Mic'd Amps and PAs

[Tab]

A question for the sound engineers really.

If you're micing up an amp to go through the main PA, what EQ settings would you use on the PA desk. Would everything be at zero, except for the volume, of course, or would one choose a neutral range for bass middle and treble? How much of the amp's tone, if any, is lost through the PA?

[dave robinson]

Tab, the microphone choice is important (I use a Shure SM57 for stage work) I always knock off the high treble as well as the bass when I mike the lead guitar, gently boosting the mid until I hear the same tone through the PA speakers that I hear from the amp. You don't want the high and low frequencies amplified if you require an early Hank tone, as it's mainly in the middle of the spectrum. PA systems vary in tonal response, so there isn't a set of parameters that I could advise across the board, but doing as I described in the first sentence is a stating point. On the rhythm guitar I would leave the treble and bass flat to start with and drop a little of the mid out to obtain a sweeter tone. Again this is only a crude starting point and you need to listen and compare what is coming through the front of house with the guitar amp.
I know it sounds a bit long winded but it is very easy to make a complete mess of the sound and there's no short, easy answer. It would actually be easier to show you if only you were closer to us geographically

[Tab]

Thanks Dave,

In the past, I've always worked with a band member who was also a decent sound man so I've never had to worry much about front of house.

Kind regards

[RogerCook]

In theory, at least a PA amp should be able to faithfully reproduce whatever sound is fed into it without adding or subtracting anything. In practice, however, the other links in the signal chain, notably mics and speakers, will introduce their own colouration to the sound. The Shure SM57 is probably the usual mic of choice for guitar cabs but I believe it was designed originally as a vocal mic . If you look at the response curves it shows a rising response around 6KHz so if you truly want to reproduce the sound of a guitar amp you would need to eq this frequency range flat. Speakers will definitely add their own colouration to the sound and again some judicious use of eq will be needed to deal with that. Mic placement also has an affect and the sound will vary as the mic is moved from the centre of the cone towards the edge. Mic'ing towards the edge is generally accepted as being the right place for a guitar amp cab.

As Dave says, no short answer and I think you need to let your ears be the judge of what sounds right

Roger

[Admin]

YHPM

Bob.

[dave robinson]

You're right Roger, I forgot to mention the microphone placement which is really important - it's like a massive tone control and make big differences as you move it across the front of the speaker. I recommend that you do this and listen to the difference to appreciate the different tones that are apparent.
I mentioned the SM57 as it is the best out of what we have to choose from - our SM58s and the Beyers' seems to add more colour to the sound than the SM57 and I won't use the AKG and Oktava microphones on stage in front of an amp for fear of someone kicking them over as they are fragile and expensive - we use those on the kit though.

[cockroach]

How did the Shads, and everybody else, ever cope, or get a decent live sound years ago?

Three small amps , a drum kit, and whatever house PA and microphones were there...even less for Elvis- one acoustic guitar with no pickup, one electric guitar, one small amp, drum kit, a stand up bass and one mic!