Another amp questions I should know...Gains!

To many ads? Support ODJT and see no ads!
LoudspeakerDJ

LoudspeakerDJ

New DJ
Nov 16, 2006
116
0
48
Special thanks to everyone who has helped me by answering by questions regarding amp ohms and the like, but here is my next question....

Where should the gains be set on my equipment?

With each channel on the mixer having gains, each amp channel having gains, and my eq having gains as well for each channel, I'm not sure what is best for my system. I have been running the gains on my mixer about even steven, maybe a small change on them, but adjusting the gains on the amps, so that the loudest out on the mixer is about the volume I want the venue to be at? Does this make sence? Currently, such as last night, my gains on the amps were at about 1/3 on. Is this what I should be doing?

Thanks again
 
Your gain on your amps should always be wide open.

Eq's generally have a +/- setting. They should be set at 0.

Your channel gain should be brought up to 0 db on your level meter.

The channel faders control your level in the mix.

Your Master Out is your main volume.
 
This is more of a unity gain issue. :)

Every professional processing component has gain adjustments. Not to be confused with level controls (channel sliders), gains should be set at unity for the best performance.

To start, set gains at center detent. Monitor your level LEDs or meters to ensure that you don't go out of the "yellow" or above desireable gain. Adjust so that signals are below the "red" for each component.

EQ settings should also be set to center detent at first. Tweak the EQ slightly to "ring" or reduce feedback from your mics. Otherwise, leave it alone.

Your power amps should be set to no attenuation (full) for maximum headroom. Output level is controlled at the mixer.
 
For Maximum headroom best experience is to set your mains & desired channel slider to Unity or 0db.

Start with your gains all the way to the left, then ask your vocalist to start talking "check check" monitor what is being outputted on the main mix vu meters, adjust your gain until the leds light at 0 db consistently... Doing so gives you the best amount of "play" and prevents your amp from being damaged.

Some high-end boards already have the VU meters on a per channel basis, remember these are pre-fader meters, and you can set those to 0db as well... Also another method includes using the Solo or PFL (Pre-Fader Listen) and checking the VU meters there as well.

Amps, leave them wide open, unless your using some type of crossfader on them, like a drive rack... If your bass or high is too much, use your amps versus using the drive rack, since it is far much easier to manage.

----
Let me know if you have any more questions about specifics on Live Sound, I started doing live sound before I became a DJ and I have learned best practices from some of the greatest sound engineers around.
 
Bounce said:
For Maximum headroom best experience is to set your mains & desired channel slider to Unity or 0db.

Start with your gains all the way to the left, then ask your vocalist to start talking "check check" monitor what is being outputted on the main mix vu meters, adjust your gain until the leds light at 0 db consistently... Doing so gives you the best amount of "play" and prevents your amp from being damaged.

Some high-end boards already have the VU meters on a per channel basis, remember these are pre-fader meters, and you can set those to 0db as well... Also another method includes using the Solo or PFL (Pre-Fader Listen) and checking the VU meters there as well.

Amps, leave them wide open, unless your using some type of crossfader on them, like a drive rack... If your bass or high is too much, use your amps versus using the drive rack, since it is far much easier to manage.

----
Let me know if you have any more questions about specifics on Live Sound, I started doing live sound before I became a DJ and I have learned best practices from some of the greatest sound engineers around.
Click to expand...

I'm surprised to hear the amps should be wide open. If this is the case, the main volume slider on my mixer at some events would be maybe at a 2 out of 10 being the highest. I will give it a try though next week.
 
LoudspeakerDJ said:
I'm surprised to hear the amps should be wide open. If this is the case, the main volume slider on my mixer at some events would be maybe at a 2 out of 10 being the highest. I will give it a try though next week.
Click to expand...
No surprise. This has been a recommended practice from the soundmen ever since I can remember.

