What Does The Red Peak Light Mean On My Amp When It Sometimes Comes On

[noris 0]

Hi Guys

 

I have a quick question and would be grateful for your input

 

On my amp the peak light sometimes goes red when i turn up the volume does this mean there is too much power going to it?

 

It doesn’t always do it just flicks on for less then a second through some of the songs. If it continues to do this does it mean it would damage the amp? mixer? speakers?

 

If i turn the bass down it seems to do it less

 

Is this what people mean by clipping?

 

Thanks

[poridge 0]

yeah this is the same as clipping. basically too much power is being drawn from the amp, when you turn the bass down it draws less power and therefore doesnt clip. and in theory if you continue to do this you could potentially damage your amp, always best to stay just below it.

 

im sure there will be other technicalities with this but these are pretty much the basics.

[Dukesy 0]

Yes

 

A basic way of explaining - the sound source is sending a signal that is distorted / making the amp work harder.

This is not good for the amp, the speakers or the ears!

 

The sound source (usually via the mixer) can be turned up or down via a gain / volume control.

 

When you add eq (bass, mid, treble) to a sound source, you are adding decibles which can distort / causing 'clipping'.

 

The clipping can be viewed on the mixer - when the level indicators are in the red.

 

To avoid clipping on the amp, turn down the sound source via the channel gain on the sound channel.

 

Your mixer may need an attenuator adjustment to your amp.

 

Note: If you are unsure how to adjust the Mixer/Attenuator usually found at the back of a mixer, speak to an experienced DJ / techie engineer as your sound system can be damaged if over compensated!!

 

[noris 0]

Thanks for the help

 

So if i want to stop this happening i need a bigger amp or bigger speakers?

 

Can i turn it to as loud as it will go before the peak light comes on without doing damage to the speakers? or is that the way of the amp telling me the speakers cant take any more power?

 

Maybe you can explain this to me why when my speakers are turned up and still sounding good the peak light is still coming on?

 

Thanks

 

Just to add to what i just said the mixer is within the green peak but the amp is still showing red now and then

[vokf 0]

Its probably best to let us know the make of your Speakers and Amp. If they are not suited (ie Amp is low power, speakers are high power) then this will influence the advice.

 

If your speakers are on the floor, then you'll get better levels to the crowd by simply investing in some speaker stands to get them head-height.

 

The occasional clip is ok - but if it were every beat, I would reduce something (level, or simply back off any Bass eq - if you've added it)

If the EQ is flat, and the levels are not enough for the gigs you do, then you'll probably need to upgrade your Sound system (or take smaller gigs)

 

 

 

[norty303 0]

A basic way of explaining - the sound source is sending a signal that is distorted / making the amp work harder.

 

Basic and a little misleading.

 

It is possible to drive an amp to clip/limit without the mixer clipping/distorting, it comes down to a number of factors, including input sensitivity on the amp and any pieces of kit in between that may be attenuating or boosting the signal. It's all related to proper gain structure.

 

If you have clip limiters on the amp and they are switched on then the peak light usually indicates them activating. If they are not switched on then the peak lights will indicate clipping. Hard limiting can still damage your speakers. The occassional flash should not present too many problems providing your amp isn't rated more than 2x the RMS rating of your speakers.

 

However, as with most things 'red = bad' so try to avoid the red lights. Unfortunately most rigs start to sound 'on song' with a few red lights flashing on the amps because they are getting decent power, and the temptation is often to keep going up. Thats when damage happens.

 

 

A good way to set up your gain structure is so that when red lights come on on the mixer meter, the amps are just starting to peak/clip. That way you know from looking at the mixer what the amps are doing.

To do this, first turn the amp gains all the way down, then play something through the mixer so that it just starts to hit the red lights on the mixer. Then turn the amp gains up slowly until the peak light starts to flash. Some people like to back them off slightly from this point for a small safety margin. Now you know that red lights on the mixer = red lights on the amp. You can still over drive the amp by cranking the EQ/gains so don't be fooled into thinking this is now safe to abuse. you also now have a situation where meddling hands could turn up the amp (as they're likely not in the full position after doing this)

 

The 'other' way around this is to run with the amps on full (impossible to turn them up further) and use something like a crossover/EQ/system processor in the middle to control the overall gain going to the amps. The benefits of doing it this way is that you can page lock/lock away the controller/EQ to prevent fiddling and still ensure red lights on the mixer = red lights on the amp.

 

You might also want to check whether your amp has an input sensitivity switch for the inputs. Many do. You can then run the mixer hotter by reducing the input sensitivity of the amp.

