pa system: more power?

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apodos

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I play in a rock band which will play small venues(parties/bars/restaurants/maybe small outdoor venues); we don't need to play for hundreds of people but we'd simply like the vocals to be loud enough to be easily heard above a nice, reasonable level of electric guitar,bass, keyboard and drums.

So I Recently purchased a pa system(phonic powerpod 780 with s715 speakers) with about 200w per channel at 8 ohms and found that it is difficult to hear vocals well above drums/bass/guitar; vocal levels are put as high as possible until feeding back....but still seems like they should be more easily heard; I DO notice that singing very close to the mic makes a considerable difference in volume...but should this be necessary?

I know that there are better quality brands of pa systems but I don't see why they would be any louder....unless, of course, one buys a pa system with more power...but many "quality" pa systems have the same power(200-300w @ 8 ohms per channel).
It seems that if one wants more power per channel, there is a considerable increase in price.

So my questions: 1-Should a rock band playing for friends and small venues need more than 200w per channel/speaker @ 8 ohms to get vocals easily heard? Is it common knowledge that during live performance for rock bands, a vocalist must sing with mouth on mic?

2-Would a better "quality" pa system give better/louder/cleaner vocal sound at the same power output?(eg.mackie vs. phonic?)

3-Is it feasible to add an external power amp to my current system of powered mixer/unpowered speakers?(I assume the power amp goes in between the mixer and speakers?)

Thanks
 
apodos said:
1-Should a rock band playing for friends and small venues need more than 200w per channel/speaker @ 8 ohms to get vocals easily heard? Is it common knowledge that during live performance for rock bands, a vocalist must sing with mouth on mic?
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This depends on how loud your guitars and drums are when you play. If everything is kept at a moderate volume then this should be enough power for just vocals. And, yes, it is common for vocalists in loud bands to keep their lips touching against the mic while singing. It is the best way to keep all other noise out of the mic.

apodos said:
2-Would a better "quality" pa system give better/louder/cleaner vocal sound at the same power output?(eg.mackie vs. phonic?)
Click to expand...
The brand and quality of the PA shouldn't matter as much as proper usage and placement of the parts. First and foremost, the speakers should always be kept well in front of the performers and pointed away so that the sound from the horns cannot travel toward the microphones. This is the most common cause of feedback. With feedback under control, you should be able to get higher volume levels out of the system. Also don't make extreme EQ adjustments. The EQ is intended to tweak problem frequencies. It is not intended to completely reshape and enhance crappy vocals into a superstar makeover. In general, when the EQ settings are left at center line or zero, things will sound most natural.

apodos said:
3-Is it feasible to add an external power amp to my current system of powered mixer/unpowered speakers?(I assume the power amp goes in between the mixer and speakers?)

Thanks
Click to expand...
If you add an external power amp then you must bypass the built-in power amp. If your system has a jack labeled "Pre-amp Out" that is what should feed the new amp.

I doubt you will see as much improvement from a new amp as you expect. You will see bigger improvements by learning proper usage techniques.

The most important thing to understand is distortion. If your speakers sound somewhat gravely or fuzzy, you are doing something very wrong, as far as levels on the mixer, and will likely cause speaker damage.

Read the manual, read up on "gain structure," and experiment with settings. In general, the main output fader should be at zero, unity, or close to full up. The channel faders should also be at or near zero or unity. The mic gain (or trim) at the top of the channels should only be turned up if absolutely needed due to very weak signals. But approach these settings slowly to be safe.
 
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If the vocals are as loud as possible before feeding back, getting a more powerful setup isn't going to help. The vocals will still feed back at the same point.

The key to reducing feedback is speaker placement and mic technique. You may have to get used to singing a little closer to the mic than you're used to.

How were the speakers set up?
 
that helps....thank you so much
if I might go a bit further.........

I'm looking at powered mixer with 220w per channel @ 4ohms and a bridged mono mode of 440w @8 ohms; speakers will be 8 ohms each.

My previous system had same speakers but the mixer was 200 ohms per channel @ 8 ohms.

My question is this:
I know that If I daisy chain the two 8 ohm speakers in bridged mono mode with the new system, I should have 4 ohms of impedance total but I'm not clear on how much power each speaker will see; I believe it should be more than 220w each because the total bridged mono power is 440w and if the total impedance is lowered the power should be higher? Does power go up in inverse proportion to impedance or is there a more complicated relationship?

