#1
Hello everyone,

I'm a noob at this so apologies in advance for a stupid question, but...

When playing live, what difference does the amp wattage make, if the amp (combo) is mic'ed anyway? Am I missing something? Why can't one theoretically mic a Roland Micro Cube then? Why do people mostly play live with powerful amps? For example, would a mic'ed Vox AC15 be playable live?

And is it always possible to mic a combo or does it vary from venue to venue? If I bring my own mic, will the sound guy accommodate?

I'm just thinking of getting a nice combo to play at home on loooow levels but to also be able to bring it with me for gigs. Again, if I mic it, I can theoretically play Glastonbury, can't I? The mic'ed sound goes to the PA and voila. So why would one need a 50 or 100 watt amp, if everything is miced? Same question goes for amp + cabinet, when the cab is mic'ed.

Could someone please explain
for rent
#2
Why can't one theoretically mic a Roland Micro Cube then?


You could just mic a Roland cube if you wanted to. However, you need to hear yourself while you play so it has to be powerfull enough for that. If you play outside, it's a little harder to hear yourself. Also, if you play in a band, the whole band needs to hear you while hearing themselves, wich often brings levels higher.

For example, would a mic'ed Vox AC15 be playable live?


This amp is playable live. The mic is for the P.A.. The amp is there so you can hear yourself.

And is it always possible to mic a combo or does it vary from venue to venue? If I bring my own mic, will the sound guy accommodate?


I never played a venue where is wasnt possible to mic, unless you are playing outside a cafe or somewhere like that where no P.A. has been set. They usually have all the mics necessary there, but if you like your mic better, bring it. I don't see why the tech would have a problem with that unless he can't manage your mic (somehow)...

I'm just thinking of getting a nice combo to play at home on loooow levels but to also be able to bring it with me for gigs. Again, if I mic it, I can theoretically play Glastonbury, can't I?


Yes you could play any venue, as long as you hear yourself, with a mic'ed amp.

So why would one need a 50 or 100 watt amp, if everything is miced?


It's not just a matter of loud. 50W dosent necessarly mean louder than 100W. You got to consider headroom and how much you need to crank the amp.I think most of the people that own these amps just like the way they are made and react and sound. I have a 40W combo and I regularly gig.
Last edited by Taz9 at Jul 19, 2014,
#4
Quote by Gakusey


When playing live, what difference does the amp wattage make, if the amp (combo) is mic'ed anyway?


The amp wattage doesn't mean much if you're going to be miked *and* if they're going to give you a wedge monitor or something similar to let you hear what you sound like, either by yourself or with the rest of the band. Clapton had his stuff under the stage at one concert, but there was a sound guy there to make sure that everything was set where it was supposed to be.


Quote by Gakusey
And is it always possible to mic a combo or does it vary from venue to venue? If I bring my own mic, will the sound guy accommodate?


It's not always possible to mike a combo. There are still a lot of gigs that have no PA at all (you have to bring your own) or where the PA is only for vocals, and where your amplifier will have to carry its own weight against an aggressive drummer, etc.

I have a couple of 5W amps, but they mostly stay at home. If I'm going to take an amp, it's usually something 50-100W, though I think 30W (tube) would be fine. I have 2x12 and 1x12 combos that can hold there own in these instances. I really don't find the 15W able to do that, though they're fine if you're miking at venues that support that.
#5
Quote by dspellman
The amp wattage doesn't mean much if you're going to be miked *and* if they're going to give you a wedge monitor or something similar to let you hear what you sound like, either by yourself or with the rest of the band. Clapton had his stuff under the stage at one concert, but there was a sound guy there to make sure that everything was set where it was supposed to be.


It's not always possible to mike a combo. There are still a lot of gigs that have no PA at all (you have to bring your own) or where the PA is only for vocals, and where your amplifier will have to carry its own weight against an aggressive drummer, etc.

I have a couple of 5W amps, but they mostly stay at home. If I'm going to take an amp, it's usually something 50-100W, though I think 30W (tube) would be fine. I have 2x12 and 1x12 combos that can hold there own in these instances. I really don't find the 15W able to do that, though they're fine if you're miking at venues that support that.


