Soft Clipping Feature on NAD Amps
Bob Maleki
what this feature does, and the advantages or disadvantages to using it.
The owner's manual (as usual) doesn't really explain the pros and cons
of this function. Does anyone have any insight into this?
Thanks in advance.
Bob
Andy Vaewhongs
According to Stereophile's review of the NAD 304 int. amp. (4/94),
activating the Soft Clipping degrades the sound quality (adds
coarseness or something like that). I personally own a NAD 2100X
amp with this feature, but never bothered (or needed) to use it
so I can't personally confirm this observation.
Andy V.
Brian Odell
is a definite improvement when listening to rock at loud levels (near concert
level, ouch!).
The sound is considerably cleaner and less harsh. At normal volumes, however,
the feature may have degraded the sound a little.
At the time I was driving a pair of Mission 765 speakers which are pretty
sensitive (I don't remember specs, they are also 4 ohms if that makes a
difference). If your speakers are less sensitive then the soft clipping may
be advantageous at lower volumes.
Would speakers with lower impedances benefit from the soft-clipping feature
at lower levels than higher impedance speakers?
Brian
Randy Yates
>I own an NAD amp with the Soft Clipping feature, and I'm curious as to
>what this feature does, and the advantages or disadvantages to using it.
>The owner's manual (as usual) doesn't really explain the pros and cons
>of this function. Does anyone have any insight into this?
>Thanks in advance.
I've owned NADs for close to 12 years now (first a 7140 receiver, now a 2600A
power amp).
The purpose of the Soft Clipping feature is to "soften" the normally harsh
distortion products which come from overdriving the amplifier. Most amplifiers,
when driven too hard, hard limit the output voltage at
the power supply rails of the output stage transistors. Hence the term
"clipping". The abrupt corners in the resulting waveform produce lots
of high-frequency energy which is very grating and irritating. The Soft
Clipping feature rounds those corners out so that the concentration of
high frequency energy is reduced and the resulting sound is a lot easier
to stomach. Another benefit is that such a mode is less likely to
damage your speakers (tweeters).
I suppose a potential con is that the soft-clipping circuit introduces
nonlinearities even when the output is not being overdriven. The
distortion specs seem to deny that problem, though.
You should almost never push the amp that far except when determining
the limit of volume ranges in an experiment. You
certainly should never sit down and listen to music that is regularly
pushing the amp into clipping, unless you happen to like the sound of
distortion.
% Randy Yates % "...the answer lies within your soul
%% EE/Mathematics Student % 'cause no one knows which side
%%% University of South Florida % the coin will fall."
%%%% <yat...@eggo.csee.usf.edu> % 'Big Wheels', *Out of the Blue*, ELO
ron...@ibm.net
>> I own an NAD amp with the Soft Clipping feature, and I'm curious as to
>> what this feature does, and the advantages or disadvantages to using it.
>> The owner's manual (as usual) doesn't really explain the pros and cons
>> of this function. Does anyone have any insight into this?
[quoted text deleted by jwd]
What the soft clipper does is as the name suggests; soft clipping of
the audio signal, thus avoiding clipped signals looking more and more
like a square wave. The square wave would contain LOTS of over
harmonics possibly destroying tweeters (and ears). This is also the
same that happens when you blow a tweeter with a 30 Watter, but it
would survive a 200 W amp.