Can we talk watts for a moment?

[Turdus]

I have an EV 18" sub rated as follows:

** 350 watts continuous, 700 watts program and 1,400 watts peak power handling.

Is the above saying that I should be using an amp that is between 700 and 1400 watts?

Or would it be better from 350 to 700 ?

I'm not getting what continuous, and program really mean.

[gregc]

350W RMS of clean power would be fine. The other ratings are part of the BS number game to make make things look more impressive than they are. Make sure the power rating matches the impedance of the speaker. You did not mention the '___ W into ____ ohms'. Important.

[Turdus]

Greg,

the sub is 8 ohms.

I've heard that not enough power can damage/blow speakers, and that you should supply roughly 2 times the speaker rating.... that's what I'm trying to figure out... 2 times continuous, or 2 times program.

[tomteriffic]

What this is saying is that the speaker will handle 350 watts of a broadband undistorted signal all day.

The Program rating is based on typical program material, like what your band or stereo is likely to pump through it, where it isn't full throttle 100% of the time. There's space between the notes, etc., where the speaker isn't absorbing a full amp output. Put another way, subs go "thump, thump, thump" and there's space in between those thumps where the speaker isn't taking the full brunt of the amp. If your sub is going "thuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuump", it might be an issue. Program rating is an attempt to assign a power rating based upon "real world" usage.

The Peak rating is what the speaker can absorb for very short periods of time (like a fraction of a second) pretty infrequently, without damage.

Major companies like EV are actually pretty straight-up about this stuff and include this as a good-faith attempt to give you a real world guide. Some other lesser companies, well, it might just be so much fluff.

In this case, a 700 watt (into 8 ohms) amp would be a good match. You'd have plenty of power for normal use and would be less likely to drive the amp into distortion and overheating. Odds are that that amp would also have a little headroom for extremely short bursts into the kilowatt range too.

[tbonesullivan]

the whole "underpowered blows the speakers" I believe is related to the power amp, not the speaker. You CAN blow a speaker rated at 400 watts with a 200 watt solid state power amp. If you drive it into full clipping it pretty much puts out square wave distortion, which can drive your speaker to maximum excursion, and sometimes can even make it stay on one side, which will quickly turn into a heat issue, and burn out your speaker coils.

that at least is how it was explained to me. You in general do not want your PA/whatever distorting at the power stage level.

[JohnnyB]

What TomTerrific said. It can handle continuous input of 350 watts and an average of 700 watts of typical musical signals. An ideal power amp would have around 350 to 500 watts. Given that this is an EV speaker, it may also have a rating for maximum SPL, such as 118 dB or something. You need an amp that can put out at least 350 watts cleanly to be able to hit that peak cleanly and therefore safely. And you don't want to push the speaker beyond that.

This amp should be a very good match: 200 wpc in 2-channel more or 560w x1 in mono mode. Note that the attenuators could dial down the output to 350w (in mono mode) if that made for a safer match. The sale price is killer; this is only $30 more than the 100 wpc version right now. I've heard very good things about these amps, both in build and sound quality. Get full info here.

[gorch]

I'd run the amp in the 350 to 700W region. Amps operate best up to 2/3 of the given power. So, running it at ~500W would result in the best tone to get out of it.

At parties in high school in the 80s we used to run a set of our personal Hifi amps at 20 to 30 W each, routing the signal from the mixer through tape1 in/out to connect the individual amps. Any of the amps had only one pair of speaker to drive. This solution kept the amps cold and lead to unbelievalbly cool sound. Especially, since the speakers were stacked to four towers placed to built a square or rectangle dance floor. Sorry, it just hit my mind.

[Turdus]

Recently picked up a Crown amp that, when bridged, will do 700 watts at 8 ohms. It's one of the new Class D light weight amps.

Just wanted to make sure that was actually enough power for the sub. Sounds like it will be.

[JohnnyB]

Recently picked up a Crown amp that, when bridged, will do 700 watts at 8 ohms. It's one of the new Class D light weight amps.

Just wanted to make sure that was actually enough power for the sub. Sounds like it will be.

A 700-watt Crown? Uh, yeah.

Class D should be a particularly good match. They're fast (fast rise time) and able to deliver a gob of current in an instant, exactly what a low frequency driver needs.

[Turdus]

Recently picked up a Crown amp that, when bridged, will do 700 watts at 8 ohms. It's one of the new Class D light weight amps.

Just wanted to make sure that was actually enough power for the sub. Sounds like it will be.

A 700-watt Crown? Uh, yeah.

Class D should be a particularly good match. They're fast (fast rise time) and able to deliver a gob of current in an instant, exactly what a low frequency driver needs.

whatcha saying JB? My amp is not 700 watts? LOL... that's the bridged spec. I sat in with some guys, earlier this year. They practiced through a really crappy low powered PA. The singer told me not to worry, because when they played live, he'd bring his 50,000 watt power amp.

