#1
I desperately need help here!!!! So here is the scoop. i burnt out one of my PA speakers today and need to replace it. I figured I could do the easy thing and just get a new speaker that matches the diameter and ohms and wattage, but there is a reason I burnt it out. I pushed my amp too hard into it and they werent exactly a perfect match. bummer. so i have a Crown X2000 power amp that puts out 450 Watts per channel at 4 Ohms and 330 Watts per channel at 8 Ohms. I already have the Speaker cabinet and horns so i figured rather than buy 2 whole new PA speakers, maybe i should just replace the main sub speakers to match my amp better. currently they are 8 ohms that run at 600 watts and are 15 inches. I have the x2000 bridged so it runs them at 900 watts in mono which i knew was high, but has been fine for a long time as long as i kept the volume low ish. so how do i go about doing this? should i buy something like a set of speakers that are 15 inch, run at 8 ohms at 400 watts and run them in stereo again rather than bridged, or should i get something like 2 450 watt speakers and bridge them? I don't really know how to do this. like i said, there are horns that don't have an sort of description on them as to what their specs are. they don't have a coil really. its like a plastic housing with 2 wires running across a flat piece of metal about the size of a quarter that is glued to a speaker cone. I doubt they are consuming much wattage but i have no idea. help! I'll offer more information if needed, but this is hopefully enough. THANK YOU SO MUCH
Peavey 6505+ head
Mesa 4x12 Rectifier Cab
Line 6 Spider III 30 Watt (practice amp)
Schecter Hellraiser C-7
Schecter Hellraiser C-1 FR
Boss NS-2 noise suppressor
MXR 10 Band EQ KFK
Boss DD-7 Delay
#2
Unlike guitar speakers, PA speakers are often specific to the cabinet and the task. IOW, simply buying a random 15" speaker probably won't be the best idea. You're best served buying the replacement speaker from the company that made the PA system *unless* you know exactly what the replacement would be (brand, design, etc.). If you have a 15" speaker that's designed for a specific cabinet volume and for specific frequencies at a specific power rating, you're going to want that speaker back.

Most solid state stereo power amps produce one power rating per side at 8 ohms (speaker cabinet impedance), another at 4 ohms, and something completely different when bridged, mono, at a specific impedance. Usually maximum power is produced with the outputs bridged, mono, at the lowest impedance at which the amp is stable.

More important, you need to know how the speakers are achieving their ratings. If you're trying to match a set of speakers rated at 450W peak to an amplifier that puts out 450W RMS, you're going to have a mismatch in actual power of 2x or even 4X. You didn't mention the brand or model of the speaker cabinets you own, or we could (hopefully) look them up and see what you've got. Speaker manufacturers often inflate their ratings as part of a half-fast marketing strategy, particularly where low end speakers are concerned.
#3
okay yeah I know most of what you're saying. And honestly the speaker cabinets I have don't have a brand to them at all. Is quite strange. I have already taken the main speaker out of the cabinet and there's no fancy wiring or circuit boards or anything in there. It's basically just to quarter inch holes for the speaker cables to go into, and a couple of wires that lead to the sub and a couple of wires that lead to the horn. It's an extremely simply built cabinet. I understand that peak wattage doesn't mean anything. I have found some speakers that run at the same RMS as my amp. I'm basically just wondering if that is how it would work in this situation. I'm not at home at the moment but I seem to recall the sub speaker being like zebra brand or something weird like that. The horn doesn't have any indication of who made it. I hope that offers a little more information.
Peavey 6505+ head
Mesa 4x12 Rectifier Cab
Line 6 Spider III 30 Watt (practice amp)
Schecter Hellraiser C-7
Schecter Hellraiser C-1 FR
Boss NS-2 noise suppressor
MXR 10 Band EQ KFK
Boss DD-7 Delay
#4
go to this site and call or Email them (I buy almost all of my replacement parts from them and they ship insanely quick) Tell him Rob from Fl sent you and he'll either give you a break or free shipping
www.soundspeakerrepair.com
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate
#5
Maybe, just maybe...

Now is the time to get some active (biamp powered) speakers with built in limiters and speaker protection so you don't blow stuff up. Great sound every night with no muss, no fuss, no math involved, and no smoke coming out of the baffle ports. EV, JBL, Mackie, QSC, and Carvin all make good quality stuff that will make loud music long time.
"Your sound is in your hands as much as anything. It's the way you pick, and the way you hold the guitar, more than it is the amp or the guitar you use." -- Stevie Ray Vaughan

"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

Guthrie on tone: https://www.youtube.com/watch?v=zmohdG9lLqY
#6
ok cool I will check that site out. But can anybody confirm what I'm planning on doing will work? Should I just get a set of speakers that match the RMS output of my amp?
Peavey 6505+ head
Mesa 4x12 Rectifier Cab
Line 6 Spider III 30 Watt (practice amp)
Schecter Hellraiser C-7
Schecter Hellraiser C-1 FR
Boss NS-2 noise suppressor
MXR 10 Band EQ KFK
Boss DD-7 Delay
Last edited by seankir92 at Jan 27, 2015,
#7
also this setup is for band practice vocals, so it's not like I'm DJing or anything with these
Peavey 6505+ head
Mesa 4x12 Rectifier Cab
Line 6 Spider III 30 Watt (practice amp)
Schecter Hellraiser C-7
Schecter Hellraiser C-1 FR
Boss NS-2 noise suppressor
MXR 10 Band EQ KFK
Boss DD-7 Delay
Last edited by seankir92 at Jan 27, 2015,
#8
OK if what you say about the speaker is true then there is no crossover in the cab. Unless they are a bad self build job then this means the horns are piezo horns, and the maximum power handling is 100W. Power handling of the bass units is probably not 600W. Almost all 15's have 3" voice coils and will only dissipate 300W, long before they get to this most low cost speakers run out of excursion so should be de-rated to less than this. There are lots of misleading claims about power ratings made by manufacturers sadly.

