difference between mixer & amplifier

[timo13-2]

We run a mobile dj business. Is it necessary to have both an amplifier & a mixer with a system? What is the difference between the two?

[Bobbsy]

I hope you mean you're "thinking of starting a Mobile DJ business" if you're trying to go about it without either an amp or a mixer!

 

The quick answer is that yes, you do need both.

 

The mixer does what it says--it takes your sources (probably two decks and a microphone for a DJ) and allows you to mix among these sources (say two tracks beat-matched while you speak over them. Your three sources are mixed together and put out on a single stereo pair. Most mixers also have other features (such as letting you preview one deck while listening to the other or adjust the "tone" of your sound) but those aren't important to this question.

 

In terms of electrical power, what comes out of the mixer is probably about a tenth of a watt, probably considerably less. (Experienced users will be cringing as I say this because we would normally measure a mixer's output in exotic units like "dBu" and such.) In any case, this might be enough to listen to on earphones but it certainly won't be enough to give a gut-thumping bass to a room full of 500 people.

 

The amplifier also does what the name says. It takes the relatively low signal and amplifies ("makes it louder") it up to the level required to drive your speakers so your adoring audience can hear you and your music. How much is it amplified? How long is a piece of string? However, even cheapie amp from Behringer or Thomann is probably going to take your tenth of a watt (line level) signal and make it into 500+watts with many, many thousands of watts being the norm for big shows.

 

Now, just to confuse you, you may see some systems that APPEAR not to have an amplifier. However, this is because the amplifier is, in fact, built in to either the mixer or the speakers themselves (known, strangely enough, as powered mixers or powered speakers). However, you still have a system that consists of Sources-Mixer-Amplifier-Speakers.

 

I should say that it's rare to find a system this simple. Even basic DJ systems often have multiple amplifiers driving multiple speaker cabinets, most notably extra ones giving the super low sub-bass notes that the punters love so much. Doing this also means adding boxes to control what sound goes to what set of speakers, equalisers (sort of tone controls) to adjust how everything sounds and so on.

 

Hope this helps. I might suggest some reading up on live sound systems--the FAQ section has some recommended books.

 

Bob

[boatman]

We run a mobile dj business. Is it necessary to have both an amplifier & a mixer with a system? What is the difference between the two?

 

You will find many people with a much better level of understanding of your problem here.

[showman]

Hello timo13-2, welcome to Blue Room,

 

Bobbsy's reply is a good summary... You could always see here on the blue room wiki on mixing desks. And here for FAQ's on sound and sound equipment.

 

Hope this helps.

[mirali]

Hi, Thank you for the explanation! Very well put.

 

I do have one question that keeps throwing me off.

 

I have a VocoPro DA-3700 Pro 200W Digital Key Control Mixing Amplifier that I use at home and occasional gigs. It does everything well with just one issue. When I record from this unit, the vocals don't sound right on phone speakers (iPhone or other). The vocals sound great when played through the headphones or a car or home theater system. Essentially, any system with two or more speakers, the vocals sound great (stereo effect). Since a phone has only one speaker, the vocals sound completely flat.

 

I've reached out to the tech support guys over at VocoPro but they didn't have much to offer.Any suggestions? Do I need a mixer to "mix" the music and vocals to a single stereo channel before I record? Hope this makes sense.

 

You can try listening to this simple test file (mp3) on your phone with and without headphones to see the difference.

 

https://drive.google.com/open?id=0B-rMTfceMT7lZDRKZ3NXb0Q4eTQ

 

Thanks!Mir

 

 

I hope you mean you're "thinking of starting a Mobile DJ business" if you're trying to go about it without either an amp or a mixer!The quick answer is that yes, you do need both.The mixer does what it says--it takes your sources (probably two decks and a microphone for a DJ) and allows you to mix among these sources (say two tracks beat-matched while you speak over them. Your three sources are mixed together and put out on a single stereo pair. Most mixers also have other features (such as letting you preview one deck while listening to the other or adjust the "tone" of your sound) but those aren't important to this question.In terms of electrical power, what comes out of the mixer is probably about a tenth of a watt, probably considerably less. (Experienced users will be cringing as I say this because we would normally measure a mixer's output in exotic units like "dBu" and such.) In any case, this might be enough to listen to on earphones but it certainly won't be enough to give a gut-thumping bass to a room full of 500 people.The amplifier also does what the name says. It takes the relatively low signal and amplifies ("makes it louder") it up to the level required to drive your speakers so your adoring audience can hear you and your music. How much is it amplified? How long is a piece of string? However, even cheapie amp from Behringer or Thomann is probably going to take your tenth of a watt (line level) signal and make it into 500+watts with many, many thousands of watts being the norm for big shows.Now, just to confuse you, you may see some systems that APPEAR not to have an amplifier. However, this is because the amplifier is, in fact, built in to either the mixer or the speakers themselves (known, strangely enough, as powered mixers or powered speakers). However, you still have a system that consists of Sources-Mixer-Amplifier-Speakers.I should say that it's rare to find a system this simple. Even basic DJ systems often have multiple amplifiers driving multiple speaker cabinets, most notably extra ones giving the super low sub-bass notes that the punters love so much. Doing this also means adding boxes to control what sound goes to what set of speakers, equalisers (sort of tone controls) to adjust how everything sounds and so on.Hope this helps. I might suggest some reading up on live sound systems--the FAQ section has some recommended books.Bob

[Jivemaster]

Sometimes a simple summing of L & R audio will cancel out parts of the signal and you get bits of the sound missing. Ask for help on mobiledjforums, they usually love talking about gear.

[Shez]

Essentially, any system with two or more speakers, the vocals sound great (stereo effect). Since a phone has only one speaker, the vocals sound completely flat.

That "stereo" effect is just achieved with some phase reversal trickery. As you've discovered, if the stereo is summed to mono, the effect cancels out. Other than sticking to the mono effect, there's very little you can do. The stereo one isn't "mono-compatible" so it'll never work through a mono sound system.

[MarkBarl]

With absolutely no offence intended and tongue firmly in cheek, I was under the impression that it is perfectly normal for a DJ's vocal to be unintelligible.

[sleah]

With absolutely no offence intended and tongue firmly in cheek, I was under the impression that it is perfectly normal for a DJ's vocal to be unintelligible.

 

Requirement isn't it? Along with the horribly distorted and clipped music with so much top end it could etch glass! ;)