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Peter Wieck Peter Wieck is offline
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Default Power amplifier clip indicator

On Thursday, April 14, 2016 at 11:15:03 AM UTC-4, August Karlstrom wrote:
On 2016-04-13 23:29, Peter Wieck wrote:
On Wednesday, April 13, 2016 at 2:57:03 PM UTC-4, August Karlstrom
wrote:
How come power amplifiers for the consumer market typically never
include a clip indicator? Would such a feature have a negative
impact on the fidelity?


-- August


Many of the higher-end amps did have such indicators. But when
fidelity started taking a back seat to costs, and when two-channel
stereo essentially died in the consumer market, both conditions
mitigated against this feature.

I keep two HK amps with lead displays for power-out, right up to
clipping. Dynaco, McIntosh, SAE, Phase Linear and quite a few others
used either meters, LEDs, indicator lights and any of several other
means to convey clipping. Until a few years ago, I also had a Dynaco
ST416 with an LED display, and its older brother, the 400, had meters
as an option.

These days, I believe that Yamaha, Onkyo and a few others still offer
this feature.

=20
Then there are more models with this feature than I thought.
=20
You sometimes read discussions about "How many watts do I need." A clip=

=20
indicator is an honest way for an amplifier to say "I give up, you need=

=20
a more powerful amplifier" rather than trying to camouflage the problem=

=20
with technologies like soft clipping etc. If the music doesn't sound=20
right at higher volumes, how can you tell if it's clipping or if the=20
problem is elsewhere?
=20
=20
-- August


Well.... How may worms are you prepared to herd based on how many cans of s=
uch are you willing to open all at once?=20

There is clipping, and there is clipping. I keep Maggie speakers rated at a=
bout 83dB at one watt at one meter. 83dB is a reasonable but low average li=
stening volume. If I am playing one or two of the very few sources I have w=
ith a 30dB P/A (peak to average), then I would need an amplifier capable of=
100 watts for the peaks, and also capable of producing clean sound at 0.1 =
watt. That covers the 30dB range.=20

I have two (2) amplifiers capable of doing that for *BRIEF* peaks, and two =
capable of delivering a clean 100+ watts all day and all night. Note that a=
t the peaks, I am delivering 103dB of sound. And, my ears will not be bleed=
ing.=20

Or, let's suggest that I am playing a very compressed source such a Heavy M=
etal, where the P/A seldom exceeds 10dB. And I want it LOUD - so, I am *ave=
raging* at 100 dB. Meaning my amp will need to give something on the order =
of 75+ watts, average, and peak at 500+/- or so. I have _no_ amplifier capa=
ble of doing that safely. I have only two that will make the average safely=
.. Few exist as well.=20

Now, for the real world:=20

If I am listening in my radio room, about a 12 x 15 x 9 *FOOT* cubic rectan=
gle using 86dB @ 1watt speakers playing classical music, orchestra + solo i=
nstrument, my systems in that room are perfectly comfortable with 30, 75 an=
d 100 watt amplifiers (WPC/RMS) respectively as I will NEVER even wish to p=
lay loud enough to clip. In point of fact, my flea-power Dynaco ST35 (17 ve=
ry anxious WPC) is effective for 90% of my listening in that room.=20

And the Maggies seldom pin the LED display, again unless I am playing one o=
f my few very wide range sources. I very nearly never play heavy metal.=20

Peter Wieck
Melrose Park, PA