Members oachs83 Posted January 14, 2015 Author Members Share Posted January 14, 2015 Would something like this amp be very helpful to me for running both mains and subs? I see it has a built in crossover as well. Or is this amp a piece of junk? http://www.sweetwater.com/store/detail/NU6000DSP Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted January 14, 2015 CMS Author Share Posted January 14, 2015 Not an amp I'd buy, but I'm partial to QSC because I've had so many years of trouble-free service from mine. Don't assume you have to buy a huge amp. The powered box mixers are notorious for overstating their amp power. The continuous rating for that Alto is probably significantly lower than what's stamped on the case. Most rack amps are pretty accurately rated. I'd go with something that will provide between 1x and 1.5x the speakers' RMS rating, and definitely not more than the program rating. There are plenty of power amps with built-in crossovers, so you shouldn't have too much trouble finding a good match. Comoxsam, to be clear I'm not poo-pooing powered mixers, but the OP's situation illustrates the tipping point for needing to go with another solution. When it's not abundantly clear what gets plugged in where, that's also time to re-think the system. I will say that with so many inexpensive good-sounding active speakers on the market, the days of powered mixers are growing shorter. It makes far more sense to have a simple system with a mixer and as many active speakers as needed. The solution is both compact and scalable, much more so than using a powered mixer with passive speakers. Link to comment Share on other sites More sharing options...
Members wesg Posted January 14, 2015 Members Share Posted January 14, 2015 The iNuke series is a pretty good bang for the buck, from what I understand. To use this amp, you're going to go mono, but that's okay. You would wire your tops in parallel with each other, and your subs in parallel with each other. Put the subs out one output of the amp, and the tops out the other. Configure the amp's crossover to send all signals from about 45Hz to about 100Hz to the sub, and from 100Hz on up to the tops. Use a 48 dB/oct Linkwitz-Riley filter. If the subs can't keep up with the mains, lower the 100Hz and raise the 45Hz. If you can configure the limiter properly, you will protect your speakers from overload while still powering them properly. I don't know how to do that, but it appears possible. Geez that's a lot of amp for $399, almost seems too good to be true. 2x3000W into 4 ohm, includes a crossover, delay, limiter, and parametric EQ. Wes Link to comment Share on other sites More sharing options...
Members Comoxsam Posted January 14, 2015 Members Share Posted January 14, 2015 Not an amp I'd buy, but I'm partial to QSC because I've had so many years of trouble-free service from mine. Don't assume you have to buy a huge amp. The powered box mixers are notorious for overstating their amp power. The continuous rating for that Alto is probably significantly lower than what's stamped on the case. Most rack amps are pretty accurately rated. I'd go with something that will provide between 1x and 1.5x the speakers' RMS rating, and definitely not more than the program rating. There are plenty of power amps with built-in crossovers, so you shouldn't have too much trouble finding a good match. Comoxsam, to be clear I'm not poo-pooing powered mixers, but the OP's situation illustrates the tipping point for needing to go with another solution. When it's not abundantly clear what gets plugged in where, that's also time to re-think the system. I will say that with so many inexpensive good-sounding active speakers on the market, the days of powered mixers are growing shorter. It makes far more sense to have a simple system with a mixer and as many active speakers as needed. The solution is both compact and scalable, much more so than using a powered mixer with passive speakers. Fully agree with everything you have said. Except maybe the part about "When it's not abundantly clear what gets plugged in where, that's also time to re-think the system." Sounds like the OP is pretty green so anything he buys is going to have a little bit of a learning curve. Let's be honest and open here regarding everything that comes with "going active". I'm currently in the process of making the switch from a powered mixer set up to a fully active one. I have purchased two new mains (Yamaha DXR's) and two used subs (Yorkville) and that has me $3100. I still have to buy a mixer. I'm looking at