Need Help! What amp do I need for my speakers?

[MCM0726]

I need help deciding on what power mixer to use for my speakers. I have 2 CGM speakers (250W at 8 ohms) and a CGM stage monitor speaker (250W at 8 ohms). I don't want to under- or overpower my speakers.

I was using a Behringer Europower PMX 2000 (250W at 4 ohms in stereo mode). However, it quit working on me one day. Someone told me the problem might be the transformer. I connect each main speaker into the amp and the monitor into a monitor input on the front of the amp.

I want to purchase either a Yamaha or Peavey power mixer, but I need to know what kind of power I need to be looking for. If anyone has any idea or can help me, please let me know. I appreciate any help.

[ddouglass]

You need an amp that puts out no more than 200 watts per channel. If you go higher than your speakers are rated then you run the risk of blowing the speakers.

[Lonman]

What is the model number of the speaker for reference? Speakers will usually have 3 ratings, a RMS (continuous)/Program/Peak rating. 250 watts could mean one of those three, if it is the continuous rating you'd want an amp that puts out around 500 watts per channel into 8 ohms. If it's the program rating you'd want an amp that puts out 250 watts per channel into 8 ohms. If it's the PEAK rating, you'd want an amp that pushes 125 watts into 8 ohms. Rule of thumb to properly match your speakers is to get an amp that pushes at least twice the continuous rated power - 'program rating' (which the program power rating will generally tend to be double the continuous & the peak rating will be double the program) for maximum efficiency & headroom.
Looking at some CGM speakers it LOOKS as if the speakers program rating is 250-280 watts at 8 ohms, so get an amp that pushes this power per channel. But not knowing the exact model, can't be sure.
Sorry Doug, biggest mistake people make is to see a speaker rated at 250 watts continuous & get an amp that pushes that amount. What happens is the speaker can take much more. Say you are in a club & pushing the volume to a nice loud signal, well more people come in & the absorsion factor kicks in & now you need to kick the volume up higher, well the amp was already pushing at it's maximum clean signal of 250 watts, anything over that signal will now hit the speakers as distortion (clipping). You may not even really detect it audibly, but the speakers can feel it. This is the leading cause of speaker failure. You can blow a 100 watt speaker with a 10 watt amp, underpowering is bad!!! But on the same note, you wouldn't want to get an amp that pushes much more over the program rating of the speaker either.

[MCM0726]

The model is ARP-115H-1. I'm trying to do some research on this product, but it appears that CGM isn't an operating company anymore, or they've changed their name.

Do you know anything about this model?

[karaoke koyote]

Quality amps usually have a limiter on them to prevent you from overpowering your speakers. You should have at least 600 watts of power... if you are running a monitor you will probably need two amps. One for the mains and one for the vocal monitor (unless the monitor is self powered).

You need the power for reserve... not for volume. That way your lows are thumping, and your highs are crisp and not distorted. Thus a 600 watt amp is usually 300 watts per channel. Any more power and you'll blow people out of the bar.

Here's what I'm using:

ACESONIC AM-825

Look at the features of this baby, and I think you'll find it has everything a KJ could want and more. The sound quality is awesome, and with the speak on jacks, set up is a breeze. It has a pass through for your EQ or to add a sonic maximizer (although it has one built right in!!). I don't use an EQ with this at all... it has adjustments for lows, mids and highs, and with the BBE sonic maximizer I use an EQ would just get in the way.

If you use a laptop, it has a USB port for a direct digital audio connection (no digital to analog conversion!), and an S-video, composite video and RCA video jacks, as well as a VGA connection!!!!

I love this thing, and I looked all over the place, and could not find anything like it anywhere.... and it fits in a standard 19" rack!! Thus, you can prewire everything. Just plug in your speakers and your ready to go.

I didn't start out using a laptop, but now that I'm getting one I'm so glad I thought ahead an got this.

Acesonic is great to deal with, I've been using their karaoke player for over a year... also works great.

This amp also has a vocal line out for recording purposes. Just run the vocal line out to a second PA amp, and run the monitor from that. You don't need nearly as much power for the monitor. I'm using a 100 watt bridgable amp in mono. Works great.

Hope this helps!

[Lonman]

It's not necessarily a matter of blowing people out of the bar it's properly matching the amp to the speakers program rating for maximum efficiency & clarity - and less chance of possible blowing the speakers. If a speakers program rating is 500 watts, then that's what your amp should push. Yes it will make sound & even seem loud with a lower powered amp, but it's also increasing the possibility of driving the amp into clipping if the extra volume is needed plus it isn't going to be able to really push a nice full clean signal throughout the frequency range. More power will make regluar listening levels seem fuller & seemingly louder because of it meaning the system doesn't need to be turned up as loud to achieve the same effect.
The Acesonic is actually not a 300 watt per channel @ 8 ohms amp, they list that as the specs, but if you look it's actually a peak rating. The 4 ohms per channel RMS (continuous) rating is 200 watts per channel meaning the 8 ohm continuous rating is probably closer to 125-150 watts per channel.

