Is Nady 135 watt pa enough?
Is Nady 135 watt pa enough?
I have a very adequate system that I use, but a friend is intrested in purchasing her own for another town. I have played at the club she wants to play at. Its not much bigger than a typical corner bar. She asked about a Nady 135 watt pa system, with two 15" speakers. I told her I thought it would be sufficient, and that she may have to push it close to max output possibly on occasion. What is your opinion?
Amplifier wattage needs are determined by the wattage required by the speakers. 2 - 300 watt speakers need 300 watts (at the very least) per side on a stereo amp.
If a speaker is a 300 watt minimum and 700 peak, it needs 300 watts to operate correctly. Under powering a speaker is just as destructive as over powering. So I would say 135 watts is good for your car or maybe your livingroom or a phone booth, that's it.
If a speaker is a 300 watt minimum and 700 peak, it needs 300 watts to operate correctly. Under powering a speaker is just as destructive as over powering. So I would say 135 watts is good for your car or maybe your livingroom or a phone booth, that's it.
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cowboydarryl
- Posts: 40
- Joined: Thu Mar 22, 2007 9:27 pm
- Location: Hartford wisconsin
I have to agree with big dog. I also play a small bar,and im running mackie sa1530z's at 1300 watts each I have plenty of head room. 135 watts is way under powered. spend the extra money and get a good amp you will save your self money in the long run! not to sure about the quality of nady?? awfull cheap price usually comes comes with poor performance. at 135w she would berunning it flat out every time out.
Two 15" Woofers and only 135Watts total power? That doesn't sound right. Maybe more like 135W per channel (2 channels so 270W). Either way as Big Dog and Darryl have pointed out, pretty weak if you're trying to fill even a typical dive bar with people in it. Empty room, it would probably do fine but hopefully you're not playing to an empty room.
A real quick lesson in picking PA equipment. The speakers and Amps each have their own power rating. The speakers tell how much power they can handle, the amp tells you what it can deliver. Speakers usually have two specifications their RMS (Average) rating and the peak rating. When you pick an Amp for your speakers, ideally you want to get one that delivers twice the power of the RMS rating on your speakers.
So if I have two 15" speakers that are rated at 350W RMS and have an impedence of 8ohms, I would want an amplifier that can deliver 700W per channel (2 channels) at 8 ohms. Be sure you watch the impedence ratings of your speakers as that is also important for determining the power the amplifier can deliver. Most 2-way full range systems are 8 ohms but there are some exceptions.
So now that I've probably confused you completely.....
A real quick lesson in picking PA equipment. The speakers and Amps each have their own power rating. The speakers tell how much power they can handle, the amp tells you what it can deliver. Speakers usually have two specifications their RMS (Average) rating and the peak rating. When you pick an Amp for your speakers, ideally you want to get one that delivers twice the power of the RMS rating on your speakers.
So if I have two 15" speakers that are rated at 350W RMS and have an impedence of 8ohms, I would want an amplifier that can deliver 700W per channel (2 channels) at 8 ohms. Be sure you watch the impedence ratings of your speakers as that is also important for determining the power the amplifier can deliver. Most 2-way full range systems are 8 ohms but there are some exceptions.
So now that I've probably confused you completely.....
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alfalfa4381
- Posts: 28
- Joined: Sat Oct 11, 2008 11:06 pm
If your speaker is rated at 300 watts, and you pump 700 watts into it, you will "blow" the speaker. BUT, you still need a power amp rated at least as high as the speaker, but preferrably much higher, as stated above. You could easily have a 1500 watt amp driving the speaker. Why? Because it is CLEAN power that matters most. Consider this - the correct way to drive a high quality component power amp, such as a Crown, Mackie, etc., is to CRANK THE GAINS ALL THE WAY UP. This gives you maximum headroom on the mixer board. It will not hurt your speakers unless you apply too strong a signal at the amp's inputs. With no signal applied to the inputs, there is no power (watts) applied to the speaker.
The REAL problem with an under-powered sound system is distorsion. Here is what will happen: You will crank up your power amp's mains all the way. That's good, as described above. Next you will feed a signal to your mixer's input and push the mixer's master faders and channel faders (or knobs) to the desired listening volume. But, with only 135 watts and a lot of loud people in the room, you need more volume. So, you drive the mixer too hard, trying to get enough volume, so it "clips". This produces a distorted "fuzzy" sound in your speakers. It is this distortion that could ruin your speakers. This distorsion is a clipping of the peaks of the sine wave. The more the clipping, the more the sine wave becomes a square wave. The more "square" a waveform becomes, the closer to DC current the input signal becomes, and it is DC current along with added harmonics that can cause damage. Guitar amp speakers are designed to deal with heavy distorsion, they have high power ratings, heavier voice coils, and no tweeters or crossovers in their design. PA systems, on the other hand, are designed to accurately reproduce music and voice, using woofers, tweeters (horns) and a crossover network to pass the correct frequencies to the different components. They are more delicate and prone to destruction from distorsion.
