Speaker wattage rating. Advice Please.

[pcgorilla]

I have a pair of FXI30's that drive my surround. They have a recommended amp of 100 Watts. I am thinking of getting a bigger receiver. Maybe a 125-150 Watt.

Will I have a problem driving these speakers? I really do not want to replace them, but I do not want to "settle" for a 100 Watt amp either because I want the THX Ultra2. I generally don't blast my system. Does this matter?


I am considering a Denon 4802r.

Ay advice is appreciated.

[VR3]

No it will not hurt them. More power is better than too little. But the speakers will clip before the amp, in most cases a good amp will not clip. You shouldn't have to worry. THX should not be your deciding factor either.

[pcgorilla]

thanks. So is there a "wattage limit" I should look at for these speakers then. In other words, will a 125 wall (8ohm) be ok? What should I watch for such as playing too loud, etc?

[HBombToo]

Originally posted by Vr3MxStyler2k3

But the speakers will clip before the amp, in most cases a good amp will not clip.

can you explain speaker clipping??? this rookie is confused.

HBomb

[VR3]

Originally posted by pcgorilla
thanks. So is there a "wattage limit" I should look at for these speakers then. In other words, will a 125 wall (8ohm) be ok? What should I watch for such as playing too loud, etc?

Well let me put it this way. 60 watt amps can push 500 watt speakers. There really is no need to have 125 watts because it is THX cert. THX pretty much from what I think means ZILCH in amps. Other than that, 125 watts won't do no harm, the speaker can play at ear bleeding levels, just 125 watts is more than your speakers and you have to remember that.

Hbomb - Clipping is when it distorts.

Don't worry about it at all.

:::EX-ZACHERY!:::

[HBombToo]

Originally posted by pcgorilla
thanks. So is there a "wattage limit" I should look at for these speakers then. In other words, will a 125 wall (8ohm) be ok? What should I watch for such as playing too loud, etc?

Don't worry about it at all.

HBomb

[HBombToo]

Originally posted by Vr3MxStyler2k3


Hbomb - Clipping is when it distorts.

Yes but how do speakers clip?

[VR3]

Originally posted by HBombToo


Yes but how do speakers clip?

Hmm, when you drive them too hard and they start to sound really bad. My guess, I was talking about amps. Sorry if I missworded! Clipping is distorting, in most cases if you 'clipped' your speaker to bad, it goes snap crackle pop, and we all love that! don't we?

[HBombToo]

Originally posted by Vr3MxStyler2k3


Clipping is distorting, in most cases if you 'clipped' your speaker to bad, it goes snap crackle pop, and we all love that! don't we?

I'm trying to keep my audiophile terms straight here so:

snap crackle pop = clip which in turn = distort in a speaker.

just checken?

HBomb

[VR3]

lol! Clipping is distortion. *from what I gathered reading around here.* If I am wrong, correct me, don't toy with me! it's almost 3 am for god sakes! *Pops a cheerwine* Alright, got my caffeine!

[HBombToo]

I have been learned that passive devices cannot make active chages to the signal... does this sound correct? then i ate my teacher;)

[VR3]

Hbomb ate his teacher! Alright, a speaker will DISTORT before the amp CLIPS. Unless you have a POS amp.

[pcgorilla]

I think I got it now. Thanks so much!

nitty night!!

[HBombToo]

Originally posted by Vr3MxStyler2k3
Hbomb ate his teacher! Alright, a speaker will DISTORT before the amp CLIPS. Unless you have a POS amp.

i'm crashen

[VR3]

Originally posted by HBombToo





i'm crashen

Last night u b all kinds of tiltin, now you b crashen!

PC, glad to help ya. By the way, are you looking into seperate amps? If you are, THX dosn't do a great deal for amps (from what I think). So don't hesitate to get lower wattage if it is not THX. 1 clean watt is as good as 100 dirty ones. What brands are you looking into? But if you purchase the 125 watter, like Hbomb said, don't worry. I'm just trying to save you some money as it dosn't seem nessicary. Unless you are purchasing a 5 channel amp.....I dunno, details on what your doing?