[Thundernotes]

Pushing an amp into clipping introduces a DC component to the signal, which causes increased heating of the voice coil and can therefore burn out the speaker. It melts the insulation coating on the wire, causing the turns to short and the bubbling resin will cause the coil to rub in the magnet gap.

These Class D amps are great, and they can deliver the pulse current without clipping.

Personally, I'd go with 700 watts.

[HSB0531]

Continuous ratings (AES standard) are achieved by applying a continuous pink noise to the driver for 100 hours with a 6dB. crest factor.

A clean 350 watts @ 8 ohm amp would be the minimum I would use.

A 700w. amp @ 8 ohms would give you some headroom for peaks in the music.

1400 watts is either the thermal or mechanical limit of the speaker.

Adding a highpass filter at 30 Hz. or above will help keep the cone from overexcursion, and wasting amplifier power on subsonic frequencies.

[JohnnyB]

Recently picked up a Crown amp that, when bridged, will do 700 watts at 8 ohms. It's one of the new Class D light weight amps.

Just wanted to make sure that was actually enough power for the sub. Sounds like it will be.

A 700-watt Crown? Uh, yeah.

Class D should be a particularly good match. They're fast (fast rise time) and able to deliver a gob of current in an instant, exactly what a low frequency driver needs.

whatcha saying JB? My amp is not 700 watts? LOL... that's the bridged spec. I sat in with some guys, earlier this year. They practiced through a really crappy low powered PA. The singer told me not to worry, because when they played live, he'd bring his 50,000 watt power amp.

Is the sub a mono or dual voice coil (2-channel) model? I thought you were talking about a single 18" EV driver, so if you used a 2-channel amp, you'd be using it in bridged mode. You have an 8-ohm speaker and the Crown puts out 700 watts bridged into 8 ohms. If you use it in bridged mode, it is a 700-watt mono amp. What's with the LOL?

Besides, most 2-channel subs can be driven in mono mode. I don't know about yours; I"m not a mind-reader.

[Turdus]

What's with the LOL?

Sorry JB... when you said: "A 700-watt Crown? Uh, yeah" I read that as if you were poking fun at Crown's power rating.

I'm not sure what a dual channel sub is. This is a single 18" EV Force sub, 8 ohms. Bottom of the EV line. I'm just trying to make sure that running that amp "bridged" - 700 watts at 8 ohms is indeed enough power for the Sub's ratings I initially mentioned.

[Turdus]

Adding a highpass filter at 30 Hz. or above will help keep the cone from overexcursion, and wasting amplifier power on subsonic frequencies.

Great idea... and I am glad you mentioned it. I have a Peavey Power amp with a push button, fixed frequency low cut filter.

By setting the highpass on the Crown around 30 Hz, it does sound as if the same goal would be achieved.

[JohnnyB]

What's with the LOL?

Sorry JB... when you said: "A 700-watt Crown? Uh, yeah" I read that as if you were poking fun at Crown's power rating.

Quite the contrary. When Crown claims 700 watts into 8 ohms, you get all that and a bag of chips. Crown is famously conservative in their claims and ratings. When I said "Uh, yeah," I meant "of course it can, and a whole lot more."

I'm not sure what a dual channel sub is. This is a single 18" EV Force sub, 8 ohms. Bottom of the EV line. I'm just trying to make sure that running that amp "bridged" - 700 watts at 8 ohms is indeed enough power for the Sub's ratings I initially mentioned.

Some subs are dual channel--they have two voice coils, one to respond to the left channel and another to respond to the right. I didn't figure a pro audio sub would be 2-channel, but as I said, I didn't know for sure. Anyway, this should clear up any misgivings as to whether a Crown making 700 watts in bridged mode is up to the task: OF COURSE IT CAN!

Adding a highpass filter at 30 Hz. or above will help keep the cone from overexcursion, and wasting amplifier power on subsonic frequencies.

Great idea... and I am glad you mentioned it. I have a Peavey Power amp with a push button, fixed frequency low cut filter.

By setting the highpass on the Crown around 30 Hz, it does sound as if the same goal would be achieved.

The open B string on a 5-string bass is 30.8677 Hz. In my experience, subsonic filters start the rolloff somewhere above the stated frequency. If you do a subsonic filter, I'd recommend setting it at 20 or 25 Hz tops, or you will lose the strength of the open B string by a dB or 2. In home audio, about the only thing that can create an infrasonic signal to cause the woofers to "pump" is if the turntable's arm/cartridge match causes a resonant spike around 5-10 Hz. In live or studio performing, you might get an infrasonic signal from a passing truck or a subway train rumbling underneath. With a bass guitar or electronic keyboard, I'm not sure where the infrasonic signal would come from.