Ok, cheers for that as well! Thanks guys
for rent
#6
Quote by Gakusey
When playing live, what difference does the amp wattage make, if the amp (combo) is mic'ed anyway?


strictly speaking? there is a mathematical formula:

dBm = (10*LOG10(watt))

that provides how many dB an amplifier provides. mind you the sensitivity of the speaker does come into play. so if you want the output of an amplifier you'd have to provide the power output of the amp and speaker sensitivity.

so lets say you have a 100 watt rated amp, and lets assume you are using it's full output. then we'll say the speaker is 100 dB output.

X(ratio louder) = 2^log10(P2/P1)
dB louder = 10*(LOG10(P2/P1))

assuming P1 is a 1 watt amp then a 100 watt amp would 4 times louder (or 20 dB louder) than a 1 watt amp. then you'd consider speaker sensitivity of 100 dB (at one meter at 1 dB) and you'd get:

speaker sensitivity in dB + output of amplifier in dB = 100 + 20 = 120 dB

if you'd want to compare something like a 50 watt amp to a 100 watt amp (assuming nominally rated output) then you'd use the previous formula:

X(ratio louder) = 2^log10(P2/P1)

and get something like the 100 watt amp i 1.2 times louder than the 50 watt amp.

that might be a bit to quantitative for you, but the answer comes down to the fact that the volume output doesn't mean much. the more important stuff is how the tubes respond at such volume levels.

Quote by Gakusey
Am I missing something?




Quote by Gakusey
Why can't one theoretically mic a Roland Micro Cube then?




if someone has a PA (complete with monitoring), then they easily could. in fact, if they have a PA they could bypass an amp altogether and play directly through a setup with no power amp or speaker.


Quote by Gakusey
Why do people mostly play live with powerful amps?


in a standard since, guitarists use guitar amps. they have a particular tones they have come to prefer from these guitar amps. but if you think the volume of the guitar is directly from the guitar amp then you are mistaken. even coliseum-looking guitar rigs are generally empty-cabinet eye candy. the sound guy that controls the PA generally controls the volume of the guitar in the mix.

mind you, if you are garage band with no sound PA or sound guy, then your guitar's volume does come from the amp. in that case you need an amp that is loud enough to be heard in the mix. but as you can see above 'watts' have little to do with your overall volume, but they do have much to do with how your guitar sounds at higher volumes.

Quote by Gakusey
For example, would a mic'ed Vox AC15 be playable live?

certainly, providing the PA is adequate

Quote by Gakusey
And is it always possible to mic a combo or does it vary from venue to venue?


it depends on your PA and your sound guy. many bands (even cover bands) will provide their own PA and sound guy so they don't have to rely on a venue.

so it does depend on what the venue provides, but it also depends on what your own band can provide

Quote by Gakusey
If I bring my own mic, will the sound guy accommodate?


see above

Quote by Gakusey
I'm just thinking of getting a nice combo to play at home on loooow levels but to also be able to bring it with me for gigs. Again, if I mic it, I can theoretically play Glastonbury, can't I?


sure, many pro acts still play with tweed deluxe style amps which couldn't be heard in a mix without a PA (provided you're playing an arena show)

Quote by Gakusey
The mic'ed sound goes to the PA and voila. So why would one need a 50 or 100 watt amp, if everything is miced? Same question goes for amp + cabinet, when the cab is mic'ed.


cuz those amps provide a different response. the type of circuit (for example class A or class A/B) and components (for example power tubes and output transformer) depend on how the amp sounds.

my supros use pentode preamps, class A power stages and have far less headroom and a grittier sound than say my class A/B, high gain CEC brigand.

i would use either amp depending on the tone i want, not how much volume output it can provide.

Quote by Gakusey
Could someone please explain


maybe
punk isn't dead, it's always smelled that way.

"A perfection of means, and confusion of aims, seems to be our main problem."
-ae
Last edited by gumbilicious at Jul 19, 2014,
#7
The short answer is - autonomy. If your amp is big enough to hear it without having to put some through the wedges, YOU have the control over your monitoring, not the sound guy; who could be a douche. Things run smoother if all he has to worry about is FoH.
Also, I don't like anything through the wedges but the vocals, especially if I am singing - and the singer (if it's not you) will feel the same way about it.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#8
Thank you Cleared that up for me So basically, using the above Vox example, the AC30 theoretically has a "richer" sound than the AC15? Not in terms of loudness, but headroom and how much you can push it?

