I'm a plug in and play kind of guy. I've had a few people tell me I should get a pre-amp and decent acoustic mic. So, I went to Sam Ash where the guy tried to sell me a $1500 mic and $600 pre-amp. Which I can't afford.
So, I asked [mod edit] my sound engineer who is a music guru, and has recorded numerous hit makers from the 60s and 70s [mod edit] if he could recommend a good pre-amp and mic for acoustic that wouldn't be outrageously expensive.
He told me about a Tube MP preamp that goes for about $50 and a new mic that was sent to him to test and check out, a Karma Icon mic for $100. I'm still waiting for the mic, but his advice is always solid.
He also sent along the following instructions. Just because I have the equipment doesn't mean I can really use it.
If you're an experienced engineer this isn't new to you. But, for those that might be starting out, it's pretty useful (at least I think so).
Here it is:
In recording any sound source, you want to input the mic pre with as much signal (volume) as possible before overload. This is because you then have to output the pre less, yielding less noise. It's a "signal-to-noise" issue. The more in, the less out necessary. Remember this principle always.
All electronic audio devices generate noise (no matter how little). So the less output you need to use, the less noise you'll have.
More input = less output needed = less noise = cleaner signal.
Turn a guitar amp's output volume up and you get hiss and maybe some hum. The more you turn it up, the more hiss and hum you get. You already know this. But if the guitar is feeding into the amp at a high volume (volume knob on guitar up high), the amp (both its input and output) can be set lower, and therefor less hiss and hum. This gives you a high "signal-to-noise" ratio; a clean sound. If you want some guitar distortion and noise, lessen the "signal-to-noise" ratio by overloading the amp's input and setting the output where you want it.
Source distortion overload comes from too much INPUT, not output. (you can also overload your mixing board or recording device, of course, but I'm talking about SOURCE DISTORTION before the mixing board or recording device stage).
With mic pres, you can do the same thing, 'tho it's rarely desirable. That is, if you raise the input you'll get an edgy (distorted) sound at the output, no matter where the pre's output volume is set. In this scenario, the distortion and noise is happening at the input (because you're feeding it a lot of signal; more than the pre's input likes to see), so the distortion and noise appears at the output stage. The pre's output knob simply lets you select how much of the distortion and noise you want to use. Do you see that?
Now, to the TUBE MP's settings procedure:
1.There is no on/off button, so insert the 9volt connector into the pre, but do not plug the wall wart into the wall yet.
2.Turn the INPUT knob fully counter-clockwise.
3.Keep the +20 db GAIN switch up.
4.Keep the P-POWER 48V switch up.
5.Keep the PHASE REVERSE switch up.
6.Turn the OUTPUT knob fully counter-clockwise.
7.Insert your output wire (XLR or 1/4") from the pre to your mixing board or recording device.
8.Insert the mic or instrument into the input jack (only one input; don't use mic and instrument together).
9.Plug the wall wart in. The pre is now on. (I like to warm the tube for a half hour before use, but it's not necessary).
10.For a condenser mic, press down on the P-PWR 48V switch; phantom power is now on. Dynamic/non-condeser mics don't need phantom power, so keep the P-POWER 48V switch up for those mics.
11.With your sound source sounding at the volume you want (for example, the singer singing at the volume s/he will be singing at for the recording), slowly rotate the INPUT knob clockwise until the POWER/CLIP light indicator starts to register in green (not red). The peak volumes should keep the light blinking a lot, but never go into the red, even 'tho an occasional red light will be ok. A rehearsal of the song will usually show you where your level peaks are, so set the INPUT knob for the loudest peak.
12.At this point, your mic pre is operating at maximum efficiency. That is, the signal-to-noise ratio is optimal and the mic pre is getting just the right amount of signal (it's not distorting the pre's input stage).
Now, what to do with that optimal signal.
13.Turn the OUTPUT knob clockwise until your input device (mixing board, recorder, or whatever) is getting the correct amount of signal, using its level indicators as you normally do.
14.For an instrument input (1/4" input, not XLR input), keep the P-PWR 48V switch up. You don't need phantom power for this. Use the same procedure as above.
15.You should need the +20 db GAIN switch only for ribbon mics, which have low output. If you find yourself needing the +20 db GAIN switch because you can't seem to get enough output from your sound source, something is probably wrong. Sing louder or closer or raise the output volume of the source instrument. Using the +20 db GAIN switch on anything but a ribbon mic will probably hurt your signal-to-noise ratio. I've never had to use it.
16.Generally, you won't have to use the PHASE REVERSE switch. This flips the polarity of the signal, a subject for another time, I think.
17.Always use the mic pre in an open space, where there is air to keep the tube relatively cool.
I hope this long-winded set of instructions helps you. It presumes, of course, that your pre and mine is the same. I believe it is and that no changes have been made to the TUBE MP mic pre since I bought mine some years ago. But no matter what pre you have, the underlying principles I've outlined for you are still viable.
