Amplifiers for vocals..........

We just keep a mic in front of the bass.....another in front of the snare, hi hat.......another on the left side for the cymbals and tom....................My drummer actually cut his bass pad/skin from the front so that the mic could poke into the drum.............PS the effect wasnt too great........he had to change the pad..............

 

Oh yeah, those el-cheapo mixers will do very nice.
The main thing you require is a volume balance. EQ etc leave it for final PA system.

 

^^thanks for the info mate........

 

@alpha: wt will b minimum requirement if u also need to eq a bit... Trying to leave nothing fr the sound guy wen he is good fr nothing...
.
@angel of sin: n wt mics do u use?

 

^ I have already posted this before man.......he uses my philips mic which i got for 1.6 k.....coz he shure mic cracked open.........lol.......(irony is that Shure claims they make the world's toughest mics..........

 

I forgot about the impedance bridging. I read my Laney's manual and it's rated at 1Mohm. Still, for this mic that would matter only in line level input without a preamp. So what is the difference in the input structure that makes the guitar amplifier inefficient? Could you point me towards some information?

BTW my Zoom's manual says the output is +3dBm (at 10k ohm load impedance or higher). So it's basically a line level output right? Better than some of the Korg models that have instrument level outputs I guess. But +3dB is neither semi pro line level nor pro line level. What gives?

And is this set up (Zoom -> amp) high Z - high Z or low Z - high Z? I'm wondering if it's relative because so far I seem to have got the idea that <1k ohm = low Z.

EDIT: Seems the guidelines are 600-1000 = low Z, 1000-10000 = medium Z and >10000 = high Z. Ignore the question.

 

are you sure that we do not use instruments with almost the same impedance????? coz from what i h've heard high Z- lowZ and Low Z to high wont give that great an output.................they have to be at the same level.........i may be wrong though......

 

Low Z - High Z is low distortion.
High Z - Low Z will probably add a lot of noise.
Low Z active pickups can still be plugged into your high Z amp input with no loss of volume.

When the load impedance is much higher than the source impedance we have maximum voltage transfer rather than power transfer which is good for audio systems because we'd rather be able to have a reign over the output than be able to blast it. The high voltage at input (due to high input impedance) allows greater bandwidth to be transferred and also somewhat compensates for variable cable lengths. Usually the much higher means 10x as high.

Hence mixers usually have a mic level input at 1500 ohms, line level at 10k ohms and guitar amplifiers have an input (instrument level) at 1M ohm.

Impedance matching (load impedance = source impedance) is something you need to consider when connecting the speakers to an amplifier. Because too low and impedance will overload your amplifier. Hence you must make sure that you connect the speakers correctly.

If your amp has a speaker out rated at 8 ohms (which is a very big misnomer as power amplifier output is always < .5 ohm. Read about damping factor DF) then the impedance must be no less than 8 ohms. So you can connect 1 speaker rated at 8 ohms, or 1 speaker rated at 16 ohms. You can connect 2 speakers rated at 16 ohms in parallel but NOT 2 8 ohm speakers in parallel.

 

EDIT: Double post, sorry.

 

by damping factor do you mean......Frequency Dependent Damping????? just asking ....i have no idea what either is....please shed some light on both..............

 

The damping factor allows control over the motion of the speaker cone, providing a more "accurate" sound.

DF = Z load/Z source

A guitar amplifier's poweramp stage has a source impedance of < .5 ohm. The loudspeaker on the other hand typically has a load impedance of 4-8 ohms. So now based on this you can calculate the damping factor (or, based on the Z load and DF, calculate the Z source). Usually a high damping factor is said to give a more controlled sound. But again, the damping factor changes with frequency because the impedance changes with frequency.

Frequency dependent damping in a oscillating motion is not the same thing AFAIK.

BTW I just found out that instrument level voltages are roughly similar to line level but the impedance is higher.

 

woah that means that we by mistake buy the right stuff for ourselves???????

 

No we don't. I'm only talking about the technical specifications.

@alpha1: How are you going to convince the sound man to leave the volume balance alone? It doesn't make sense to put an extra mixer in just for that.

 

Thats because there will be only one output from your personal mixer.
Individual instruments are "mixed" by you only.
The max this external sound guy can do is to change the overall volume of this mix of perhaps EQ it + add/subtract some effects (like reverb etc)

 

So u cant eq the individual instruments... Coz yrour mixer wont do it efficiently... N the soundguy gets only the mix...
Does it nt restrict ur sound?
Doesnt seem to b a gud idea...

 

That's what I'm saying. You need to monitor your sound in a live setup, and so if you want to use your own then you'll want a mixer with a good number of pre-fade aux outs. I can't imagine choosing to balance volume for the mix over being able to monitor my sound.

And if he adds reverb he adds it to the entire mix. Ugh.

 

Strictly speaking, you wouldn't bother about individual instrument EQ in the mixer.
That should be taken care by the instrument player and his equipment.

Now when everything comes to a final mix via the PA system - the sound guy listens and changes the EQ of the entire mix - because the PA system is gonna play the entire mix, and not individual instruments.

And a tad reverb is added by many soundguys just to give a hint of large soundstage.
Its not like the reverb you use on the guitar effects to sound like a surf genre guitar.

 

I agree to all the quotes by alpha1 &....

I agree to all the quotes by alpha1 & would add further that....

If u have a bit of cash thn buy a Mixer, pair of 15" Active Speakers and 1 good Mic preferably SM58.

I recommend a Mackie CFX Mk II 8 Channel Mixer, delivers tight, KADAK, crisp & clear mix. Has on-board Effects. Try tweak'in the EQ's and you will find substance in the Mix out. Moreover you will learn abt your personal EQ levels and picture of actual output on the PA. So u can command on the Sound Engg.

And i recommend a dB Technologies 15" Active speakers. They produce decent low frequencies along with Mid's & Hi's. So your overall Vocal problem is solved. U can also carry your active monitors on your gig and use them as monitors

 

@alpha1: True but I still want to be able to monitor as per each band member's requirement, so it's either a high end mixer with multiple aux sends or the sound man's mixer.

 

1. Nice, specific and detailed advice but...
2. ...I suspect you're a shill o.o'
3. Sorry if you're not! =P

https://en.wikipedia.org/wiki/Shill