[HBombToo]

gotta go earn a living.... good boy today was the HBomb

[VR3]

Originally posted by HBombToo
gotta go earn a living.... good boy today was the HBomb

LoL, MX is bored today he is, he organized his My Documents folder, and collected 298 emoticons and organized his emoticon folder! 2 hours MX spent doing that!

[pcgorilla]

Vr3MxStyler2k3:

I want to run a Denon 4802r. I'll have the 7600 fronts and center with 2 Fxi30's for the rear, then add 2 center backs (l/r). PSW 450 Sub. Also, a nother Zone for a seperate music source for another part of the house. Fairly Large room (20'x25').

I am piecing together the system now. Any advice?

Other info:
Mitsubishi 65411
Sony HD200 Sat Receiver

[VR3]

Originally posted by pcgorilla
Vr3MxStyler2k3:

I want to run a Denon 4802r. I'll have the 7600 fronts and center with 2 Fxi30's for the rear, then add 2 center backs (l/r). PSW 450 Sub. Also, a nother Zone for a seperate music source for another part of the house. Fairly Large room (20'x25').

I am piecing together the system now. Any advice?

Other info:
Mitsubishi 65411
Sony HD200 Sat Receiver

You have no worries man! Rock On!

[Pablo]

Sounds like it will be a rocking system. I just bought a Denon 3803 and new polks all around (listed bellow). My surrounds are rated at a max of 100 and there is no problem. The only time you may notice something is if you really crank it (and since you have a family room, you probably have a family. and with that psw450 cranking, no one else in the house will let you get it that loud).

I don't know if the THX Ultra is worth the extra cash. The specs on the amp are fairly close to the 3803 but it costs $1100 more (but you do get the fancy remote and I haven't listened to the 4802). But going the other zone could be a small problem. I believe the 3803 & 4802 both have the same functionality for the multi zone. The problem is that you need to EITHER hook up the back surrounds or the use them as zone 2 (you can't just turn off zone 2 and have 7.1). I'm going to put up a post about "speaker switches" to see what the best way to go about this would be.

Also, please let me know if I am wrong about this. I read the manual as much as I could and exprimented a bit, and still couldn't find a way to watch 7.1 surround and a CD outside at the same time.

[pcgorilla]

Right you are about the family room. I don't plan to crank it loud all the time, just when I can get away with it! I want the multi zone, but I am not to terribly concerned with having 7.1 AND Multi zone, but if me and the guys are watching football, the ladies can be in the living room or outside listening to music, or whatever.

We have a pretty large family room so I want to have the 7.1 setup, big bass to match the 65in Mitsubishi.

thanks for ytour input

[Tour2ma]

pcg,
You have a large area there... with standard 8' ceilings we're talking 4000 ft3; more if you've got a vaulted or cathedral.
Bass is your biggest challenge I would think. But if you can achieve sound levels that satisfy you, just enjoy. ;)
As for the power rating question that's already sorta been settled, remember that the speaker rating is a continuous power rating. Most speakers can handle well over their rating for short term transients. I drove a pair of Yamaha 80 w speakers with a 350/ 600 wpc Carver for years with no problems. They probably never saw over 30 w continuous, but 400+ on transients (classical music).

Sid,
In short clipping occurs when an amp runs out of power when trying to reproduce a music transient peak (wave). It usually is associated with bass reproduction. Instead of the wave signal rising, rolling over at the top and then attenuating, it plateaus at the amps power limit, goes horizontal and then "falls" off to resume the attenuation. In other words the top of the musical peak is "clipped" off.
When clipping occurs the amp creates a hypersonic "scream" on the order of 100kHz and send this signal to the speaker(s). Tweeters, being dumb, think this signal is meant to be reproduced and in trying to can burn themselves out (or "fry"). Little buggers just aren't designed to vibrate that fast. This is the reason under powering a system has more damage portential than over powering it.
I did a more detailed write somewhere here when I first started posting.

[pcgorilla]

Thanks alot for your help. I have another question, but I will probably start a new thread re: speaker wire.

pcg

[Tour2ma]

PCG,

You're welcome.

As for the wire, recommend you do a search first. It's one of the most frequent(and controversial) topics in the forum.