[noris 0]

Hello

 

Thanks a lot for the great replies

 

I will tell you what i have to make this a lot easier

 

 

 

Soundlab Amp SP500

 

Power Output: 250w Per Channel Into 4n

 

150w Per Channel Intom 8n

 

90w Per Channel Into 16n

 

Input Sensitivity:775mV 250W rms Into 4n

 

Frequency Response:10 Hz-30kHz +1db

 

Protection: Against Short Circuit,Open Circuit And DC Fault

 

Power: 230 VAC @ 50Hz 500A

 

Input Connectors: 2 x 6.35mm Mono Jack Plugs

 

Output Connectors: 2 x 4-Way Speakon

 

----------------------------------------------------------------------------

 

I also have 2 x Soundlab Bass Spins connected via the jack input on the amp

 

The speaker info is as follows

 

Peak Music Power 600watts

 

Impedance: 8ohm

 

Maximum Input Voltage

 

50 volts RMS

 

-------------------------------------------------------------------------

 

Then for main speakers i have

 

2 X Soundlab

 

Peak Music Power 1000watts

 

Impedance: 8ohm

 

Maximum Input Voltage

 

50 volts RMS

 

 

 

Can anyone advise if i have the correct amp for the correct speakers?

 

Thanks

[norty303 0]

Can anyone advise if i have the correct amp for the correct speakers?

 

Even assuming that connecting your tops and subs together makes them an 4R load, the amp is grossly underpowered for the job. Assuming that peak is 2x RMS on the speaker ratings, you have 800wrms power handling per side and only (at best) 250w to drive it with. If the internal crossovers preserve the 8R load then you only have 150w driving it. This is why it sounds good when the red lights start showing because it's only just really starting to work the drivers.

 

You could at the very least go to 500w per side and gain significant increase. Personally I'd go for 800w or more per side (at whatever load it is) but you may not have the money for it - although bigger amps are getting cheaper all the time. Try Thomann for a good deal.

 

Better still, buy an active crossover and 2 amps (or one big one and run tops off one side and subs off the other in mono until funds permit the second amp) and REALLY notice the difference fully active systems can make to the spl and sound

[noris 0]

Thanks for the great info norty303

 

Bear with me when i try to make sense of all this tec info

 

I am just trying to get my head around this so if i get an amp that outputs 1000watts would this be good enough?

 

The bit that i get confused about is the @ 2ohms, 4 ohms, 6 ohms, etc i dont understand what this means, rms?

 

I am sure this is incorrect but does it mean if i get a 1000watt amp and connect 4 speakers it will deliver 250w per speaker and if i connect 2 speakers it would deliver 500w per speaker? :)

 

A brief explanation yet easy to understand for a newbie of what @ ohms means would be grateful

 

Thanks again for your time

 

PS

 

 

 

 

This picture here is what confuses me on the back of my amp i have 4 speakons and 4 jacks so that tells me i have 4 places to plug speakers as it has 4 speakons. But this picture above is what most amps are like well at least the ones i have seen. i just dont understand why it has 3 speakons and not 4 who would want to run 3 speakers not in pairs?

 

Please don’t laugh :Thumbup:

 

I was just reading on the numark dimension amp does anyone know how that would sit with my above speakers?

 

I am just not sure how i would connect all 4 speakers as it only has 3 speakons where the amp i have now has 4

 

Would i have to run 2 speakers from the speakons and 2 from the XLR inputs?

 

Also is it ok to run both base bins from the same channel that way if it’s to much bass i can turn it down without interfering with my tops

 

Thanks

Edited July 15, 2009 by TonyB

[McCardle 1]

Most mixers tend to be able to push 2v + when the faders are at their full travel, regardless of their quoted output sensitivities. 0db tends to equal 775mv on most DJ mixers, although it can be as much as 1.23v on American or PA mixers. Even then, if you stick them on a 'scope there are still peaks which often push well above that.

 

Distortion isn't only limited to amplifiers though, depending on the quality of the internal components, mixers can also produce significant distortion into the signal chain if overloaded - either on their input side or too much enthusiasm at the master faders.

 

if i get an amp that outputs 1000watts would this be good enough?

 

You need to look beyond the watts rating to determine a decent P.A system. Yes, power output does play a part but it is the brawn in the equation, the brains side of it, comes from the quality of the amplifier and speakers, and also the sbl rating of the speakers.

 

A speaker with a higher 'sbl' rating will *usually* be of a higher quality, and is much more efficient at turnng each watt of power into actual sound pressure.

 

So if you find a speaker with a 123db spl, it will probably sound better, and slightly louder than a speaker with a 94db rating because it is far more efficient at producing sound from electricial energy supplied by the amplifier.

