January 8, 2002
Can you explain clipping to me? I was recently
running a Bryston 4B ST amplifier through some Bose 901s at just after the halfway mark on
the preamp. The amp's clipping light started coming on, and when I tried to inch up a
little further, the system started distorting, so I backed off the level. The amp is rated
at 250 watts. According to Bose, the speakers are rated to handle 450 watts RMS. What
caused the distortion? Someone told me that it was the speakers, but that doesn't seem
reasonable since they are able to handle much more power than the amp can put out. Isn't
it more reasonable to think that the amp was distorting?
Ken Simpson-King
Clipping is the amplifier hitting its
power limitations by being overdriven. The amplifier shears the waveform (clips it), which
creates a distorted signal. Be careful, because clipping can severely damage loudspeakers,
especially the high-frequency drivers. Whether your amp is actually clipping or it's the
speakers that are distorting due to too much power there seems to be an incompatibility
between your amp, your speakers, and the volume levels you like to listen to. The solution
to your problem is to either lower your listening level, choose more efficient speakers,
or go to a larger amplifier like Bryston's 7B ST 500W monoblock.
January 7, 2002
I will be buying a new stereo system for a
household in the next six months or so, and I would like to have some information on
systems that would be suitable for the space/rooms. I have been out of the loop for many
years (kids that like to play with buttons and speaker cones), so I have no expectations,
as well as no budget yet. The info about my listening space I can provide, but because
there are no real stereo shops that are in my area, it is difficult at best to find help.
Can you please either point me in the right direction or give me some basic knowledge for
good buying a system?
Tom Roehlke
A cost-effective stereo system can be
assembled with a basic source component such as a DVD player (which will play CD and DVD
movies), a receiver (which will provide you with a tuner as well), a pair of speakers, and
cables to connect everything. Not only can you attain good performance, but you have an
upgrade path by adding surround speakers for home theater if you choose to do so in the
future. A DVD/receiver-based system can be purchased relatively inexpensively and provides
excellent flexibility. A setup consisting of the above components is also widely available
from most electronics retailers. In terms of find a place to purchase, be thankful for the
Interent. You will find plenty of good information here and on other sites that are part
of the SoundStage! Network.
January 5, 2002
I recently bought a used Cambridge Audio A300 integrated
amp to replace my old NAD 310 (which is a great little unit) and have experienced
"clipping of the beat" at higher volumes. The A300 is in immaculate condition
and came with the original box and packaging. I am confident that it is not damaged, as I
connected some old speakers I found in the basement (Sony and Aiwa) and had no problems.
The signal source is my Nakamichi MB-2s CD player,
connected to the A300 via RCA cable, which drives a pair of JBL Studio Series S26
speakers. At higher volumes (by "higher" I mean the volume knob is turned about
60% to max), the sound begins to clip. It begins with the bass beat and as I continue to
turn the volume up, more and more of the audio clips out, until barely anything is left
discernable in the vocals.
Len Epelbaum
Without hearing your system it is difficult to say
definitively, but my guess is that you are correct. The other alternative is that your
speakers are being overdriven and that is causing the distortion you are hearing. The
Cambridge amplifier has a modest rating of 50Wpc, and at the volume levels it appears that
you are using, especially with dance, techno, or hard-rock music, that simply may not be
enough power. NAD amplifiers, although conservatively rated with respect to power
specifications, have always possessed reserves that belie their size. Compared with the
NAD 310, your Cambridge Audio A300 may not be able to keep up in terms of power. I'm sure
it does other things well, but when it's time to rock, you just need more juice.
January 3, 2002
In a December post, you discuss moving a small speaker
toward a wall, but not too close, to improve the bass response. I would like to place my
speakers near to the narrower wall (in a 14' x 28' room) for aesthetics. My system is
intended for both audio and home theater. Should I avoid a larger speaker to prevent an
overwhelming bass response? Would a different speaker technology work better?
Eric
There's conventional wisdom, and then exceptions to the
supposed rule. Conventional wisdom is to avoid larger, rear-ported speakers when in a
smaller room, especially if they need to be placed close to a wall, which reinforces bass
frequencies. While this is many times true, in some cases you can get around that,
particularly if the design addresses this issue in some way. I've had very large speakers
in a medium-sized room work great, only to find that a smaller model exacerbates a bass
anomaly that renders the speaker unlistenable in the same room. This is why a home
audition is always the surest way to determine what works and what doesn't.
Your room is fairly spacious, so a larger speaker might
work. A better alternative may be a subwoofer/satellite system. This arrangement would
afford you the opportunity to experiment with the placement of the sub to enhance bass,
while placing the bass-challenged satellites close to a wall. This could give you the best
of both worlds.
January 2, 2002
I'm looking to develop a home-theater system. I currently
have a pair of bookshelf Canton satellites with a Velodyne subwoofer. I'd like a nicely
matched speaker setup. The entertainment wall gives me the option of placing in-wall
speakers or having small-to-medium-sized cabinet speakers placed on a shelf. Are in-wall
speakers as good as comparable cabinet speakers?
John Hopkins
In-wall speakers are becoming more prevalent, and
therefore the designs are improving at a substantial rate. So, yes, they are an option. In
your situation, it is important to match your front speakers to the rear channels. If
Canton has in-wall speakers, you could look at those, but regardless, I would advise
staying within the brand for purposes of continuity. This will provide you with a seamless
surround experience because the speakers would be matched in their performance
characteristics. I do know Canton has a fairly diverse lineup, so you should have plenty
to choose from, giving you a good chance of assembling a terrific system. The Velodyne
subwoofer should do extremely well in a theater system too, so you have a leg up by having
that already.
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