esoxhntr]

This may sound a bit naive - but why would you want to reproduce the sound of coupling anyway? First off it's a practical impossibility - consider the result of trying to live mic a bass cab onstage or in a room from 20 feet away. Talk about signal degradation... Secondly, yes we like the cabinet coupling for the presence and weight it gives us as a stage monitor, but a medium to large PA will have it's own coupling properties that are best not complicated by trying to reproduce individual cabinet coupling, as opposed to plain acoustic tone from the instrument/amp/cab combo. With a small PA, it doesn't have the size to couple, so you're really depending on a judicious combination of the room, the bass amp/cab, and a little bit of extra presence of bass in the PA for clarity, yes?

Or am I missing something?

 

[fokof]

Or am I missing something?

The context ?

Read answer #95 and before.....


I know it's impossible to reproduce , that' was the point

 

[JimmyM]

Whatever. Who cares if it's impossible to reproduce if the end result still sounds like your cab in the PA?

 

[esoxhntr]

And nobody talked about the coupling effect in a 8/10 that will not be capture by a mike it front of a single 10".....

Okay, sounds like you think this is an issue.

One easy solution would be to put the mike at 10-20 feet in front of the amp.

Yes easy, but impractical - unless you were kidding; in which case good one.

All those years carrying 8/10 for nothing when I could have done it with only one 10".......

A sarcastic reply, but still leads one to believe there is an issue...

I know it's impossible to reproduce , that' was the point

It's impossible so there is no issue?

Look dude, I read all the posts; I get the phasing thing, I get the DI/Mic crossover at 300Hz thing (quite clever - never heard of it before), I don't understand why worry about coupling. Either you're using small PA and the cab is still responsible for coupling, or you're using a bigger rig which couples with the room in which case the stage mix and the FOH mix are two different issues; the bass rig couples for the stage and the sound rig couples for the FOH.

So, I'm still trying to learn, but am still a litle confused on the issue - either you and I are talking apples and oranges, or you were kidding about coupling in the first place.

Or I'm dumber than dirt. And I'm not ruling that one out, not by a long shot.

 

[JackANSI]

Those arguing with JimmyM still seem to be failing to realize WHY he mic's and how it DOES WORK for him. He is going for a very specific tone. The easiest way to get that tone with accuracy is a mic on a cab.

Personally I don't feel its going to work for a majority of bassists, especially those with horns in their cabs. I think those people would be better served to start with a DI and maybe a mic combo.