 

Bear in mind that some manufacturers exaggerate their spl figures, as they do their watts rating. So compare speakers on their continuous ratings, rather than anything quoted as maximum, peak, pmpo or short term

[norty303 0]

Basically, any decent speaker cabinet will have a few numbers associated with it:

 

Power rating/handling: This is normally quoted as RMS or Continuous and is the amount of power the speaker can cope with if fed a 'continous' signal e.g. a sine tone without burning up the voice coil. Sometimes it is quoted as Peak power which is generally 2 times RMS rating. As music is not a continuous sine tone, you should aim for an amp of between RMS and Peak values in power output, as the 'averaged' power present in modern music is about 2/3rds the peak value.

 

Impedance: The speaker will also have an impedance value (ohms). This is the 'nominal' load it presents to the amplifier, and will usually be 8R or in some cases 4R. If you measure an 8R driver across the terminals you'll actually find they're around 5.5R, but for simplicities sake we deal in nominal values. Also bear in mind that impedance changes with frequency and box tuning but thats an order of magniftude more complex than we should go into here. The impedance is important because it dictates how much power the amp provides at that impedance. Some people talk about running amps 'in 8R mode' or 'in 4R mode'. This is a misnomer as amps don't have modes, they simply have a load attached to them and make power that varies according to the load presented. E.g. an amp may be rated to produce 150w at 8R and 250w at 4R. If you connect a 4R rated speaker then it will receive 250w if run at max. If you connect 2x 8R speaker wired in parallel (which makes them a 4R load combined) then they will share 250w equally between them.

 

Sensitivity: Normally quoted as spl (sound pressure level) at 1W/1m (1 Watt at 1 metre). Basically its a measure of how much noise the speaker will make when fed with 1 watt and measured at 1 metre. Higher is better for outright SPL. It means that to achieve a given output level it needs less power than a speaker with lower sensitivity. In order to produce 3dB (decibels) more output, you need twice the power input.

Taking 2 examples, one speaker with 90dB at 1w/1m sensitivity and a speaker with 100dB at 1W/1m we can see the following:

Speaker 1

1w = 90

2 = 93

4 = 96

8 = 99

16 = 102

32 = 105

64 = 108

128 = 111

256 = 114

512 = 117

1024 = 120

 

Speaker 2

1w = 100

2 = 103

4 = 106

8 = 109

16 = 112

32 = 115

64 = 118

128 = 121

256 = 124

512 = 127

1024 = 130

 

So we can see that speaker 2 surpasses speaker 1 in outright SPL with only 128w input power, that speaker 1 requires over 1000w to achieve (if it can handle the power even!) Even then, at high power an effect called power compression comes into play whereby some of the input power is turned into heat rather than sound resulting in less than 3db gain for each doubling of power. You'll also see that speaker 2 goes on to make significantly more noise!

 

These might seem like extreme examples, however a good number of 'DJ' grade speakers are still in the 90db at 1W/1m range, whilst some moderately priced pro-audio cabs are getting onto the 100db at 1W/1m range. Not only could you save some money on amps by buying more sensitive speakers but they will likely sound nicer as they will be less stressed.

 

If you are familiar with a company called Funktion 1, they design speakers to have the greatest sensitivity, whilst not neccessarily having massive power handling (their 2x18" bass bins were only 450w rated drivers which is very low compared with some of the 1200w monsters out there now). However with clever design of horns they make the very best of these light cones.

 

If you want to know more about audio then try out the forum in my signature, there's a huge wealth of info there, including a newbie section that covers most stuff you're interested in.

 

I am just trying to get my head around this so if i get an amp that outputs 1000watts would this be good enough?

 

If thats 1000w PER SIDE at 4R then yes. I hate describing amps by their total power output for both channels, it's used by manufacturers to make them seem bigger than they are. A 1000w amp you're talkign about is really only 2x500w, which isn't really that big (but ONE THOUSAND sounds sooo much better doesn't it! :) )

As I said, i'd look for something in the 800w per channel at 4R range. Behringer, C-mark, Thomann T.amp, Tapco, etc all do something around that power. Once you get over 500w per side, the odd hundred watts here or there don't make too much difference. If you can find one, a second hand QSC PLX3402 (2 x 1100w at 4R) or 3002 (2 x 900w at 4R) will do the job perfectly, and only weigh 10kg. £400 - £500 should get you a good one, and it'll retain it's value. The 3402 was more popular therefore easier to find.

Edited July 15, 2009 by norty303

[Dukesy 0]

Thanks for the great info norty303

 

Bear with me when i try to make sense of all this tec info

 

 

Absolutely! It's amazing how much in-depth technical info there is available!

[noris 0]

Thanks very much norty303 for taking the time to write all that out

 

And thanks again to everyone who has taken the time to try and help

 

Thanks again