for a PA system in a barn....trying to match up the right powered mixer with speakers

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Duce Malmay

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hello -

I have 2 pairs of older model Peavey speakers & would like to connect them to a powered mixer. It will be used in a small to medium-sized barn for events, weddings etc. I will mostly need the system for a microphone and to connect an Ipod.

the 2 pairs of speakers I have:

Peavey 115 International Series III passive 3-way
800W (peak)
400W (program)
200W (cont)
8 ohms

Peavey PV 215 Dual 15" 2-way
1400W (peak)
700W (program)
4 Ohms

First of all: Can I use both pairs of speakers with one powered mixer? Or because they don't match does this prohibit this? It seems when I look at powered mixers they usually only have 2 (1 pair) of outputs.
What size/power powered mixer would I need for either speakers? We do plan to play them loud.

thank you- If there is a more appropriate place to ask this please let me know.
 
In most cases one channel of an amp could handle a single 4 ohm speaker or two 8 ohm speakers. For the most part you don't want to use multiple pairs of main speakers unless you have the right type and you know what you're doing, for acoustic rather than electrical reasons.

Get an amp with about the same power as the program rating of the speakers, or perhaps somewhat more. If the speakers don't get loud enough then you need different speakers, not more speakers.
 
OK and are the program ratings done as a pair? as in a 700W amp would be OK with the Peavey PV 215 700W pair? or 1400W amp with the 2015 700W pair?
 
For what it's worth I just did a gig in a smallish hall (maybe 300 seated + some dance room) with a Carvin powered mixer (4 -400 watt amps) and four of likely these- or similar;
PM153 Molded 3-Way 15 Inch Speaker – Carvin Audio
"96dB sensitivity listed.
Guitars bass drums and some keys, at modest blues/pop levels.
Two for front of house, two for monitors. - We were indicating lite clipping on the amps- with Just vocals in the pa.

Just a heads up on 'available head room/power on powered mixers.

To be fair even though the clip' leds were lighting on some peaks, I never heard any hint of distortion. So maybe Carvin builds in a bit spare in there.
 
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mixsit said:
"96dB sensitivity listed.
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That seems low. My last pair of PA speakers (Peavey Impulse 200 4 ohm) had a sensitivity of 101dB. If the OP could get the sensitivity ratings of his two kinds of speakers it would say something about how loud they get on a given amount of power.
 
I would ditch the powered mixer idea and go with a small non powered mixer and 2 power amps, you only need a few inputs so a 4 channel mixer would work, and they are fairly cheap. on the power amps pay attention to the rating and lowest ohm load the amp will handle, for instance a 1000 watt power amp that will go down to a 4 ohm load is usually what the output is advertised at, if you connect a 8 ohm load you will only get about half of that. also, go a little above the rated program load on the speakers, say you have a 500 watt program rated speaker, you use a amp rated a 500 watts max, then the amp will be running at it peak output all the time, if you go with a 750 watt amp, then you are not pushing the amp to the limit, it will run cooler and last longer. :D
 
I'm all for ditching the box mixer, but I would first look at the sensitivity and/or max SPL ratings of the given speakers so one can estimate the SPL they'll make for a given amount of power. How loud is loud? Over 100dBSPL A weighted is pretty loud, 110 is approaching stupid and 120 is definitely stupid loud.

If you start with 123.5dBSPL at 1 meter (the PV 215's max rating) and double the distance a few times out to 8 meters you're down 18dB to 105.3dB, which is quite loud. If max SPL really means maximum then that's at the full 1400 watts. If you truly need loud then you're going to need an amp that can make that 1400 watts without working too hard.

There's a good argument for running 1.5 to 2x the speaker's rated power, but I think that needs skilled attention, something you might not have time for if you're mixing your own band.
 
You can upgrade or repair or replace an amp. Throwing an entire mixer amp away is the only solution if you discover it's too quiet. Combining them is handy for moving it about, but amps die, and if you don't need to combine, don't.