Now, consider this. Distorsion can easily happen even with plenty of power. Most mixers, guitar amps, etc., have a master volume (Mains) and pre-amps (Channel faders, or knobs on a guitar amp). Guitar players get distorsion intentionally by overdriving the pre-amp by barely cracking the master volume and turning the channel volume all the way up. You have a few pre amps in your sound mixer. The input sensitivity, sometimes called the TRIM pot, is the first. The second is the channel fader or knob. You also have the ability to overdrive your aux busses by driving the cannel auxes harder than the master aux. So, for clean sound, be aware of the order that you adjust your sound. Here is what I do: Your very first chance for distorsion could be your wireless mic. Most of them have trims that need to be adjusted with a little plastic screwdriver. I adjust my trim only once on my wireless. I put in a brand new battery and sing VERY loud very close to the pop screen, to emulate what the very worst screeming karaoke singer would sound like, and adjust the trim back until there is no distorsion. This way, almost everything else that hits this mic will not be enough to overdrive it. Remember headroom? If I have plenty of power, and I am properly running my board, I can hear a gnat breathe in this mic if I need to because I can compensate using the next control. That is the input trim on the mixer (trim pot), which I adjust while singing at a normal volume, to where it starts to clip, usually indicated by a clip LED or VU meter. I then back the trim off a tad so the clip light does not flicker. Now I am giving the mixer the maximum clean signal for that input device, whether it is a mic or mp3 player, cd player, etc. Next, I push the cannel fader for that channel to 0 VU, or on my Mackie about 3/4 of the way up. I do this for all inputs that I am using, and then lastly I push the MAINS to the desired listening volume. Note that input signals change in strength, so you may need to adjust the TRIM pot on the mixer to compensate. A timid shy girl singing a soft song will probably require you to crank up the trim so you can get your headroom back. If the next person up is Elvis, you will need to adjust the trim down some.
I hope this was not too confusing, but the A#1 rule in getting clean, clear, powerful, GREAT sound is having enough power so the power amp is only coasting! Keep in mind that the discussion on distorsion and speaker damage is contorversial, many audio engineers differ in opinion on this matter.
Having been in the audio business for over 30 years, this subject has become my pet peeve. I have taught audio mixing and sound engineering classes just because I am passionate about good sound. Nothing makes me cringe more than hearing a nice sound system sound crappy because the operator does not know how to adjust it properly.
The REAL problem with an under-powered sound system is distorsion. Here is what will happen: You will crank up your power amp's mains all the way. That's good, as described above. Next you will feed a signal to your mixer's input and push the mixer's master faders and channel faders (or knobs) to the desired listening volume. But, with only 135 watts and a lot of loud people in the room, you need more volume. So, you drive the mixer too hard, trying to get enough volume, so it "clips". This produces a distorted "fuzzy" sound in your speakers. It is this distortion that could ruin your speakers. This distorsion is a clipping of the peaks of the sine wave. The more the clipping, the more the sine wave becomes a square wave. The more "square" a waveform becomes, the closer to DC current the input signal becomes, and it is DC current along with added harmonics that can cause damage. Guitar amp speakers are designed to deal with heavy distorsion, they have high power ratings, heavier voice coils, and no tweeters or crossovers in their design. PA systems, on the other hand, are designed to accurately reproduce music and voice, using woofers, tweeters (horns) and a crossover network to pass the correct frequencies to the different components. They are more delicate and prone to destruction from distorsion.
Now, consider this. Distorsion can easily happen even with plenty of power. Most mixers, guitar amps, etc., have a master volume (Mains) and pre-amps (Channel faders, or knobs on a guitar amp). Guitar players get distorsion intentionally by overdriving the pre-amp by barely cracking the master volume and turning the channel volume all the way up. You have a few pre amps in your sound mixer. The input sensitivity, sometimes called the TRIM pot, is the first. The second is the channel fader or knob. You also have the ability to overdrive your aux busses by driving the cannel auxes harder than the master aux. So, for clean sound, be aware of the order that you adjust your sound. Here is what I do: Your very first chance for distorsion could be your wireless mic. Most of them have trims that need to be adjusted with a little plastic screwdriver. I adjust my trim only once on my wireless. I put in a brand new battery and sing VERY loud very close to the pop screen, to emulate what the very worst screeming karaoke singer would sound like, and adjust the trim back until there is no distorsion. This way, almost everything else that hits this mic will not be enough to overdrive it. Remember headroom? If I have plenty of power, and I am properly running my board, I can hear a gnat breathe in this mic if I need to because I can compensate using the next control. That is the input trim on the mixer (trim pot), which I adjust while singing at a normal volume, to where it starts to clip, usually indicated by a clip LED or VU meter. I then back the trim off a tad so the clip light does not flicker. Now I am giving the mixer the maximum clean signal for that input device, whether it is a mic or mp3 player, cd player, etc. Next, I push the cannel fader for that channel to 0 VU, or on my Mackie about 3/4 of the way up. I do this for all inputs that I am using, and then lastly I push the MAINS to the desired listening volume. Note that input signals change in strength, so you may need to adjust the TRIM pot on the mixer to compensate. A timid shy girl singing a soft song will probably require you to crank up the trim so you can get your headroom back. If the next person up is Elvis, you will need to adjust the trim down some.
I hope this was not too confusing, but the A#1 rule in getting clean, clear, powerful, GREAT sound is having enough power so the power amp is only coasting! Keep in mind that the discussion on distorsion and speaker damage is contorversial, many audio engineers differ in opinion on this matter.
Having been in the audio business for over 30 years, this subject has become my pet peeve. I have taught audio mixing and sound engineering classes just because I am passionate about good sound. Nothing makes me cringe more than hearing a nice sound system sound crappy because the operator does not know how to adjust it properly.
