EV QRX 218 Subs

[MainEventSound]

I just bought my first pair of real subs today for my show this Saturday. They should sound great. I've got a QSC 3602 in bridged on each sub. I'll let everyone know how they work out.

[Mogwix]

Nice! I love these subs!

[Craig Vecchione]

Why don't you explain to the OP how to set those limiters, Matt?

[Square]

I will fill in until AgedHorse gets here.

 

I have 8 of the 218's (and 8 of the QRx153 tops), and you really should be careful with them at that power level. I drive 2 boxes off of one channel of a QSC 6.0II, which gives each box about 1500 watts - less than half of what you are about to do. I have not lost any drivers, and they still outrun my top boxes in terms of output (though my tops are more of a "high fidelity" box than a "high output" box).

 

 

Your 3602 will do 1100 per channel @ 4 ohms. You may find that to be sufficient for your subs, and you could free up an amp.

 

I have been very pleased with my boxes (tops and bottoms) and I usually end up appreciating them more when I get a chance to hear other rigs. I think you will be happy with your purchase, but do be careful with the power.

[agedhorse]

I have reconed so many of the EVX series drivers for customers (warranty denied) powered that way that you should be aware that the cost is significant and EV is not as liberal as Yorkville when it comes to "no fault".

 

The EVX is a great driver but does not handle abuse all that well. 600 watts is just about right for that driver IME.

 

Matt is a very special guy, IMO he's cocky with his bold advice to other people suggesting they overpowering their speakers but I'll bet that if you damage yout speakers from following his advice and then discover that his advice is not very good, he won't step up to the plate and help you out on your repairs either.

 

Advice is cheap, generally the worse the information the cheaper it is. The challange is to determine which cheap advice is good and which is not all at that good. Personally, I wouldn't take the advice from somebody who doesn't understand in detail how to CORRECTLY set limiters, and who doesn't understand the dynamics of speaker failure.

 

So Matt, as Craig suggested, how do you set a limiter correctly? Please explain how a dual time constant, multislope limiter would be used to achieve better driver protection (this is pretty much how the big boys who power their speakers to their limits keep from destroying things with regularity). Don and I have touched on this in the past, it's done in many of the powered speaker products too.

[MrJoshua]

Well I don't know, I don't run any limiters on my system. out of the board, into an analog black box crossover into the amps. No cliping of the amps.. not distortion of the speakers... I beleive EV gives you settings for the subs on their sit to use.

 

Jeez. I'd hate to be your system when the keyboard player spills his beer on his rig and sends a nice jolt through the DI to your mixer. Limiters are like any other protective device - you don't need 'em until you NEED them, and then you're VERY glad you had them.

 

MainEventSound, if I were you, I'd try running one sub off each side of the amp first. I'd be very surprised if that wasn't sufficient. And if it isn't, I'd look at picking up more subs.

[Craig Vecchione]

 

Well I don't know, I don't run any limiters on my system. out of the board, into an analog black box crossover into the amps. No cliping of the amps.. not distortion of the speakers... I beleive EV gives you settings for the subs on their sit to use.

 

 

I didn't ask what you do with your system. I'm suggesting that before you recommend putting 3400 watts into a 1200 watt sub with the offhand comment to "set the limiters", that you explain to the OP how to do so.

[drumstix]

Oh my, where is agedhorse and craigv to tell you that you

[Norton666]

That is WAY too much power for those boxes IMO. I would run both boxes off of one 3602 stereo if it were my rig. There is a local guy who runs a full QRX rig and he bridges a PL 4.0 into each sub and every time we work together it scares the living {censored} out of me to do anything on his rig. He also says every few months he spends $500 a box to get the drivers reconed , but its worth it because they dont sound good until you really feed em some power. Doesnt make a damn bit of sense to me. They are AWESOME sounding subs though. It seems the world over that EV= "need way more power than they are rated for"

[Craig Vecchione]

 

That is WAY too much power for those boxes IMO. I would run both boxes off of one 3602 stereo if it were my rig. There is a local guy who runs a full QRX rig and he bridges a PL 4.0 into each sub and every time we work together it scares the living {censored} out of me to do anything on his rig. He also says every few months he spends $500 a box to get the drivers reconed , but its worth it because they dont sound good until you really feed em some power. Doesnt make a damn bit of sense to me. They are AWESOME sounding subs though. It seems the world over that EV= "need way more power than they are rated for"

 

 

Actually, EV are pretty accurately rated for power, and as you're seeing with that guy's quarterly reconing budget, they don't like being overpowered. He's pretty silly....he could simply get more subs and have the sound and no need to recone...all for what he's probably already spent on new cones.