The Peavey boxes are basic and pretty tough. They don't sound the best, but many like them. The 2 X 15" box already has its drivers in parallel, so adding the other brings the impedance down below 3 Ohms. Can your amp handle it? Many can with the level low, but turn the volume up and they have a lot of heat to shift. There is another problem. Different speakers with different sensitivities mean the available volume is shared unevenly. One cab will be louder than the other type. The volume mismatch means it will be working harder, and Peaveys sound rough run hard, and have a habit of popping the internal lightbulb they use to protect the HF driver. Peaveys are tough and hardwearing. They also get waffly at the bottom, hence why they get matched with a sub if you want some oomph at the bottom end. If you turn up the bass you find a huge hole in the middle where the crossover diverts to the horn. They will sound like typical wedding speakers. All thud and presence and painful at the top when the volume goes up.
 
One thing I forgot to mention, related to Rob's points about volume. If you're running your speakers right up to their limits they're not going to sound their best. Speakers go into "power compression" when they are near their maximum volume which affects the sound and makes it easy to push them too hard. If you need just a little more volume but you're already in power compression it's tempting to push a little more gain, but the volume won't increase much so you push a little more and so on until the voice coil overheats or the mechanical damage occurs. Ideally if you need to get 120dBSPL out of a speaker get a speaker that can do 132dBSPL. Stay well out of power compression and your speakers will sound better and last longer.
 
So glad the sensitivity point came up early! You cannot compare the loudness of speakers unless you know this. But then there is a tolerance, often + or - 2dB and (be it whispered) mnfctrs HAVE been known to tell porkies!

Personally I would buy another PA and run both sets of speakers. Note, the speakers need to be "stacked" (shut up at the back boy!) one atop the other and the top one in each case upside down so the tweeters are as close together as possible. This might involve some creative use of a barrel and scaff clamps. MAKE IT SAFE!

And no, don't run the system flat out, sounds nasty. Start the night at a modest level, you will be asked to turn up as the room fills and people tend to get deafer as they get pissder. Always worth buying a modest SPL meter $20 will get you something adequate.

BTW "barn" sound like an acoustic nightmare! If it is on a farm see of you can stack some materials around the walls, especially the rear wall. Straw bales are ideal but even sacks of feed or fertilizer will help absorb some sound. If it has a curved iron roof that could be MOST interesting!

Dave.
 
I would resort to the stacked thing if I had to and I had four matched speakers. I wouldn't do it with two different pairs. Well, maybe one pair on the left and the other pair on the right, but that violates my preference for symmetry.
 
bouldersoundguy said:
I would resort to the stacked thing if I had to and I had four matched speakers. I wouldn't do it with two different pairs. Well, maybe one pair on the left and the other pair on the right, but that violates my preference for symmetry.
Click to expand...

Come on BSG! We are talking Party PA and old, hammer and chisel Peaveys not Quad statics! At ten feet plus and beyond they will "integrate" beautifully!

I just reckon the OP can use what he has to make the cleanest, high level noise he can.

Dave. (BTW I DO mean a 4 Ohm atop an 8 Ohm or V-V? Matched side for side)
 
Hmmm...assuming you want bass heavy rock/dance type stuff...

If you have a way of doing a rough crossover (even a mixer with one channel EQ'd to be only bass) maybe use the 215's (with their 15 inch bass drivers) as subs and the 115s as full range.
 
Bobbsy said:
Hmmm...assuming you want bass heavy rock/dance type stuff...

If you have a way of doing a rough crossover (even a mixer with one channel EQ'd to be only bass) maybe use the 215's (with their 15 inch bass drivers) as subs and the 115s as full range.
Click to expand...

Yeah, I'd rather do this than the stack. Actually, I used to do a hybrid of the two, a pair of Yamaha S4115H on the floor angled in and a pair of pole mount speakers shooting back over the audience. The Yamaha speakers filled in the dance floor and the lows while the pole mount speakers did mid-highs to the rest of the room. I didn't even use a crossover, but I put each pair on its own amp. Since the speakers' coverage patterns didn't overlap much it worked well.
 
bouldersoundguy said:
Yeah, I'd rather do this than the stack. Actually, I used to do a hybrid of the two, a pair of Yamaha S4115H on the floor angled in and a pair of pole mount speakers shooting back over the audience. The Yamaha speakers filled in the dance floor and the lows while the pole mount speakers did mid-highs to the rest of the room. I didn't even use a crossover, but I put each pair on its own amp. Since the speakers' coverage patterns didn't overlap much it worked well.
Click to expand...

Yes,...Way! It is just that the bigger the source gets the more efficient it becomes out front and OP seems to want loud!

Dave.
 
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