P.a

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Idgeit

Idgeit

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Hey all,

Im thinking about buying a PA instead of renting one for every show i put on, but im wondering, could anyone tell me how many watts i would need to carry the sound well for every differnt size pub i encounter on the way.

Im willing to spend around 700 euro

I was looking at this, http://www.netzmarkt.de/thomann/thoiw6_artikel-165208.html
would it be any good for the job?

On the power mixer it says "compact power mixer, 2x375W / 4Ohm, 2x200W/ 8Ohm", can anyone tell me what that means?
 
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Hi,

(Folks correct me if i'm wrong)
Compact powered mixer = active = amplifier is built in
With 40Ohm you have the two boxes which are in the set you want to buy. The 80 Ohm means that the amplifier can handle more boxes. 4 for example but that the watt will go down.

A question to you for how many people do you want to use the set??? For what purpose do you want to use the set???

greetz remco
 
Yes, powered mixer = amplifier built in. Past that, Wagemakers, you are thinking about it backwards.

First off, I'm a live sound guy that has recently gotten into recording. I don't know much about recording, but I've been involved in live sound for about 26 years. I'm also from the US and have never heard of the brands that we are talking about here. I have no idea if they are good or bad, but ohms law stays the same...

Anyway, the mixer's output is rated at 375wpc (watts per channel) at 4 ohms, and 200wpc at 8 ohms. The speakers are 8 ohms each. This means that the powered mixer will see an 8 ohm load on each channel and put out up to 200 watts to each channel, assuming one speaker is connected to each channel. This would mean that each speaker would see up to 200 watts.

If the speakers were 4 ohms each (which they are not), and connected them in the same manner, the mixer would see a 4 ohm load on each channel and put out up to 375 watts to each channel. Each speaker would then see up to 375 watts each.

If you were to purchase 4 of the 8 ohm speakers, and ran two speakers off each channel in parallel (daisy-chained together), the mixer would then see a 4 ohm load per channel and put out up to 375 watts per channel. This would mean that each speaker would see about 187 watts.

To clarify...

1: 4 ohms is MORE load than 8 ohms.
2: Amp will put out more power at 4 ohms than at 8 ohms.
3: Amp will run HOTTER (temperature) at 4ohms than at 8ohms.
4: Don't go below 4 ohms.

With all that being said...There just ain't no way that this little pa is gonna suffice for "to carry the sound well for every differnt size pub i encounter on the way." I won't get into all that, but if you ever plan to play anything bigger than a tiny coffee house, with more than an acoustic and one vocal, at anything louder than background music, forget it. If you think you can mic up a drum kit and bass, sorry, but that pa won't do it.

Buy GOOD stuff once. It's a lot less expensive than buying crap mulitple times until you finally give in and buy the good stuff in the end.

Stacey
 
Thanx Dagwood,

I knew I was wrong somewhere. No I understand it better. Thanx


Greez,

Remco
 
a while ago i was reading about this subject and seemed like
Peavy ps15 speakers are well-liked for small PA's,
i think they are 500 watt each

i think thats a good start if you want todo PA's for clubs that carry around 300 people... two speakers of 500 watt rms, 15" woofers to make sure the bottom end comes trough nicely,

then get yourself an amp that delivers ...i don't know... 400 watt per channel,
obviously not higher than your speakers to make sure you don't blow them...

i prefer to work with a sererate mixer, amps, and speakers,
i'm not such a big fan of mixers with built in amps...but thats me...
its easier to change a mixer, or amp, easier to upgrade to something else...

i worked with NEXO ps15's , but they're very expensive speakers, at least for a small guy like me.... what do they cost again;; 2000 euro each or something
,but of course i rent these...

i think you can get peavy ps15 or is it PR15 (if its the correct type) speakers for around €300 each
http://i19.ebayimg.com/03/i/04/2e/cc/f7_1_b.JPG
 
Shouldnt the amp be more powerful then the speakers so they dont have to work to draw power from the amp? For example if you have speakers that are rated at 300W rms, it is better to have an amp at least 300wpc and more if possible? Is that correct?
Thanks
 
i've heard that before,
if you get yourself an amp that is way more powerful than the speakers,
you just turn the volume up 50% or 75% and the amp has to work less hard,
so i guess it heats up less fast...

but then you might risc that you, (or someone else) turns the amp up too hard and you can blow speakers....
or you gotto make sure there's a decent limiter before the speakers...
but i guess thats only possible if you got XLR connections on the speakers and no speakon...

i've always used the "method" of using "stronger" speakers and a "softer" amp,
just to be safe...
 
BadAE said:
I have seen too many blown speakers because of this.
Read this http://www.jblpro.com/pub/technote/lowpower.pdf
Click to expand...

That is a good one, with the exception of the idea that increased high-frequency harmonic distortion is the cause of tweeter failure. That has been shown to be incorrect. I do not know why JBL leaves that paper up on their site uncorrected. It helps spread incorrect information and perpetuates the myth of distortion from clipping being inherently dangerous to speakers. If that was true, a lot of guitar amp and synth makers would be out of business.
 
It still is not a good idea to use an under powered amp to run your FOH speakers. Hi feq harmonic destortation may not be the cause of blown tweeter but what ever the explaination is, it is never a good practice.
 
BadAE said:
It still is not a good idea to use an under powered amp to run your FOH speakers. Hi feq harmonic destortation may not be the cause of blown tweeter but what ever the explaination is, it is never a good practice.
Click to expand...

:) The word of the day is clipping. Don't clip your amp. It is hard to keep your desire for volume under control with an underpowered amp sometimes, when you want "just a little more", especially "just a little more" low end.


http://www.rane.com/note128.html
 
stanjanssen said:
sorry: what does FOH mean?
Click to expand...

Front of House- where the mixer is, in front of the PA, out in the "house"- theater, club, whatever, as opposed to onstage or backstage. If you are lucky, you can actually hear the PA from there while you mix.
 
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