[MainEventSound]

It's not a 1200 watt sub, it's a 2400 watt sub. RMS: 1200 Program: 2400 Peak: 4800 I've always matched up to program to get "overhead" and NEVER blown anything at all.

[Craig Vecchione]

 

It's not a 1200 watt sub, it's a 2400 watt sub. RMS: 1200 Program: 2400 Peak: 4800 I've always matched up to program to get "overhead" and NEVER blown anything at all.

 

 

Everyone who's posted here knows the power ratings. You can call it whatever you want. How is 3600 watts "matched up to program" when the program rating is 2400 watts?

 

It's great that you've NEVER blown anything at all. The goal is to continue that, not to argue. You can put any amp you want on the speaker if you've got appropriate limiting to keep that amp from destroying the speaker.

 

You've used this speaker exactly zero times, and you've received advice from several guys who have used them extensively, and one guy who makes part of his living reconing them. Is there any possibility they may know something you don't, and that it might be a good idea to at least consider their advice?

 

Honestly, I don't understand the contentious attitude returned to people who make an effort to help others.

[boomerweps]

 

Why don't you explain to the OP how to set those limiters, Matt?

 

 

Craig (and agehorse),

 

These unsolicited and unwarranted remarks in this thread are beneath you. Please refrain from this while I still have great respect for you and your experience.

 

Boomerweps

[Craig Vecchione]

 

Craig (and agehorse), These unsolicited and unwarranted remarks in this thread are beneath you. Please refrain from this while I still have great respect for you and your experience. Boomerweps

 

 

Is today the first you've read this thread? I can explain further based upon your answer.

[boomerweps]

 

Is today the first you've read this thread? I can explain further based upon your answer.

 

 

 

Apparently, yes. Were those quotes from Matt removed from the thread?

 

Boomerweps

[Craig Vecchione]

 

Apparently, yes. Were those quotes from Matt removed from the thread? Boomerweps

 

 

I'll explain. Matt replied to the OP advising him to go ahead with the powering scheme of 3600 watts into one QRX, to just use his limiters, set the crossover and go on. He prefaced this with an offhand remark to the effect of, "Hey, where's Craigv and agedhorse telling you that this is too much power?". He followed it with to the effect that EV had the settings somehere in their literature.

 

My reponse urging him to explain how to set those limiters was returned with him replying that he had no idea how to do that, because he didn't use any limiting in his system.

 

Last night around 7pm he changed his signature, urging everyone here to go to Prosoundweb. He replaced the content of roughly 400 of his posts to several rants, mostly these two:

 

If you want the true answer, go to Pro Sound Web.

 

If you would like professional advice from the pros, go to PSW, which is the home of professionals in Live Sound.

 

So if you want to hang out with a professional crowd head over to PSW.

 

AND:

 

Call me cocky it doesn

[agedhorse]

 

It's not a 1200 watt sub, it's a 2400 watt sub. RMS: 1200 Program: 2400 Peak: 4800 I've always matched up to program to get "overhead" and NEVER blown anything at all.

 

 

Yeah, that's what my customers thought before they damaged their's too.

 

It's a 1200 watt RMS box, the drivers are 600 watts RMS and they do not do well powered much beyond this. BUT, that's the tradeoff they made to achieve pretty darned good performance in the LF bandwidth and distortion parameters.

 

Most of this limited power handling is due to mechanical limitations that appear (though not positive) to be due to the field focusing and extension of the magnetic gap along with the length of the bobbin below the cone neck. It's a pretty well known issue but frankly it's no big deal if you power things reasonably. Another proble4m I have seen is a failutre of the surround where it transitions to the edge of the cone. It fails from fatigue when driven very hard over a long period of time.

 

You could power them at program power, but in the event of a lapse of good judgement (or an accident) you don't have as much latitude before damage occurs. The benefit of a more reasonable powering scheme is that this variable rapidly becomes a non-issue.

[MainEventSound]

I don't mean any disrespect at all gentlemen. I do appreciate everything that comes back to me. Agedhorse, so basically, I could put a 218 on each side of a qsc plx 3602 correct??

[guitarharv52]

 

I don't mean any disrespect at all gentlemen. I do appreciate everything that comes back to me. Agedhorse, so basically, I could put a 218 on each side of a qsc plx 3602 correct??