the $800ish (XR-18). Next comes monitors. I will need 4 or 5 and certainly don't want to buy totally cheap junk so probably looking at $400-$500 per box. That's probably in the $2000-$3000 range just for monitors. So going entirely "active" is probably going to cost me $6000-$7000. I'm already putting the brakes on and have decided to run passive monitors which I already have and they are decent. So still with the mixer I'm in for $4000. I get that active systems are considered "better" by most but the reality is that most people can't sink that kind of money into a PA system for a weekend warrior type band. These guys sound like they are just starting out and I'm sure if things go well then sinking some money into a new PA makes sense DOWN THE ROAD. At this point I don't think so. I've been in the PA buying vortex here for about a year now with all the research and decisions going into it. Everywhere you look the advice is "go active". Yes it makes perfect sense until you look at the price tag to get decent stuff. Buying inexpensive stuff just doesn't make sense IMHO if it's just for the sake of going active and not really improving your sound that much. Again I'm not arguing that powered mixers are better than active systems. I just think it's crazy that every guy who asks a simple question (about a passive set-up or powered mixer) gets told the only solution is to spend thousands and thousands of dollars. If I was in the OP's shoes I would sell the two passive Peavey subs and buy two of the active versions PV118D (I believe). They have built in crossovers and would simplify his current set up and provide at least the same level of performance he already has. (Probably much better). There are probably better subs with crossovers too that won't break the bank either. Complexity-wise we are talking two cables to the subs/crossover and two cables back to the mixer. Not rocket surgery here. The other option would be to keep the subs he has and buy a Peavey IPR (or other) amp with an internal crossover. So for $500-$1000 bucks he could be up and running with an improved set up and may NEVER need to upgrade depending how things go with the band. I think the majority of the OP's problems are set-up related. Fix those issues first and then think about spending money.... Link to comment Share on other sites More sharing options...
Members abzurd Posted January 14, 2015 Members Share Posted January 14, 2015 I read most, but not all of this thread, so if you've said this forgive me. Where are you located? Someone here may be willing and close enough to help. If not, and you live in a fairly populated area, then find some help locally. If there are some decent smaller production outfits in your area see if you can hire someone to setup and mix on your stuff. Maybe go around and listen to bands using dedicated sound guys to find someone you think might work. The result may not be the most pristine sound in the planet, but you'll be able to see what your system sounds like when it's set up to get the most out of it. If you're all open minded you can get advice on things that the band can do to improve your sound. Here's a few of those that come to mind. - Side washing amps and tilting them toward the players ear is probably the #1 cheap and easy improvement. Guitars are like laser beams. Sitting in front of an amp pointed at them head high is a brutal experience.- Going direct if possible (line out of amps pedal boards if practical) ... less open mics on stage the better- Putting only vocals in the monitors- not eqing a huge low end boost in the bass amp.... I hate that.- No drum fills on small stages- Getting right up on the mics with your mouth so you can turn the gain down thus taking some backline bleed out- If needed do to extreme bleed, setting the drums up away from the lead singer microphone. It may mean the drums off to the side- If some members only sing a few times, consider not setting up 1 microphone for 2 people. They can take turns when doing leads and "gang vocal" the harmonies if they sing at the same time... hey, this looks more rock and roll anyway. Link to comment Share on other sites More sharing options...
Members oachs83 Posted January 14, 2015 Author Members Share Posted January 14, 2015 Thanks for the tips absurd. I live in Southern Minnesota. I do own a amp stand that points the guitar amp at my head and boy did that ever make the difference. It helped out with keeping my volume lower and I am not blasting people up front. Link to comment Share on other sites More sharing options...