Bear in mind that the master controls everything, mic inputs included. I don't recommend messing with the master once you've got your sound checks done. Bumping the master will bump the mic levels as well... and may raise a feedback issue. :)
 
Listen carefully to your system with the amp gains wide open. Any component noise and interconnect noise will have full amplification as well!
 
Right. And just how many people know and set up systems using proper sound techniques??
 
Bryan Durio said:
Listen carefully to your system with the amp gains wide open. Any component noise and interconnect noise will have full amplification as well!
Click to expand...

Hi brian, not to be kurt but what is the point? That is common sence. Are you suggesting NOT to have the gains turned all the way up?
 
LoudspeakerDJ said:
Hi brian, not to be kurt but what is the point? That is common sence. Are you suggesting NOT to have the gains turned all the way up?
Click to expand...

Loudspeaker - Fred and Bounce speak from experience. You can trust what they say. I have run live sound for bands, live theatre events,etc. from small and smoky bar rooms to 30,000 seat arenas. ALWAYS run your gain at full for maximum headroom. In your case, I would venture to say the largest attended event you would provide sound (right now) for would be a gym filled with 300+ high school kids.

If you run your amps with the gain at full, the signal that reaches those amps, once processed thru an E.Q. and active crossover, will most definitely be louder and cleaner than if you ran them at 12 o'clock with your mixer close to red-lining. When you red line the level on your mixer, you are already dis-coloring and distorting the sound before it even has a chance to be processed. True, when you run in this configuration, you will wind up running your master gain on your mixer output at maybe 2 or 3, but by doing this, you are giving your system a chance to breathe and flex it's collective amp muscle so to speak when you really need that extra power.

"All will come with time and experience, young Grasshopper"
 
Excellent post, you picked up some gaps I left... May I also mention that any time your inputs are consistently "running in the reds" or overloading your are actually shorting out your channel, mixer, or amp. Your system will react appropriately if it is intermittently blinking, so no worries, just back your levels down just a tad.

----
Another feature on most amps include a protection mode. Most great amplifiers that feature this have more than one use for this... Protects your amplifier if it is being overworked, stressed, overheated. Also input voltage is checked and if it is too low or two hi it will throw it into protection, additionally if a short is detected along somewhere in the cable it will trigger, thus preventing "grave damages". If the short protection didn't exist then you will find that many internal components will be burned to a crisp.

BTW Crown offers a 5 year no fault warranty for their products, you can essentially drop it from a 2 story building (not recommended) and still be covered under warranty. They make an awesome product, although I am a powered guy for mobile, larger rigs should be conventionally passive and powered by a amp.

(Bounce going on tangents again, somebody slap me)
 
Bounce said:
Excellent post, you picked up some gaps I left... May I also mention that any time your inputs are consistently "running in the reds" or overloading your are actually shorting out your channel, mixer, or amp. Your system will react appropriately if it is intermittently blinking, so no worries, just back your levels down just a tad.

----
Another feature on most amps include a protection mode. Most great amplifiers that feature this have more than one use for this... Protects your amplifier if it is being overworked, stressed, overheated. Also input voltage is checked and if it is too low or two hi it will throw it into protection, additionally if a short is detected along somewhere in the cable it will trigger, thus preventing "grave damages". If the short protection didn't exist then you will find that many internal components will be burned to a crisp.

BTW Crown offers a 5 year no fault warranty for their products, you can essentially drop it from a 2 story building (not recommended) and still be covered under warranty. They make an awesome product, although I am a powered guy for mobile, larger rigs should be conventionally passive and powered by a amp.

(Bounce going on tangents again, somebody slap me)
Click to expand...

***Corrals Bounce with a bitch-slap***:sqlaugh:

Not to derail the thread, but Crown makes some of the best and hardest working amps in the world. I have 3 old Peaveys (C-4, C 8.5) from back in da-day that I still use in one of my racks. It was once said that you could drop these off the tailgate of a moving pickup at 35 miles an hour and they would continue to kick butt.