I don't need different mixes from the main speakers, so I figure that a bridged mono mode will be fine here to get more power than I had before. Or is there some other good reason to avoid relying on bridged mono mode?

Thank you
 
Now that I have taken a look at that mixer, I see it doesn't have faders and trim knobs. (Sorry Dude)

In that case, never let the channel level knobs get higher than the main volume knob.

Does that make more sense?
 
apodos said:
that helps....thank you so much
if I might go a bit further.........

I'm looking at powered mixer with 220w per channel @ 4ohms and a bridged mono mode of 440w @8 ohms; speakers will be 8 ohms each.

My previous system had same speakers but the mixer was 200 ohms per channel @ 8 ohms.

My question is this:
I know that If I daisy chain the two 8 ohm speakers in bridged mono mode with the new system, I should have 4 ohms of impedance total but I'm not clear on how much power each speaker will see; I believe it should be more than 220w each because the total bridged mono power is 440w and if the total impedance is lowered the power should be higher? Does power go up in inverse proportion to impedance or is there a more complicated relationship?

I don't need different mixes from the main speakers, so I figure that a bridged mono mode will be fine here to get more power than I had before. Or is there some other good reason to avoid relying on bridged mono mode?

Thank you
Click to expand...

Again, if you are getting feedback at low volumes then the power amp is not your problem. You can upgrade to the biggest amp on the planet and you will still have feedback at low volumes.
 
Initially the setup was in a small room(garage) with less than ideal placement...mics in view of fronts of speakers.

But then I tried setting up alone in a large room in my home and put the mic well behind the speakers; if I turn the master volume up 3/4 , then gradually bring the channel volume up I get feedback about 3/4 of the way up. The vocal volume just doesn't seem as loud as I'd hoped but I have little experience with pa systems.

I have read that this system feeds back a lot but that might be hearsay; I'm talking about a phonic powerpod with s715 speakers by the way. I've heard the system works well outdoors, which would go along with what you've been telling me about feedback
 
I also wanted to mention that if I eq out the bass on the vocals, the feedback is somewhat minimized. If bass is not eq'd down than feedback happens pretty low on the volume level. But I'd rather not eq much and change the sound drastically.
 
What mic are you using?

I concure with all the other posters, it's not an issue of not enough power, more one of too much power for the room and the mic.
Moving from one tiny room to a different small room doesn't really prove performance at an actual venue... unless your performing in some elses living room.

The mic is picking up too much ambient noise, if your mic is well behind the speakers, than it's from reflections off the walls, if this was a rehersal space you could hang moving mats, blankets, treament on the walls to deaden the reflections... but hardly worth the bother to test your PA...

You can EQ with a notched sweep on a couple of problem frequencies (the narrower your Q, the less percieve difference in the output sound).. or you can buy a feedback buster that will do this automatically.. or you can try standing in the doorway/hallway just outside the room to see how much volume you could attain in a larger venue without reflections off of close walls.
 
I've had the same feedback issue with the following mics: shure sm-57, behringer xm8500 and shure ksm32 so I have my doubts about the mic being the issue.

In response to Gherkin's comment, my issue is that the mics feedback BEFORE getting as loud as possible. This is why I wonder whether a more powerful amp would give more volume before feeding back....I'm probably wrong but just wanted to verify.



And could someone apply his expertise to my question regarding bridged mono mode and effective power output: 440w @ 8 ohms in bridged mono going into two 8 ohm speakers which will be daisy chained gives X watts of power to each speaker?
 
If you can find more sencitive speakers you won"t need a bigger power amp ,
your s715 speakers are 98db speakers , if you can find some 101db speakers it will sound twice as loud....

Also your PA (phonic powerpod 780) can also drive 4 ohm loads so with 4 ohm speakers you can allmost double your output power (the specs say 300W into 4ohms) ....

So if you can find some 4 ohm PA Speakers with 101db sencitivity you will have an output power over 50% higher with a percieved loudness of over 300% of what you have now, so it would sound like 600w instead of 200w if useing the 98db speakers....