[byteme]

PCG, to your underpowered speakers point. Chances are, that no matter what receiver you get unless perhaps it's B&K, the quoted wattage rating will never be able to be reached by all the amps in the receiver. So you will never actually be pushing 125watts to all channels at once, the receiver just isn't capable of doing that. You would only need to be a tiny bit concerned if you added an outboard amp at some point that would overdrive the speakers.

As stated, very well by Tour2ma by the way - well done!, your biggest concern is driving the amp too hard and clipping it. Sure, you COULD blow the speaker up with too much power, but by then you and your neighbors would be deaf! I am running 125 watts from an outboard amp to all 4 of my surrounds which are a pair of f/x 500i's and a pair of RT25i's. No problems at all.

[pcgorilla]

cool. I am so glad to hear that. I have more questions about (ceiling) speakers, but I'll start a new thread. :)

[Tour2ma]

byteme,
Thanks for the kuddos, but I do have to take slight issue with your statement concerning amps not reaching their rated output. True for continuous output, but not true for transients. Also true for all channels (especially with speakers set to small), but it only takes one clipping to do the deed.
Classical is the most demanding with dynamics often in the 70 to 90 db range, by contrast rock rarely has a range of much over 20 db. Many DVD's approach the dynamic range of classical.

pcg,
Ditto my earlier search comment on your pending in-wall speaker question. Always a good idea to search first, if nothing else it can help you frame your question.
One tip is to first search only on "titles" in the section your topic should most likely be found. You'll get a more manageable number of hits.
Then, if you don't see what you need, widen the search to include "text" and all areas. Some of the best info in the past in this forum is buried in threads that have gone astray from their original topic.

[byteme]

Tour,

Absolutely agree. If I would have really gone into it I would've mentioned that for two channel you'll probably get the 125wpc - but he was talking surrounds and that in small transient bursts you'd actually be able to push more than 125 watts. You could also probably, depending on the mix - need to push the surrounds with a lot of the recievers power while the fronts were quiet so more of the amp juice would be going to the back. I think, in his case, it holds that more power the better, especially since this is a reciever which most likely won't actually drive 125wpc to all 7 channels at once. So, in reality, you're really more likely to clip a receivers amps and damage your speakers that way than you would by overpowering (especially the rears) them with 125watts or whatever the max is for a transient spike from a receiver.

[Tour2ma]

byteme,
Didn't think we were far apart and apparently we were even closer to saying the same thing than I thought. ;)

[Dr. Spec]

There are a few AVRs on the market that are rated "all channels driven simultaneously" or something to that effect.

Most multi-channel AVRs cannot make their continuous rated power into all channels at the same time. That's why each channel is rated separately in the specs sheet unless otherwise stated.

And frankly, given the dynamic nature of music, I don't that is really a big deal. There is a website floating around that actually rated AVRs on their ability to make power with all channels driven before reaching 0.1% THD and most of them checked in around 60-75% of their rated power when tested in this fashion.

FTC requires manufacturer's to rate the amps using the RMS value of the voltage peak in the continuous sine wave. That's why you often see people erroneously referring to rated power as "watts RMS" when there really is no such animal. Nevertheless, the term RMS IS integral in the calculation of the power rating for consumer amps, and technically the best way to describe a power rating would be something like "continuous watts into a given impedance load at a prescribed distortion limit as calculated with the RMS value of the voltage peak of the continuous sine wave". Of course that's a mouthful, so we solider on with "watts RMS" and continue to piss off Rooster in the process.

Anyway, I agree with Tour and bass will be your biggest challenge and you can do better than the PSW450 for clean room filling power and deep extension.

I think the either 3803 or the 4802 will have plenty of balls to run all your speaks, especially when set to Small, which presents a piece of cake load on the amp stage.

Furthermore, I don't see THX Ultra2 as being a "must have" feature/certification. I don't particularly care for the "room gain bass compensation" feature of THX Ultra 2 and honestly would consider it to be a detriment when activated. If room gain were a problem (usually its a welcome phenomenon), I'd buy a $120 BFD and fix it that way before I spent $1000 more on an AVR just because it has THX Ultra 2 certification. The DSP and DACs in the 3803 are identical to the 5803 and the 4802 has yet to see a similar upgrade, and is due for replacement in the near future. I'd go for the 3803 and buy a better sub with the difference.

Doc