Members Drummer44 Posted January 15, 2015 Members Share Posted January 15, 2015 The subs are 118-SUB HC Peavey. Might be the dumbest question of the thread so far but can you daisy chain the one main to the sub below it if they have a built in crossover and run it on the C-D amp? Or is that not a good idea? You might follow up on this a bit. I don't know the answer relative to your existing sub or to other various brands of speakers... but I can tell you we can chain from our unpowered mixer to a powered sub to a powered top. The sub provides the crossover. Maybe there are some brands that will let you chain the other way, i.e., from mixer to top to sub. (Dunno.) Limitations would be about how much selectivity you might have, for selecting the crossover frequency. OTOH, if you can live with the crossover selections provided in such a system, it would eliminate a piece of gear and slightly less schlepping. FWIW, in our system, the mixer has an option to use a sub(woofer) out with built-in crossover frequency of 75Hz. Or we can use the built-in sub crossover (main out to sub to top) which happens to be 100 Hz. That doesn't give us much crossover flexibility, but it turns out 100 Hz works OK for us. Anyway, other guys here will know better about chaining possibilities... -D44 Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted January 15, 2015 CMS Author Share Posted January 15, 2015 Again I'm not arguing that powered mixers are better than active systems. I just think it's crazy that every guy who asks a simple question (about a passive set-up or powered mixer) gets told the only solution is to spend thousands and thousands of dollars. Then I guess it's a good thing that didn't happen here. I'm seeing 3 pages of people helping and making various good, and different recommendations for using the existing rig, as well as discussion of the options for expansion with various types of systems. I don't see anyone telling the OP that "the only solution" was an expensive upgrade. The OP has mentioned buying gear to make the system work, and I'm trying to make it clear that any expansion should be with an eye toward a big picture, rather than making piecemeal purchases and hoping they'll still be viable later. Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted January 15, 2015 CMS Author Share Posted January 15, 2015 The subs are 118-SUB HC Peavey. Might be the dumbest question of the thread so far but can you daisy chain the one main to the sub below it if they have a built in crossover and run it on the C-D amp? Or is that not a good idea? That would work fine if the speakers have the correct crossovers. But that's where the problem lies. For example, your PR-15 and 118 Sub HC do not have crossovers with external outputs, so there's no way to divide the signal. You can of course run the speakers full range (meaning both the sub and the PR15 will get a 20-20,000Hz signal) but that will both waste power and possibly compromise sound quality at the points where both speakers are reproducing the same frequencies (with that combination, from around 50Hz to about 250Hz) and also causes the amp to "see" lower impedance at those frequencies, which could make the problem zone louder than you want too. There aren't a lot of passive speakers with crossovers having external outputs, but it's a lot more common with active subs, and somewhat more common with active tops. One of the reasons is that passive crossover networks (meaning the crossover is dividing a speaker-level power signal rather than line-level) have to dissipate a lot of heat and may not be capable of handling a high power amplifier...and this also wastes power that should be converted to sound. Link to comment Share on other sites More sharing options...
Members oachs83 Posted January 15, 2015 Author Members Share Posted January 15, 2015 We decided we are going to go the route of an external amp to push the subs for sure. We might try to get an amp or two amps, if we get two we will run the mains and subs with the external amps. We then plan to just run monitors through the mixer amp. Getting some more specs on the amps in my mixer I found out I really have been under powering my equipment. We were not running in mono before and the real world specs are only 2 x 520 RMS and 2 x 340 RMS at 4 ohms. We were running 8 ohm speakers the mains are 400 RMS and subs 350 RMS. Talk about not knowing what in the hell we are doing. I seriously need to kick my own butt. We are looking to buy a quality amp like a QSC is Crown quality? My question is since we are now going to run MONO daisy chaining our Mains together on one amp and Then again for the subs on another what does that do for our RMS. Our speaker at 8 ohms is 400 RMS but if we daisy chain it to another it is at 4 ohms so what does that do to the RMS? Does the RMS double? Stay the same? Go up slightly? Now that I understand to run a 400w RMS speaker I should at least have a amp at 600w for that channel I want to know what size amp I should grab. Thanks again guys I have learned soooo much these last couple days. Link to comment Share on other sites More sharing options...
