38

In many live music contexts, musicians have the problem of hearing themselves clearly. Typically when playing loud, musicians are positioned behind the main speakers (heard by the audience) to avoid feedback, and for the safety of their own ears. In that basic scenario, musicians only hear: the quiet sound coming from their acoustic instruments or voices ...


24

A balanced setup prevents electro-magnetic interference from corrupting an audio signal, such as one going between a microphone and a preamp, for example. Cables themselves are not balanced, but an audio signal carried by a cable might be balanced. Cables which carry such signals normally have three conductors. Microphone cables are a typical example. The ...


23

As others have noted, the properties of the signal from the microphone and from the piezo pickup will be different. The microphone picks up the same kind of air vibrations your ear does. The piezo pickup picks up the vibration of the saddle. The pickup has the advantage of being less susceptible to (but not immune to) feedback, and it moves with the guitar. ...


22

In these pictures it's likely that one mic is for the PA and the other mic is for recording. Either they didn't have mic splitters or they didn't trust them! This was a very common way of doing things in the 70s. The Grateful Dead are known to use two mics as a noise cancelling technique. The output of the two mics is combined with equal levels but opposite ...


20

This is partly a myth and partly due to the physical size of the bass. Some people (even professional musicians) believe that low frequency sound waves "need room to develop". That's completely false. One thing that can happen with low frequency waves is they are more likely to form standing wave patterns inside smaller rooms. Those patterns will create ...


19

I'm going to offer a non-technological suggestion. As several answers have already observed, you're fighting some impossibilities (not the least of which is "I have been assigned to improve the audio quality in a school auditorium," presumably without any significant budget, just the expectation that you can create acoustics by tweaking a few pots)....


17

There are three things I'd recommend in terms of PA-settings that do usually make a significant improvement on intelligibility in excessively reverberant rooms: Cut the bass. Like, properly. Many consoles have 80 Hz low-cut filters on each channel, definitely use those, but in addition don't hesitate to pull down a 100-150 Hz band as far as it goes, perhaps ...


16

It's not a microphone; it's directional antenna for wireless microphone systems. See http://www.shure.com/americas/products/accessories/wireless-systems/wireless-systems-antennas for details.


13

The most important difference between passive and active DIs is that the latter have a much higher input impedance: usually something like 200 kΩ, whereas a passive DI "inherits" the low impedance of the mic input you're feeding (around 2kΩ), or transforms it up a bit to something in the 20 kΩ range. That makes hardly a difference for instruments with low ...


12

Amp miking is basically a ridiculous thing to do: a speaker is, in principle, a device to make an electric signal audible. A microphone is a device to do the opposite. Neither does its job perfectly, in particular it's very hard to design a speaker with truely even frequency response. A purely electrical transmission is obviously much better, cleaner, from a ...


11

A DI ("Direct Input") box converts a signal on an unbalanced lead into a signal on a balanced lead (that is, usually a lead with XLR connectors). The advantage of a balanced lead, of course, is that you can run it for long distances without hearing interference. With a passive DI, the signal on the XLR lead is at the same level as the input signal. So, if ...


10

The sound from a microphone inside the guitar (or piezo pickups as in the case with Clapton) is different from the sound outside of the guitar. The signal from internal microphones or pickups will be more consistent, since it is not affected by movements of the guitar. Likely the signals are mixed to get the best of both worlds.


10

As a sound technician for my church, one of the most important roles is making sure the musicians can hear themselves. This is done by controlling the levels in the monitors. Often, these sit on the stage and are called "Floor Monitors". These sit between the musicians and the crowed, and are pointed back at the performer.


10

Feedback, bleed, clarity in the mix. All these apply to both miking an amp and miking the guitar directly without using an amp. These apply to using microphones in general, in any instrument, with or without amps involved. It depends on the venue (dimensions, materials, shape), the equipment (mics, amps, PA, monitors), and the performance (# of instruments, ...


10

A DI box breaks the galvanic connection. It's most important use is breaking ground loops, and also for changing unbalanced signals to balanced (the latter transfering better over long connections). If your effect boxes are running on battery and are not mounted on metal and go to an instrument amp (rather than a mixer) next, the DI box will not do much ...