 

 

I bet it will sound great.What tops are you using over your subs?I imagine the 212 over those subs would make a killer system.

As for the topic of massive power to speakers, I have browsed the other forum mentioned just to hear the other side of the argument.After a few threads emerged a pattern of high power then speaker recone.Hmmm

 

"pros" that destroy equipment on a regular basis at great expense or

 

People who either design,repair.or engineer equipment safely for years.One point stressed here is to look at how the companies power their own speakers.

 

Good Luck!

[Norton666]

 

I don't mean any disrespect at all gentlemen. I do appreciate everything that comes back to me. Agedhorse, so basically, I could put a 218 on each side of a qsc plx 3602 correct??

 

 

That would be an ideal and very safe setup IMO.

[agedhorse]

 

I don't mean any disrespect at all gentlemen. I do appreciate everything that comes back to me. Agedhorse, so basically, I could put a 218 on each side of a qsc plx 3602 correct??

 

 

Should be excellent. Limiters on, HPF at 30Hz and you are good to go for a long time.

[Craig Vecchione]

 

I don't mean any disrespect at all gentlemen. I do appreciate everything that comes back to me. Agedhorse, so basically, I could put a 218 on each side of a qsc plx 3602 correct??

 

 

I've been using a very similar setup...SR4719X powered by one PLX3402...for years. Works great.

[kennyp]

I've been using these subs for about eight years averaging probably 8 weekend gigs per month in various applications, with a fairly loud band. I'm using a QSC RMX5050 power amp which puts out 1800 watts per side @ 4 ohms. I read the following on QSC's website:

 

To get the best sonic performance from your loudspeakers, QSC recommends that you power them with an amplifier that is rated for at least two times the loudspeaker's continuous power rating or equal to the loudspeaker's program power rating.

 

I'm a little confused because if I follow this standard the RMX 5050 is actually under-powered because twice the continuous rating is 2400 watts, yet am I correct that the advice I am reading on here is to use less power? I have had to recone two drivers over the past 8 years and they were covered by my warranty. The speaker reconing professional that I dealt with explained to me that typical speaker failure is usually due to clipping an amplifier in to distortion as that is what will fry the voice coil. As further info I am using limiter in a DBX Driverack PA to set the limiter to the subs but I'm not positive it is set correctly. Any thoughts, advice etc., are welcome.

[agedhorse]

QSC and all amp manufacturers want to sell as much amp as they can stuff down your throat. That's where the money is when selling amps.

 

With sub failures, your speaker professional appears to be anything but professional or experienced (sadly). By far and away the most common cause of driver failure in subs is mechanical damage caused by too much power, and it's made worse by improper high pass filter configuration and a lack of good common sense. I have been reconing for 30 years, and have spent a lot of time as a (real) engineer studying failure modes in loudspeakers since it's a big part of my day job designing such products, especially important with powered speakers.

 

IF, you use proper high pass filtering (properly set for the enclosure as a system), always have enough PA for the job at hand, and have your limiting set so that you are limiting your mechanical excursions to 2x the RMS level but at the same time limiting the longer term power (say anything over 250-500mSec for a sub) to approx. the RMS rating, you will be getting the most performance out of the box possible with reasonable expectations for reliability.

 

If you do not always have enough PA for the job, do not have the proper HPF's, do not have good judgement or the rig is run by those who may not share your care of the equipment then I usually recommend limiting the mechanical point back to between the RMS and 1.5x the RMS value.

 

Setting limiter points takes some advanced knowledge and generally some test equipment, though there are some fast and dirty methods that can be accurate provided you do not make poor assumptions.

 

You must also insure that you have adequate headroom to allow the limiting functions to work properly. Do NOT follow the DBX tech note on the back page of the manual, that info is just wrong and while it maximizes signal to noise ratio it effectively eliminates the proper operation of the limiting function everywhere else in the signal chain (DR and amps). This allows the drive electronics (mixer and possible the DR itself) to clip at or before the limiters engage which defeats the entire limiter strategy. I recommend a MINIMUM of 6dB of headroom (I generally program between 10 & 12dB into client's gain structure) between the point that rated output (clip/limit point) is reached on the amps and before the mixer/drive electronics clip.

[kennyp]

Wow! Good info. We've had pretty good luck so far but I'm sure checking out some of this advice can yield better optimization, sound, and reliability of our speaker system. I didn't mention but I'm also using the QRX 212 75's for the tops. Nice system but even after eight years of steady use we've still got some homework to do. Thanks.