Members monthlymixcd Posted January 15, 2015 Members Share Posted January 15, 2015 Where I am in the Quad Cities, I'm still a little too far away from you to drop in and help you in person, but it sounds like you're using solid logic and on the right track. I wouldn't dismiss powered mains and subs as a option since you don't have an amp for your currently. Even starting with a single powered top over a single powered sub would accomplish the goal and be a good starting point for a larger scalable system. As far as buying an amp to use with your existing speakers/subs... you are correct that you should be able to just double the RMS rating and halve the impedence to arrive at the power you'd need out of each amp channel at the same impedence. As others have said before, manufacturers calculate things differently, rate component parts differently, and so it's pretty much a crap-shoot. BUT, a 1000 watts into 4 ohms amp per channel amp should be more than enough power for your tops on one channel and the subs on the other. A QSC GX7 would be a good choice... and no external crossover required since it's built in. They're 6 bills new but under $400 used. When you add up the cost of a crossover and amp... it's a bargain. Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted January 15, 2015 CMS Author Share Posted January 15, 2015 We decided we are going to go the route of an external amp to push the subs for sure. We might try to get an amp or two amps' date=' if we get two we will run the mains and subs with the external amps. We then plan to just run monitors through the mixer amp. Getting some more specs on the amps in my mixer I found out I really have been under powering my equipment. We were not running in mono before and the real world specs are only 2 x 520 RMS and 2 x 340 RMS at 4 ohms. We were running 8 ohm speakers the mains are 400 RMS and subs 350 RMS. Talk about not knowing what in the hell we are doing. I seriously need to kick my own butt. We are looking to buy a quality amp like a QSC is Crown quality? My question is since we are now going to run MONO daisy chaining our Mains together on one amp and Then again for the subs on another what does that do for our RMS. Our speaker at 8 ohms is 400 RMS but if we daisy chain it to another it is at 4 ohms so what does that do to the RMS? Does the RMS double? Stay the same? Go up slightly? Now that I understand to run a 400w RMS speaker I should at least have a amp at 600w for that channel I want to know what size amp I should grab. Thanks again guys I have learned soooo much these last couple days.[/quote'] Don't fall for the "underpower" fallacy that claims you'll blow up your speakers by using too little power. As long as you are getting enough volume without distortion, it doesn't matter what size amp you are using until it has enough power to cause damage by overexcursion of the suspension or thermal damage of the voice coil...either long-term or instantaneous. I have run a JBL rig at RMS for years, with no problems and plenty of volume. But as I think I mentioned earlier, powered mixers are somewhat notorious (with Peavey being a notable exception) for having very optimistic power ratings. One of our members is a manufacturer's engineer and he showed me some test results he had taken on well-known powered mixers...they were, in a word, pathetic. It's no big surprise...how'd we expect all that power in a chassis no larger than a passive mixer's? But the point of this is that if you were getting good volume with this rig, don't go out buy a power amp (or two) that have massive specs. You don't need that, and you could risk damaging speakers. Stick in the neighborhood of 1x to 1.5x the speaker's RMS rating. It'll be just fine. The fact that most active speakers are powered with the RMS rating of their passive counterparts should be final proof. Active speakers are covered by warranties that can't be denied by the "you used the wrong amp" excuse. Regarding impedance and power; For speakers- If you have a 100 watt 8 ohm speaker and you add a second identical speaker in parallel, the resulting set would require 200 watts into 4 ohms. For amplifiers- This is where there's a lot of gray area. For a long time amps were built such that if the RMS output rating into 8 ohms was 100 watts, the 4 ohm output was 200, and the 2 ohm rating was 400. But lately there are plenty of amps where the output can vary up OR down, as impedance loads are reduced. Some of this is due to the presence of drive processing controls that can read the amp and adjust output to provide the best longevity and performance. Link to comment Share on other sites More sharing options...
Members oachs83 Posted January 15, 2015 Author Members Share Posted January 15, 2015 Thanks a bunch Craig, I have a couple leads on a used QSC gx7 amp that if for a good price might pull the trigger on. Daisy chaining my mains at 400w RMS will put me at 800w RMS now 4 ohms. Doing the same to my subs will be at 700w total RMS 4 ohms. The gx7 states 1000w per channel at 4 ohms. Not ideal headroom but for now with cost in mind is one of the best options I have as far as I know. Not to mention a huge improvement over my current amp situation Link to comment Share on other sites More sharing options...
Members monthlymixcd Posted January 15, 2015 Members Share Posted January 15, 2015 More than enough headroom for those particular speakers, in my opinion. Really, any quality power amp from QSC, Crown, etc. at over 500W/ch at 4 ohms would be an improvement over what you've been using. Therefore, give the GX5 and maybe the Peavey IPR/IPR2 3000 amps, too. Link to comment Share on other sites More sharing options...