Cheers
 
apodos said:
I'm probably wrong but just wanted to verify.
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I'd consider this verified...
RawDepth said:
I doubt you will see as much improvement from a new amp as you expect. You will see bigger improvements by learning proper usage techniques.
Click to expand...
Gherkin said:
If the vocals are as loud as possible before feeding back, getting a more powerful setup isn't going to help. The vocals will still feed back at the same point.
Click to expand...
Rawdepth said:
Again, if you are getting feedback at low volumes then the power amp is not your problem. You can upgrade to the biggest amp on the planet and you will still have feedback at low volumes.
Click to expand...
MOFO Pro said:
it's not an issue of not enough power, more one of too much power for the room and the mic.
Click to expand...
 
MOFO Pro said:
440 watts ;)
Click to expand...

2 speakers hooked up to a 440w Bridged mono with still only put out 220w each speaker (440w total)....

But how are you going to wire 2 speakers?? In bridged mode you have to run a total of 8ohms Pluss but with 2 8ohm speakers you have to wire it as 16 ohms (series) which means you will acually get less power because 440w into 8 ohms is only 220w into 16 ohms....
 
Minion said:
2 speakers hooked up to a 440w Bridged mono with still only put out 220w each speaker (440w total)....
Click to expand...
Yeah just re-read the confusion... I thought the was starting with two channels of 440 watts... my intent was to explain that he'd wind up at square one for all the effort...

but I think it's a lot of wasted effort to get more power out of a system with uncontrolable feedback at it's current power... he'll just wind up turning the gain down...
 
apodos said:
I play in a rock band which will play small venues(parties/bars/restaurants/maybe small outdoor venues); we don't need to play for hundreds of people but we'd simply like the vocals to be loud enough to be easily heard above a nice, reasonable level of electric guitar,bass, keyboard and drums.

So I Recently purchased a pa system(phonic powerpod 780 with s715 speakers) with about 200w per channel at 8 ohms and found that it is difficult to hear vocals well above drums/bass/guitar; vocal levels are put as high as possible until feeding back....but still seems like they should be more easily heard; I DO notice that singing very close to the mic makes a considerable difference in volume...but should this be necessary?

I know that there are better quality brands of pa systems but I don't see why they would be any louder....unless, of course, one buys a pa system with more power...but many "quality" pa systems have the same power(200-300w @ 8 ohms per channel).
It seems that if one wants more power per channel, there is a considerable increase in price.

So my questions: 1-Should a rock band playing for friends and small venues need more than 200w per channel/speaker @ 8 ohms to get vocals easily heard? Is it common knowledge that during live performance for rock bands, a vocalist must sing with mouth on mic?

2-Would a better "quality" pa system give better/louder/cleaner vocal sound at the same power output?(eg.mackie vs. phonic?)

3-Is it feasible to add an external power amp to my current system of powered mixer/unpowered speakers?(I assume the power amp goes in between the mixer and speakers?)

Thanks
Click to expand...

I told you so. It doesn't pay to be cheap. https://homerecording.com/bbs/showthread.php?t=277114
 
thank you again for the info


I read the following from musiciansfriend's tech support section and this is where I got the impression that hooking two 8 ohm speakers together in bridged mono mode would work in this scenario; again, my bridged mono mode would give 440watts and I figured that I'd get 220 watts to each 8 ohm speaker by hooking them together(daisy chaining?) with their 1/4 input/outputs, reducing the impedance to 4 ohms.
See below:

Without going into a drawn-out technical explanation, here's what happens:

When you connect speakers of the same impedance, divide the rating of the individual speakers by the number of speakers to get the overall impedance load. For example, two 8-Ohm speakers will result in a load of 4 Ohms (8 Ohms ÷ 2 = 4 Ohms). Daisy-chaining four 8-Ohm speakers will result in an overall impedance of 2 Ohms (8 Ohms ÷ 4 = 2 Ohms).
 
I'm intrigued by the thought about getting 4 ohm speakers with better sensitivity.
I'm so grateful for this info as I can't seem to get it from anywhere else.
Thanks
 
Hi guys
I have just brought the Phonic Powerpod 740 plus.

As I do coffeebar gigs I am just using one speaker (Yamaha S112IVN) 300 watts rms.
I have put it on the bridged mono at 8 ohms .

Its a real great mixer has a nice solid sound , I use oiutboard effects . The TC Electronic 350, Reverb set on vocal hall and the delay set on dynamic delay.
I must say I am well happy with the sound.

Dave
 
Are you using that KSM32 live in small venues, while everyone is playing, loud, and wondering why you're getting "premature" feedback?

Paj
8^?
 
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