P.S. I was asking this partially because I *hate* going direct. I want the tone from the amp, so my Micro Cube example was just an extreme to illustrate a point. I was basically asking that, if I liked my 15 watt combo tone very much, could I use it to play live anywhere (possibly) if it's mic'ed.
for rent
Last edited by Gakusey at Jul 19, 2014,
#9
Not richer, and those two amps do have their own unique sound, one isn't just a louder version of t'other. As far as that goes it's all about cleans. If you don't need clean cleans then the AC15 may be the better amp for you. If you always want some grit in your sound the AC15 is plenty loud enough to hear yourself over the drummer and in that instance the AC15 would likely be the one you thought sounded "richer" because you are getting some power tube distortion.
If you want pristine cleans against a drummer, then the AC30 is the way to go - unless you specifically want that AC15 sound.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#10
Quote by Cathbard
Not richer, and those two amps do have their own unique sound, one isn't just a louder version of t'other. As far as that goes it's all about cleans. If you don't need clean cleans then the AC15 may be the better amp for you. If you always want some grit in your sound the AC15 is plenty loud enough to hear yourself over the drummer and in that instance the AC15 would likely be the one you thought sounded "richer" because you are getting some power tube distortion.
If you want pristine cleans against a drummer, then the AC30 is the way to go - unless you specifically want that AC15 sound.


In this respect, may I ask if there's a way to "de-grit" the AC15, i.e. to have it loud but clean? Maybe a pedal? Maybe have the amp at a moderate volume and use some good clean boost? Just curious
for rent
#11
No. To do that you have to mike it up.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#12
One sort of related question...when a band is playing a stadium, and they have ear plugs which I assume are monitors...why do they also have wedges? And could they possibly hear anything from the wedges with the crowd and volume needed for a stadium?
#13
Some people don't like ear plugs.
They use good wedges. It isn't as loud on stage as it is out front you know? The PA bins are pointing away from you.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#15
One sort of related question...when a band is playing a stadium, and they have ear plugs which I assume are monitors...why do they also have wedges?


They can mix things however they like. Singer in-ear, the rest of the band from wedges for instance.
#16
Quote by Skeld1
I figured it wasn't quite as loud on stage, but still...
Not even close.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#17
Quote by Cathbard
Not even close.



This.

If there's enough room for the sound to go you can talk to each other behind the pa speakers. Soundwaves are waves and as such very directional. From a natural soundsource, the waves vibrate all around the object, but speakers project.

A lot of perceived volume also comes from the ratio between room size/shape and output volume due to reflections.

Outside venues can not make use of this and thus need far more power to get the same perceived loudness. The advantage is u can turn it up very loud and if engineered and mixed wel on stage create a very exciting dynamic range.


As for the main question. Yes you can mic anything.

Remember a (good) mic picks up the dynamics from the sound source and a lot of amps available that can get a more rich dynamic range seem to be medium to high wattage tube amps.

A good example would be a snare drum. When you hit it softly the tail end of the sound peaks and resonates out at the lower frequencies. Hitting it hard results in peaks and tail resonance at higher mid frequencies. Louder and popularly tube amps seem to produce a nicer and better projected "variation" throughout the frequency spectrum through the player's technique as opposed to a lot of smaller and/or non tube amps.

Yes u get excited just by feeling the energy of just louder frequencies, but the original sound source is responsible for the dynamics of the individual sound, not the PA, unless rick rubin has a night out and goes ham on the desk compression if available.

Tldr;

Just think of it as a picture, if it's far too dark, u can brighten it digitally, but then u get brighter darks all around, not a brighter more rich or more colourfull source.

Making shit louder results in loud shit.

The "Re-incarnation of Plato" Award 2009
(most intelligent)
The "Good Samaritan" Award 2009 (most helpful)

[font="Palatino Linotype
Who's Andy Timmons??
Last edited by xxdarrenxx at Jul 21, 2014,
#18
Quote by xxdarrenxx
Making shit louder results in loud shit.


The same blunt logic ties into recording. You can record with any piece of gear but the end result is still going to heavily rely on the quality of that raw track. There's all sorts of studio wizardry to enhance anything, but polishing is turd is polishing a turd at the end of the day.