Members Unalaska Posted January 16, 2015 Members Share Posted January 16, 2015 I'm sorry but you don't need an external power amp. The switch on the top right labeled sub 1/sub 2 is for the subgroup! Not intended for subwoofer output. 1 decent sized power amp will do. Qsc gx7 will be fine, use the internal crossover, run ch1 subs, ch2 tops. Mono. Use the power amps inside the mixer to drive 2 monitor mixes. Ditch the crate powered mixer. Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted January 16, 2015 CMS Author Share Posted January 16, 2015 I don't like when a mixer is labeled "Sub". The term could be interpreted as "subgroup" or "subwoofer" if the user's never seen the board. I'm not thrilled either with this board's use of the term subgroup, because it's actually only a second stereo bus of the main mix, and there's no choice in what gets routed to it. They confuse the issue by mentioning that a subwoofer can be used on the "sub 1 sub 2" power amp, which could lead a user to assume that "sub" means subwoofer. Then they say that with the switch in Sub 1 + Sub 2 mode, the amp can drive a pair of stage monitors. With the main mix? While this does of course "work", wouldn't it make sense to have Aux 1 and Aux 2 routable to the amps? Link to comment Share on other sites More sharing options...
Members Drummer44 Posted January 16, 2015 Members Share Posted January 16, 2015 I'm sorry but you don't need an external power amp. 1 decent sized power amp will do. . ??? I don't like when a mixer is labeled "Sub". The term could be interpreted as "subgroup" or "subwoofer" if the user's never seen the board. I'm not thrilled either with this board's use of the term subgroup, because it's actually only a second stereo bus of the main mix, and there's no choice in what gets routed to it. They confuse the issue by mentioning that a subwoofer can be used on the "sub 1 sub 2" power amp, which could lead a user to assume that "sub" means subwoofer. Then they say that with the switch in Sub 1 + Sub 2 mode, the amp can drive a pair of stage monitors. With the main mix? While this does of course "work", wouldn't it make sense to have Aux 1 and Aux 2 routable to the amps? Agree. Our mixer uses "sub" to mostly mean sub-group... except when "sub" means sub-woofer out. At least we have some control over the two major (stereo) sub-group innies, and faders for each of the sub-group stereo pairs. Would I be right in re-capping OP's situation sorta like this: - 2x 18" passive subs, 2x 15" passive FOHs, 4x 12" passive monitors - primary Alto mixer has enough inputs - primary Alto mixer doesn't have enough outputs to provide separate monitor mixes? - secondary Crate mixer is about separate monitor mixes? ??? Somebody above (Unalaska?) suggested one coarse of action might be selling the two passive subs, replacing with actives with internal crossovers. And that would allow OP to do that daisy chain thing he asked about, so one set of outputs from the Alto would go to subs (sub-woofers), subs would send high pass to tops, and the Alto might then be able to send a couple different mixes to the monitors, no Crate required. ??? If so, perhaps it's a matter of comparing costs of active subs (minus recoup from selling the passives) against the cost of an additional power amp some have suggested? (Costs being $$ and also loading and setup convenience?) ??? Just trying to learn more here, too... -D44 Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted January 16, 2015 CMS Author Share Posted January 16, 2015 Can you explain, "you don't need an external power amp" followed by, "1 decent sized power amp will do"? I was as confused as Drummer44, but figured it might be a forum typo-can't-edit-in-tablet-app problem. Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted January 16, 2015 CMS Author Share Posted January 16, 2015 A powered speaker setup would be the way to go, and starting with the subs would be my choice. As mentioned earlier (I think) the internal amps can be used to drive the monitors by patching from Aux 1 and Aux 2 outputs with y-cables over to the Amp A-B and Amp C-D inputs. I would do this instead of using amps C and D with the internal switching to feed them Aux 1 and Aux2. My way gives him four separate amps to power 4 speakers, although he still only has 2 separate mixes. Link to comment Share on other sites More sharing options...
Members oachs83 Posted January 16, 2015 Author Members Share Posted January 16, 2015 I agree an active setup is a great way to go but cost becomes an issue. Subs starting at $500 a piece means minimum of $1k cost. A used external amp will run me about $400. Link to comment Share on other sites More sharing options...