**(I don't endorse any brand and/or recommend you try this)**

We now return to, "As The Gain Turns"........brought to you today by the number 4 and the letter H........:sqcool:
 
sparkieg said:
Loudspeaker - Fred and Bounce speak from experience. You can trust what they say. I have run live sound for bands, live theatre events,etc. from small and smoky bar rooms to 30,000 seat arenas. ALWAYS run your gain at full for maximum headroom. In your case, I would venture to say the largest attended event you would provide sound (right now) for would be a gym filled with 300+ high school kids.

If you run your amps with the gain at full, the signal that reaches those amps, once processed thru an E.Q. and active crossover, will most definitely be louder and cleaner than if you ran them at 12 o'clock with your mixer close to red-lining. When you red line the level on your mixer, you are already dis-coloring and distorting the sound before it even has a chance to be processed. True, when you run in this configuration, you will wind up running your master gain on your mixer output at maybe 2 or 3, but by doing this, you are giving your system a chance to breathe and flex it's collective amp muscle so to speak when you really need that extra power.

"All will come with time and experience, young Grasshopper"
Click to expand...

Thanks for the plain english definition. I really appreciate it. I guess I'll just have to miss those pretty dancing lights by the master volume knob. I've got an event coming up in a few weeks that we do every year for a non-alcohol fraternity (never knew these existed until I met these guys) they know how to party and they make me turn it up, I mean WAY up. I'm no wussie but I'm thinking about ear plugs for this thing!!! Did I mention Way UP!! I gues I'll get to see those pretty lights that night!
 
Fred Stewart said:
This is more of a unity gain issue. :)

Every professional processing component has gain adjustments. Not to be confused with level controls (channel sliders), gains should be set at unity for the best performance.

To start, set gains at center detent. Monitor your level LEDs or meters to ensure that you don't go out of the "yellow" or above desireable gain. Adjust so that signals are below the "red" for each component.

EQ settings should also be set to center detent at first. Tweak the EQ slightly to "ring" or reduce feedback from your mics. Otherwise, leave it alone.

Your power amps should be set to no attenuation (full) for maximum headroom. Output level is controlled at the mixer.
Click to expand...

Is that the same with the gains on "Active/Powered speakers. The disadvantage with the powered speakers is you don't have any meters on the speakers themselves, just the gains, so you can't see if you are pushing them to hard. I usually run them at 12:00. I use my crossover to control how much I send to the Speakers. I've been a little hesitant to run the (Tops) JBL EON's 15 speakers at max, but the power/gain settings on the JBL 18" powered subs I run at max. Should I be running the Tops @ Max?
 
I'm still really surpirsed about the answer of Turning the gain all the way up. Makes sence, just really surprised.

Can you ever send TOO much power to the speaker? What if I had a 5,000 watt amp on a 1,000 watt speaker?

Another one, Can someone explain headroom? Thanks
 
I guess that would be a case of lowering down the gains, but unless your really experienced and I mean really really I highly suggest against it, you could easily cook your system in a matter of seconds ... literally. It's always best to match your wattage on the speakers, depending on your setup, see the ohm chart that dj svo posted here, it will give you a better idea along with your amps instruction book. You know the chart saying what at what ohms.

Some users will typically spec their amps out just a little higher than what is rated at the speaker, "just a little" like no more than 1,000 watts more. They also have a limiter in place, as well as built in circuitry in the speaker, the JBL M-Pro series has such circuitry to prevent a dead speaker due to over-powering... It's similar to overclocking a PC, just because it CAN be done, doesn't mean it SHOULD be done. I wouldn't rely solely on the limiter, the gain on the amp, and the protection circuitry to protect the system, too many things that CAN go wrong.
 
sparkieg said:
"All will come with time and experience, young Grasshopper"
Click to expand...


Quickly as you can, snatch the pebble from my hand.

When you can take the pebble from my hand, it will be time for you to leave.
 

Attachments

  • kung fu.jpg
    kung fu.jpg
    1.9 KB · Views: 18
You must log in or register to reply here.
Top Bottom
Back