[ddouglass]

Originally Posted by Lonman

What is the model number of the speaker for reference? Speakers will usually have 3 ratings, a RMS (continuous)/Program/Peak rating. 250 watts could mean one of those three, if it is the continuous rating you'd want an amp that puts out around 500 watts per channel into 8 ohms. If it's the program rating you'd want an amp that puts out 250 watts per channel into 8 ohms. If it's the PEAK rating, you'd want an amp that pushes 125 watts into 8 ohms. Rule of thumb to properly match your speakers is to get an amp that pushes at least twice the continuous rated power - 'program rating' (which the program power rating will generally tend to be double the continuous & the peak rating will be double the program) for maximum efficiency & headroom.
Looking at some CGM speakers it LOOKS as if the speakers program rating is 250-280 watts at 8 ohms, so get an amp that pushes this power per channel. But not knowing the exact model, can't be sure.
Sorry Doug, biggest mistake people make is to see a speaker rated at 250 watts continuous & get an amp that pushes that amount. What happens is the speaker can take much more. Say you are in a club & pushing the volume to a nice loud signal, well more people come in & the absorsion factor kicks in & now you need to kick the volume up higher, well the amp was already pushing at it's maximum clean signal of 250 watts, anything over that signal will now hit the speakers as distortion (clipping). You may not even really detect it audibly, but the speakers can feel it. This is the leading cause of speaker failure. You can blow a 100 watt speaker with a 10 watt amp, underpowering is bad!!! But on the same note, you wouldn't want to get an amp that pushes much more over the program rating of the speaker either.

Actually according to the "experts" you should be running your amp at about 75% (maximum peak effecieny before distortion begins to creep in) then control your volume through your input (mixer levels). That means you are pushing 150 watts from a 200 watt amp (I am referring to per channel and these are peak). I personnal use 500 watt RMS speakers with a 1000 watt Peak amp which gives me between 350 and 400 watts RMS to each speaker. This way I won't accidently blow my speakers and I have seen speakers that have had the woofer blown out....it isn't a pretty sight That is why I recommend getting speakers rated higher than the amp.

[MCM0726]

Thanks for all the info. I still don't know much about this speaker though. There isn't much information online. I found a site that has the ARP-112H-1 and lists it as having 140W RMS / 280W program. http://home.flash.net/~llbell/cgm.htm

Should I assume that the ARP-115H-1 allows for slightly higher numbers? The only thing is says on the speaker is 8 ohms / 250 watts. It doesn't say anything about RMS, program, or peak...

Thanks again for any help you can give. You guys seem to be very knowledgeable on this subject matter.

[MCM0726]

Again, the previous amp I used put out 250W per channel at 4 ohms. Occasionally, I would have the volume up loud enough to where it would start to clip (I guess that's what you call it). The meter would slightly hit the red, but only when I had it really loud.

So, I'm assuming that the mixer wasn't giving the speakers enough power. Which means, I should look for one that puts out 300W or possibly 600W per channel at 4 ohms.

Am I correct in this assumption?

[Lonman]

Originally Posted by MCM0726

Again, the previous amp I used put out 250W per channel at 4 ohms. Occasionally, I would have the volume up loud enough to where it would start to clip (I guess that's what you call it). The meter would slightly hit the red, but only when I had it really loud.

So, I'm assuming that the mixer wasn't giving the speakers enough power. Which means, I should look for one that puts out 300W or possibly 600W per channel at 4 ohms.

Am I correct in this assumption?

Look at the "8 ohm" ratings on the amp. Your speakers are 8 ohms. I would try to find an amp that puts out about 250-280 watts per channel for those speakers. Seeing that the 12" model is right around the same area. The 250 watts is most likely where you will want to be.
Yes when the little red light starts blinking this is the indicator for clipping - and most likely it was probably on the bass drum hits.

[Lonman]

Originally Posted by ddouglass

Actually according to the "experts" you should be running your amp at about 75% (maximum peak effecieny before distortion begins to creep in) then control your volume through your input (mixer levels). That means you are pushing 150 watts from a 200 watt amp (I am referring to per channel and these are peak). I personnal use 500 watt RMS speakers with a 1000 watt Peak amp which gives me between 350 and 400 watts RMS to each speaker. This way I won't accidently blow my speakers and I have seen speakers that have had the woofer blown out....it isn't a pretty sight That is why I recommend getting speakers rated higher than the amp.

I have been running sound for quite a while & have always been taught get an amp to push double the speakers continuous rating (which is generally the Program rating).
Here are some articles and tech tips from well known sources regarding properly matching speakers to amps - links are for informational purposes only.

http://www.sweetwater.com/shop/live-...ying-guide.php

http://www.prosoundweb.com/install/c.../primer3.shtml

http://www.musiciansfriend.com/docum...450&s=articles

I have blown speakers in the past, froze up a sub a couple years ago, but it was because I was running an amp that was lower than it's program rating. It called for 1200 watts @ 4 ohms, the only amp I had at the time was pushing 600 watts into 4 ohms. Sure it sounded fine, got loud - but the amp was being driven to clipping on this particular night & low & behold - poof! That amp came out, the new amp went in, got the sub repaired & it is now being driven by a 1400 watt into 4 ohm amp. The sound is alot fuller, & it doesn't need to be turned up nearly as loud from my mixer as I used to.

[MCM0726]

Awesome, thanks for the help. I'm looking into this mixer. Check it out if you want & see if it matches what I should be looking for.

http://www.musiciansfriend.com/produ...xer?sku=630181

Thanks again, everyone!

[Lonman]

That mixer is rated at 215 watts into 8 ohms, slightly underpowered, but not too much to make a huge factor.