So, I asked [mod edit] my sound engineer who is a music guru, and has recorded numerous hit makers from the 60s and 70s [mod edit] if he could recommend a good pre-amp and mic for acoustic that wouldn't be outrageously expensive.
He told me about a Tube MP preamp that goes for about $50 and a new mic that was sent to him to test and check out, a Karma Icon mic for $100. I'm still waiting for the mic, but his advice is always solid.
He also sent along the following instructions. Just because I have the equipment doesn't mean I can really use it.
If you're an experienced engineer this isn't new to you. But, for those that might be starting out, it's pretty useful (at least I think so).
Here it is:
In recording any sound source, you want to input the mic pre with as much signal (volume) as possible before overload. This is because you then have to output the pre less, yielding less noise. It's a "signal-to-noise" issue. The more in, the less out necessary. Remember this principle always.
All electronic audio devices generate noise (no matter how little). So the less output you need to use, the less noise you'll have.
More input = less output needed = less noise = cleaner signal.
Turn a guitar amp's output volume up and you get hiss and maybe some hum. The more you turn it up, the more hiss and hum you get. You already know this. But if the guitar is feeding into the amp at a high volume (volume knob on guitar up high), the amp (both its input and output) can be set lower, and therefor less hiss and hum. This gives you a high "signal-to-noise" ratio; a clean sound. If you want some guitar distortion and noise, lessen the "signal-to-noise" ratio by overloading the amp's input and setting the output where you want it.
Source distortion overload comes from too much INPUT, not output. (you can also overload your mixing board or recording device, of course, but I'm talking about SOURCE DISTORTION before the mixing board or recording device stage).
With mic pres, you can do the same thing, 'tho it's rarely desirable. That is, if you raise the input you'll get an edgy (distorted) sound at the output, no matter where the pre's output volume is set. In this scenario, the distortion and noise is happening at the input (because you're feeding it a lot of signal; more than the pre's input likes to see), so the distortion and noise appears at the output stage. The pre's output knob simply lets you select how much of the distortion and noise you want to use. Do you see that?
Now, to the TUBE MP's settings procedure:
1.There is no on/off button, so insert the 9volt connector into the pre, but do not plug the wall wart into the wall yet.
2.Turn the INPUT knob fully counter-clockwise.
3.Keep the +20 db GAIN switch up.
4.Keep the P-POWER 48V switch up.
5.Keep the PHASE REVERSE switch up.
6.Turn the OUTPUT knob fully counter-clockwise.
7.Insert your output wire (XLR or 1/4") from the pre to your mixing board or recording device.
8.Insert the mic or instrument into the input jack (only one input; don't use mic and instrument together).
9.Plug the wall wart in. The pre is now on. (I like to warm the tube for a half hour before use, but it's not necessary).
10.For a condenser mic, press down on the P-PWR 48V switch; phantom power is now on. Dynamic/non-condeser mics don't need phantom power, so keep the P-POWER 48V switch up for those mics.
11.With your sound source sounding at the volume you want (for example, the singer singing at the volume s/he will be singing at for the recording), slowly rotate the INPUT knob clockwise until the POWER/CLIP light indicator starts to register in green (not red). The peak volumes should keep the light blinking a lot, but never go into the red, even 'tho an occasional red light will be ok. A rehearsal of the song will usually show you where your level peaks are, so set the INPUT knob for the loudest peak.
12.At this point, your mic pre is operating at maximum efficiency. That is, the signal-to-noise ratio is optimal and the mic pre is getting just the right amount of signal (it's not distorting the pre's input stage).
Now, what to do with that optimal signal.
13.Turn the OUTPUT knob clockwise until your input device (mixing board, recorder, or whatever) is getting the correct amount of signal, using its level indicators as you normally do.
14.For an instrument input (1/4" input, not XLR input), keep the P-PWR 48V switch up. You don't need phantom power for this. Use the same procedure as above.
15.You should need the +20 db GAIN switch only for ribbon mics, which have low output. If you find yourself needing the +20 db GAIN switch because you can't seem to get enough output from your sound source, something is probably wrong. Sing louder or closer or raise the output volume of the source instrument. Using the +20 db GAIN switch on anything but a ribbon mic will probably hurt your signal-to-noise ratio. I've never had to use it.
16.Generally, you won't have to use the PHASE REVERSE switch. This flips the polarity of the signal, a subject for another time, I think.
17.Always use the mic pre in an open space, where there is air to keep the tube relatively cool.
I hope this long-winded set of instructions helps you. It presumes, of course, that your pre and mine is the same. I believe it is and that no changes have been made to the TUBE MP mic pre since I bought mine some years ago. But no matter what pre you have, the underlying principles I've outlined for you are still viable.
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