Which power amp for PA and nearfields?

  • Thread starter Thread starter James HE
  • Start date Start date
J

James HE

a spoonfull weighs a ton
I need an amp for my PA and my 20/20's. Can't afford two seperate amps so I need somthing that will do double duty...

I've got three prospects on my list so far (budget <>$400)

Mackie M-800
Yamaha XS250
QSC RMX850

I'm leaning toward the QSC... dunno why really, but the powerlights they had at the dance department at my school sounded great.

or maybe the mackie... I've only heard their powered mixer line which I thought was pretty noisy. (I love my Mackie mixer though)

I dont know anyhting about the Yamaha...

All the specs are pretty similar...

Any recomendations?

-jhe
 
Hafler.
Probably the best you'll ever hear for the money.
Low noise and very dependable.
Ask sonusman, he'll back me up on this.
 
Well, No Shit...

Seems kind of like overkill for my crappy PA sreakers though and a little pricy right. I'd like to eventually get a smaller Hafler just for the nearfields...

-jhe
 
Yeah doc, that's where I'm leaning toward for my events. I want more power for my PA - at least 200 watts per channel (or 400 bridged) at 8ohm. My PA head has to be replaced, it sucked anyway, but it got fucked up in the electrical storm. An old TOA head not worth $50. (new speakers would be good too...)

I think I'm sold on that QSC, it weighs like 40 pounds though! Thier lighter amps are $$$. So actually I think I'll just keep using my JVC reciever for my Events when I get it. Don't want to be lugging 40 pounds between rooms all the time. But I'll try it at least once on my events to test the difference. then maybe the hafler and I'll have a little shootout... (and the winner is... the JVC! just kidding... :D) Now I just have to paint enough houses to afford 'em!

-jhe
 
James HE said:
Yeah doc, that's where I'm leaning toward for my events. I want more power for my PA - at least 200 watts per channel (or 400 bridged) at 8ohm. My PA head has to be replaced, it sucked anyway, but it got fucked up in the electrical storm. An old TOA head not worth $50. (new speakers would be good too...)

I think I'm sold on that QSC, it weighs like 40 pounds though! Thier lighter amps are $$$. So actually I think I'll just keep using my JVC reciever for my Events when I get it. Don't want to be lugging 40 pounds between rooms all the time. But I'll try it at least once on my events to test the difference. then maybe the hafler and I'll have a little shootout... (and the winner is... the JVC! just kidding... :D) Now I just have to paint enough houses to afford 'em!

-jhe

James,

What kind of PA speakers are they, and what is their RMS ?

You want your PowerAmp to be TWICE the RMS rating.

You set the Power Amps inputs at 50% volume-this way your Amp delivers the speakers full load and it's CLEAN!

Speakers generally burn out from bein UNDERPOWERED- i.e, you drive an Amp at 100% and it's delivering a distorted signal to the speakers which in turn burns the Voice coil.
I ran sound for over 10 years, and burned up a few speakers before I learned that I was underpowering the system...

QSC's are great Amps. The Mackie's aren't bad, but I'd say go for a QSC.

Tim
 
Ouch....

Tim, you are on the right track here, except that the input sensitivity on the amp is changed when the volume control on the amp is turned, and this is not a good thing.

With your method there, the amp is actually more apt to create clipping at the input, which is the leading cause of blowing out speakers.

An amp that is 150% of the RMS at full volume is the best way to go. This is coming from a guy who has yet to blow a single PA speaker in over 14 years of live sound.....:)

Now JamesHE. How many times you gotta hear it from me? Buy cheap, but twice.

By a damn Hafler P-3000 and be done with it. Mine has stayed turned on 24/7 for most of the 3 1/2 years I have had it and it works perfectly.

You will be hard pressed to find a better sounding amp. Buy any other at your own risk.

Ed
 
Re: Ouch....

sonusman said:
Tim, you are on the right track here, except that the input sensitivity on the amp is changed when the volume control on the amp is turned, and this is not a good thing.

With your method there, the amp is actually more apt to create clipping at the input, which is the leading cause of blowing out speakers.

An amp that is 150% of the RMS at full volume is the best way to go. This is coming from a guy who has yet to blow a single PA speaker in over 14 years of live sound.....:)

Now JamesHE. How many times you gotta hear it from me? Buy cheap, but twice.

By a damn Hafler P-3000 and be done with it. Mine has stayed turned on 24/7 for most of the 3 1/2 years I have had it and it works perfectly.

You will be hard pressed to find a better sounding amp. Buy any other at your own risk.

Ed

Hi Ed,

Well-I haven't blown a single speaker since I started doing this.
I learned that one from a Guy who ran sound for YES during the 80's.
At that time, when most local bands were playing out their rig Generally consisted of a pair of 15" Scoops, a pair of 15" Perkins bins on top (hornloaded 15" 90x45's) and a 1" Horn. For power they would be running a pair of CS800's to drive all of it. The systems never sounded worth a crap, and that was what inspired me t learn about Live Audio.
Later I found out it was because everything was underpowered, because I used one of these systems with twice the power, and it sounded great...

By setting the Amps inputs at half volume-you've essentially backed the Amp's sensitivity off 10 db's allowing for peaks.(But you know this already)

The other option is to set the gain on the Amp at full volume and control the sensitivity via the crossover.

My whole problem with the Hafler's has been that they are low power (You have to remember that I have a 5K mains / 2K Monitors rig )
My only gripe is that when I bought these Community speakers (CSX series) everyone said-Oh they're plywood, not particleboard! Even one of the guys who worked there thought they were plywood! WRONG!
The subs (4x15" 1,600 watt peak @ 4 ohms) are Particleboard-which means the things weigh in around 200 lbs. each-not too much fun for 1 guy to lug around!
(The bitch is getting them into the Van by myself!)
That's the first time I've ever seen a speaker that was rated for 0.8 ohms! I was going to have a set of boxes built that I thought I would be able to wire at 8 ohms...there went THOSE plans! Hahahahaha

Tim
 
MY current PA speakers are crap. a pair of 12" sonics. What ever I put into them is going to sound a litte crappy. I'm not exspecting much, I just want to be able to hear the vocals and my acoustic gutar over the band when we are rehearsing. I's like to get some decent floor monitors (at some point) and run it all together. The old head was under 100 watts, which was not even close to being enough, but what wattage should I be looking at? I was thinking 300 to 400 should do. What do the 300 to 400 watt Haflers go for? really I've only seen prices for the lower wattage ones.

-jhe
 
I guess this just goes right back to my original response, huh?
Spend your money once, instead of being a numbskull like me and spending it twice :confused: ...that's all I was trying to say.
 
I was about to post a new thread, but this one seems on target for my question. I am thinking of buying a pair of Event 2020's. I already own a Crown PB-1 PA amp (240 watt into 4 ohm, 200 into 8 ohm)? To save money in the short run, can I use the PB-1 to drive the 2020's. Assuming I can, what am I sacrificing?

I've seen the 2020's for $269/pair at Zzounds. If I can use the PB-1, this is significantly less dinero that say the 2020bas for nearly $700.00. I guess I could later on get a Hafler TA1600 for another $200.00 (still less combined than the bas's). What say ye oh wise ones??
 
Back
Top