Members WynnD Posted January 16, 2015 Members Share Posted January 16, 2015 Just a serious warning about amp ratings at different speaker impedances. Always check the manual. In most cases they are available online. My Hafler P1500 is 75 watts a channel at 8 ohms. It becomes 80 watts at 4 ohms. Prime example of how only the manual will tell you the truth about output. And the manual will also warn you when dropping the impedance too low. (You can fry an amplifier that way.) And for those who are wondering why an amp that weak would be in my stable? I use it for high frequency horns. Most of the ones I have in my bi-amp and tri-amp system don't handle more than 75 watts. (And my beloved Altec Lansings are rated 35 watts.) Link to comment Share on other sites More sharing options...
Members Drummer44 Posted January 16, 2015 Members Share Posted January 16, 2015 I agree an active setup is a great way to go but cost becomes an issue. Subs starting at $500 a piece means minimum of $1k cost. A used external amp will run me about $400. And what might you get back from selling your current passive subs? IOW, what's the net-net comparison? -D44 Link to comment Share on other sites More sharing options...
Members nchangin Posted January 17, 2015 Members Share Posted January 17, 2015 Hey I'm in SW Minnesota, probably a few counties away! Anyway, about 4 to 5 years ago I had this same issue with pv speakers and a powered board. I added a DBX crossover and separate amps for subs and tops, dumped the mixer. Makes a world of difference. With out a crossover I can't imagine how it sounds right now. Well I guess I know how it sounds without proper crossing, harsh to say the least. Careful on overpowering, those speakers don't need a tonage of juice to go boom. I came here for help as well, sure glad I did. Reading and researching pro audio is one thing but as others have pointed out the specs can and will burn you (RMS/peak power, etc) so getting first hand knowledge from the pros here is the way to go! (This next statement is personal preference only) I know amps have built in xovers etc, but most are not adjustable they are locked in say 100 Hz, which is fine and big step up from what you have but having an xover that you can adjust is key as Craig has pointed out. It's heavenly turning that frequency knob until all of sudden 4 speakers sounds like one speaker when the frequencies are directed correctly. Also takes a lot of stress off the tops because they are not reproducing those unecessary lows. and the great thing about using a cross over is you don't need an amp with dsp you can use pretty much use any amp you choose (might help your budget out) which is why I went this route, if an amp goes I just swap it out. And if you get used amps get the warranty, trust me been through a few myself buying "used". Good luck on this! Link to comment Share on other sites More sharing options...
Members oachs83 Posted January 17, 2015 Author Members Share Posted January 17, 2015 Nice to meet you nchangin, I live in Mankato. Thanks for the tips. Here is a link to our band site http://www.thewhiskeyrichardband.com/ if anyone was curious. So I found a awesome deal on a QSC GX5 amp for $175 used. Its rating is 700w at 4 ohms and 500w at 8 ohms. This seems a little light for what I have been told lately if I am going to run daisy chained two 400w mains and two 350w subs. Still is much better than what I have. Otherwise for just under $400 I found a QSC GX7 that is 1000w at 4ohms and 725w at 8ohms. Is a GX5 worth the buy or will I just be wasting money? Link to comment Share on other sites More sharing options...
Members Comoxsam Posted January 17, 2015 Members Share Posted January 17, 2015 Oach83, I think you should at least TRY your system the way Stratguru22 (and I) have suggested a few pages back. That is use a separate amp and crossover for the subs and use the mixer's amps to power your mains and monitors. Try that first before you dish out for another amp to power the mains. Despite the specs on your mixer my guess is that you will probably have more than enough power. Your mixer has the ability to run passive and active speakers so that makes it pretty versatile if you are wanting to go active in the future. You don't necessarily have to dish out big $$$ to buy all active stuff at once. I'm guessing the $175 amp isn't powerful enough. So if you are looking at spending $400-500 on an amp/crossover you really need to look at selling your current subs and use that money for buying active subs with a crossover. It might not be as expensive as you think. I think a brand new Peavey IPR2000 at the local dealer is going for $399 if you are stuck on the amp/crossover idea. Link to comment Share on other sites More sharing options...
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