9

I can't recall ever seeing it, but do people use pop filters in a live/concert/performance setting? I see where you are coming from. We see all these vocalists almost eating the mic and screaming and doing things that should flood the sound with loud plosives, but they don't. And they are not using pop filters... Or are they? In fact, they are using pop ...


9

I play both cello and E-bass live with rock bands. For cello (this would probably extend quite well to most other acoustic instruments) in-ears are nothing short of a blessing. With conventional monitoring, feedback is always a very serious threat. With in-ear it's seldom an issue at all. I can always hear my own notes excellently, which makes intonation a ...


9

If the sound 'developing' includes adding some reverb, I can see what they're talking about. But this isn't unique to bass instruments. There's a rule-of-thumb in 'classical' recording that you shouldn't mic an instrument any closer than its length. 4½ft for a trumpet, 9ft for a trombone, 6ft for a string bass. Partly so as not to emphasise mechanical ...


8

The standard for big gigs is for the PA speakers to be in front of the performers, pointing at the audience. So as not to block the view, they're typically in front and to the side, or above the stage and pointing downward. The point of this is that the audience gets loud music, while the musicians are in a quieter area, where they can hear the music more ...


8

The demands on an amplifier/speaker combo designed to reproduce the sounds desired for bass guitar are different than for a regular guitar. To accurately and faithfully reproduce the low frequencies needed for bass guitar, the speaker surface must be able to move a greater distance and move more air. This greater movement demands more room in the cabinet ...


8

Firstly, does your USB keyboard have MIDI out (DIN) sockets as well... ...or is it USB only? If it is USB only, then it is possible to get a hardware converter (from USB to traditional 'DIN' MIDI) that should work as long as the USB Midi keyboard is 'class compliant'. an example is http://www.kentonuk.com/products/items/utilities/usb-host.shtml. Once you ...


8

If you're willing to do it DIY, single board computers like a Raspberry Pi have enough processing oomph to act as (simple) synthesizers. They come with a USB and sound ports, it's just a matter of piecing together the midi driver and a synthesis engine software. Some examples of Pi based synthesizers can be found here.


8

Mixing consoles don't have space to house top-notch (and expensive) discrete preamps. The Soundcraft preamps may be, well decent – that is, sufficient for any typical source: condenser mics and active DIs already pump the line with considerable levels, whereas dynamic mics and passive DIs are mostly used with instruments that are so loud that you don't need ...


8

The drummer usually has a click (and the track) in his (in-ear) monitor. The rest of the band can choose if they want the additional track in their monitors or not. As long as they can hear the drummer they'll be in sync with the track.


7

Adding to Meaningful Username's answer, the different sources (piezo pickup vs microphone) emphasise different parts of the guitar's sound. Not only is it used to help the sound be more consistent etc. but the different sounds themselves make for much more versatility when mixing. In general (this can vary wildly) a microphone will give a more "natural" ...


7

Another term for monitoring is 'foldback', which sums it up quite nicely. The sound is re-routed via speakers- on stage or in ear,in order to be useful to each muso. Care needs to be taken that the mix given to each individual is not tainted by any other sound source.Drums and bass, for example, need to hear each other far more than , say keys, so the ...


7

Led Zeppelin was impressive for many reasons, including the fact that they relied on musicianship and live performance to produce live arrangements of heavily produced and overdubbed songs that everyone knows. They did not use extra players, recorded tracks, or excessive harmonizers to do more than four players could do with their own four mouths, eight ...


7

The biggest advantage for line out is that you don't have to worry about feedback, and that you can model the tone without worrying about positioning, angles, mics, bleeding, etc; which is a disadvantage of the mic-amp combo, you need to worry about a lot of things to be able to do it correctly. If you love the sound that comes out of the speakers of the ...


7

I see in the comments that you are already familiar with the polar patterns. For the readers that don't know them, here they are: Polar pattern: A microphone's directionality or polar pattern indicates how sensitive it is to sounds arriving at different angles about its central axis. Simply put, from which directions the microphone is capturing sound. Here ...


7

In a lot of mixes, it's normal and even intentional for the acoustic guitar(s) to get hidden behind the electric guitars and other instruments during the loud parts. If you listen to the Led Zeppelin songs that have both acoustic and electric guitars, it can sound like the acoustic track is muted during the "loud" parts, but it's usually actually sitting ...


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