Is this what clipping sounds like? (1 Viewer)

[James~P]

i notice that high-hat hits, or the syillable "S" come out very sharply+harsly at higher volumes... whereas a few notches down (almost as loud) they dont do that... is this a fault of an amp being driven too hard, or is it the speakers? i noticed the same thing with two sets of speakers with similiar effencies around the same volume levels..



its a Maranetz SR4200 with 75x5 watts per channel.


if this is infact clipping, could you suggest to me a good budget poweramp for 5 channels? (as cheap as possible...)

 

[TomCW]

Could be clipping. How (in)efficient are your speakers? If your Marantz is actually putting out 75W, then adding a power amp of 150W won't really be very much louder (3dB).
Higher efficiency speakers may be more cost effective in the long run.

Tom

 

[James~P]

i dont want it to be louder, that volume was louder than i'd usually listen.



how much money for a two channel 150x2 amp?

 

[Jason.Soko]

Unfortunately, the Marantz's put out nothing for power. The SR7200, rated for 105x6 puts out in reality 27x6.

http://www.geocities.com/Area51/Holl...1/ratevsac.htm

 

[James~P]

so would a poweramp cause an improvment? i like the reciever quite a bit, i'd rather not ditch it.

 

[David Judah]

When it starts to sound thin and compressed, it usually means you are reaching your amp's limits. It's a common problem with receivers, since most of them don't have robust power supplies to begin with.

Adding an amp can work wonders, especially for giving you a little more room for those dynamic peaks. Manufacturer's wattage ratings don't always give you the whole picture, so I think you could benefit from outboard amplification even at 125 Wpc or so.

There are alot of good brands out there, so search the net and you should be able to find a good stereo amp for a reasonable price. Companies like Adcom, Rotel, and NAD(among others)make good amps, so you might check some of them out. There's alot of used bargains out there, as well. You might want to check the For Sale Forum here or a place like audiogon.com.

Good luck,

DJ

 

[Tim Streagle]

Clipping is generally noticed in conjunction with heavy bass passages. High frequency waves typically don't exhibit distortion due to clipping unless grossly overdriven. It's when a demanding low frequency passage is combined with high frequency content; that is when you will notice the highs distort.

Amplifiers go through other, more subtle effects on sound waves before they clip signals audibly. Usually I hear a considerable loss of dynamic headroom first, then the music begins to sound somewhat compressed. However if the high freqency drivers are biamped with low powered amplifiers, then you may be experiencing the distortion attributed to clipping.

I have planar speakers that are very inefficient. With 300 watts rms driving them I can still tell when they are reaching the point when transients have less impact and things start to sound mushy. This is usually before I have noticed the peak LED's are red-lining. My ears often prove to be more sensitive than the meters!

When I ran pro sound systems for large bands I would often notice high frequency breakup before the clipping indicators on the amps would light up. This would generally be long after the low end cabinets were overstressed. However low freq. distortion is much less objectionable to most listeners... especially when they've had too much to drink!

 

[ChrisLazarko]

I have a Harman/Kardon AVR-225 reciever and it is something like 55w x5 channels. Now I have heard Harman rates there amps very well and it is also high current and discrete as well. I currently own the Klipsch Quintet speakers and have been thinking of any upgrade. I know Klipsch is a very efficient speaker but I am wondering if with a bigger speaker as for example a Klipsch RF-7 if there would end up being a problem with it?

Thanks.

 

[DanielSmi]

It could very likely be your room that's causing the problem. Your room makes up the sound if your room sounds bad then the music sounds bad expecially at higher volumes. I used to have a similiar problem that when playing at loud volumes the treble would get really loud and hurt my ears. This problem went away when I added some acoustic absorbers and now this problem is greatly reduced almost non existent (I'm not done adding absorbers yet just started) and my music sounds much much better at louder volumes.

Daniel Smith

 

[James~P]

daniel.. i have a feeling you may be very right.



my room is completely asymetrical, so standing waves arent a problem.. but now that i think of it the walls are very hard/glossy and no doubt would cause a harsh sound.


i think i'll try holding up some quilts to see if that helps.


where can i buy sound absorbers?

 

[Michael R Price]

Maybe not clipping, although amps can sound harsh when you start to push them. I would guess the weakness of your receiver is the main cause of the harshness problem, even if you're not playing loud enough to clip it. At that level, your speakers' distortion is also a big factor.

 

[ChrisWiggles]

That's a VERY out-dated review on a faulty unit. This has been discussed to death, and is a piece of mis-information.

Marantz is not, perhaps, as well-powered as an HK, but that test from a while back, has unfortunately been grossly mis-used.

(note of bias, i own a 5300)

Furthermore, it could very well be your speakers' tweeters can't handle volumes that high and are distorting and suffering from compression. We don't know what kind of speakers you are using. If they are inefficient in a large room, it could well be that in bass-heavy passages that the marantz is running out of steam.

Lastly, that you are hearing distortions on "s" type sounds tells me that it is not clipping of the amp, but speakers that are under stress and distorting at those SPL levels. What speakers are they? What SPL are you measuring? Is this on movies with bass crossed over to a sub? Or full-range signal in 2-channel.

If the bass is being crossed over (all speakers set to small) then it is almost certainly not the reciever. I'd suspect the speakers for right now, until we can learn more, so I'd hold off on running out and buying a power amp, as it may not help at all.

 

[James~P]

B&W 602 S3s.




like i said, they sound GREAT up to a point, but that point is usually pretty loud on 2 channel music. i dont hear any distortion, just harsh "S" sounds.

 

[Michael R Price]

James,

Harsh sound is a significant distortion. It might not be "obvious" like clipping, but it means parts of your system are being pushed near their limits. I find my system's sound quality starts to degrade with subtle distortion setting in at a level a good deal below what the (correct) speaker and amplifier specifications would indicate.

 

[David Judah]

I own the 602s(I originally used them as fronts, now they're my rears)and they can be pushed pretty hard before the tweeter starts to break up.

It certainly wouldn't hurt to have more amp power, since it sounds like you are cranking it and the amps are just running out of juice as you adjust it up those last few notches(especially since it happened with the other speakers you tried).

It also wouldn't hurt to have that extra amp around since you can always use it if you upgrade receivers or use it as a stepping stone to seperates down the road.

DJ

 

[James~P]

so what would you guys suggest i do?



i cant spend too much money... do i just want a two channel power amp? 5 channel?

 

[Craig_Kg]

It's clipping the treble peaks on the bass peaks (which isn't as bad or noticable as clipping the underlying bass signal).

Try changing your system to all speakers set to small so the bass is redirected to the sub. If that doesn't work, get a nice stereo amp for the fronts (doesn't have to be 200W or anything like that, 75W should do fine). If you get an integrated amp, then you can use that for stereo sources (CD, TT, tape, minidisc) directly rather then running them through the receiver.

 

[David Judah]

Start off with a two channel amp for the fronts.

DJ

 

[Cagri]

Can you measure at what SPL 1 meter away from one of the speakers this starts so that maybe someone with same speakers with a different amp can do the same test and see if their speakers distort same way.

 

[LanceJ]

James: when your system starts to sound bad (in other words, UNmusical) is it at a volume that you want to listen to continuously, OR are you just testing the limits of your system?

Because if you are just testing, then don't worry about buying another receiver or an outboard amplifier.

And a word of warning: whatever is getting stressed out--whether it's the receiver or the speakers--if you keep operating your system that way I'll guarantee that you will eventually burn out at least one tweeter, maybe both. Be careful!!

LJ