Without them here in front of me I can't be sure but these probably aren't worth thinking about repairing, you could probably buy some better quality used speakers for less than the repair cost. If it is just the piezo horns gone then these only cost a couple of dollars to replace but the quality will never be great. There's no doubt that a pair of active PA speakers would serve you well but expect to pay £700 (c$1000) for anything decent. Since you have an amp get some used passive PA speakers from one of the better brands mentioned, They should handle 350W from your amp if you buy 8ohm speakers, which most of them are.
#9
Hmmm, time to find some real speakers. Passive or active doesn't matter to me but active speakers usually survive abuse better. I often see Yamaha club series and JBL Eon 15s in CL for $400/pr. I would sell the Crown amp and get the Eons. If you want to stay with passive spkrs, avoid bridging the amp unless you need all that power to drive a 18" sub. Amps run much cooler when not in bridge mode.
"Your sound is in your hands as much as anything. It's the way you pick, and the way you hold the guitar, more than it is the amp or the guitar you use." -- Stevie Ray Vaughan

"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

Guthrie on tone: https://www.youtube.com/watch?v=zmohdG9lLqY
#10
Quote by Phil Starr
OK if what you say about the speaker is true then there is no crossover in the cab. Unless they are a bad self build job then this means the horns are piezo horns, and the maximum power handling is 100W. Power handling of the bass units is probably not 600W. Almost all 15's have 3" voice coils and will only dissipate 300W, long before they get to this most low cost speakers run out of excursion so should be de-rated to less than this. There are lots of misleading claims about power ratings made by manufacturers sadly.


Good points all. I do have a pair of speakers that carry two each 1165 piezo tweeters (supposed to handle 400W apiece from 1800Hz to about 20Khz), but you're not generally going to find piezos on the high-end cabinets.

As you say, most 15s don't have great power handling (or excursion). You have to get into a much better grade of speaker AND you need to have a crossover involved. I've got four cabinets with Eminence Kappalite (neo-based) 3015LF drivers for the low end. I've run single cabs with up to 900W routinely (8 ohms), but they're running 18Sound 6.5" mids drivers and good tweeters.
#11
I would like to be able to afford nice things but I can't haha. Like I said I don't need them to be crazy nice. It's just for band practice. I'd rather not sell my amp but if I have to then I guess I could. What about these? I've heard "rule of thumb is amp should be 50 percent more powerful than the speakers." I don't really know if that's true but would 2 of these work with my crown x2000? http://www.musiciansfriend.com/pro-audio/kustom-pa-kpc215h-2x15-pa-speaker-cabinet-with-horn
Peavey 6505+ head
Mesa 4x12 Rectifier Cab
Line 6 Spider III 30 Watt (practice amp)
Schecter Hellraiser C-7
Schecter Hellraiser C-1 FR
Boss NS-2 noise suppressor
MXR 10 Band EQ KFK
Boss DD-7 Delay
#12
Quote by seankir92
I would like to be able to afford nice things but I can't haha. Like I said I don't need them to be crazy nice. It's just for band practice. I'd rather not sell my amp but if I have to then I guess I could. What about these? I've heard "rule of thumb is amp should be 50 percent more powerful than the speakers." I don't really know if that's true but would 2 of these work with my crown x2000? http://www.musiciansfriend.com/pro-audio/kustom-pa-kpc215h-2x15-pa-speaker-cabinet-with-horn


Big, heavy, cheap, and not very loud. They will work with your amp if you pay attention to levels and don't clip the snot out of them.

These are lighter, louder, sound way better and you can find them used often for $300/pr.
http://providence.craigslist.org/msg/4833883895.html

These are lighter, louder, sound WAY better and have their own internal biamp so the Crown can take a rest. https://reverb.com/item/269633-jbl-eon-15p-gray-pair?_aid=pla&pla=1&gclid=CNzbobewt8MCFVJcfgodQ2cAcQ
"Your sound is in your hands as much as anything. It's the way you pick, and the way you hold the guitar, more than it is the amp or the guitar you use." -- Stevie Ray Vaughan

"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

Guthrie on tone: https://www.youtube.com/watch?v=zmohdG9lLqY
Last edited by Cajundaddy at Jan 28, 2015,
#13
Take a look at the Carvin LS 1503 cabs. Around $279 each but they're three-way (15" LF driver) and capable of handling around 800W each.

Or spend the same amount and get the PM12A's with a single 12" speaker and tweeter each (NON piezo) and 400W RMS amplification built in.