D I O... P A P E R
THE SET & HIGH EFFICIENCY SPEAKER APPROACH WORKS
our audiophile forums, members have a moniker that usually includes
a tag line. Mine say; “If the first watt sucks, why continue?”
Having said that, this is not going to be another hard line
attempt to convince you that SET amps are the only way to get
good sound, or that high efficiency speakers automatically sound
better than anything else.
the years I have learned that for every assumption about audio
there are exceptions that could lead one to conclude the exact
opposite. This “law” encompasses every facet of audio,
from cartridges to loudspeakers and all the cables and components
people for example have assumed that a 2 to 8 watt per channel
SET amp wouldn’t have the balls to get out of it’s own way.
It couldn’t possibly have any real bass, but we hear the
midrange is to die for.
people would also assume the only way to hear any dynamics from
a flea powered amplifier is to use big nasty horn speakers so
really what is the point?
of these assumptions are probably a side effect of the general
direction that high-end audio has taken since the 1960’s. Solid
state has made high power affordable for everyone so the loudspeaker
industry responded by making speakers less efficient to both
reduce their size and flatten their response.
popular belief, you do not need horn speakers to use or enjoy
a SET amplifier. You can also find many horn speaker designs
that sound wonderful, better than wonderful in fact, so the
question then becomes this:
are the advantages are to using SET amps with high efficiency
answer this, lets start with the advantages of a SET amplifier
over any other type. A Single Ended Triode is the simplest
circuit design there is, using the least number of parts. Typically
this is a driver stage coupled to a single output device. Triodes
do not require negative feedback, something found in most all
push-pull circuits, solid state or tube. Negative feedback
is used to lower distortion specs and in the case of solid state
devices it is often the only thing keeping the transistors from
exploding all over the inside of your amplifier. Feedback
a problem? If you don’t mind the time smear it creates
and the resulting 2 dimensional sound stage, then no I guess
it’s probably not.
from the amplifier’s superiority by simplicity, there is a more
profound reason for using SET amplifiers. The magic predominately
lies in the first watt. By magic I mean inner detail and
most of the dynamics. For example, a pair of 96dB speakers playing
with one watt of power against the average noise floor in your
listening room (55dB) is 40 dB of dynamic range. (96 –
55 = 41 dB) Adding a second watt increases the dynamic range
by only 3 dB. For every additional 3 dB you need to double your
power. This should clearly illustrate that there is over
10 times the dynamic range in the first watt as there is in
brings us directly to loudspeakers. A typical loudspeaker
today is 86 dB efficient with 1 watt. It also usually
has a complex crossover that attempts to keep the frequency
response and impedance flat. The crossover alone will
usually dissipate a significant portion of the first watt as
heat before it even reaches the drivers. To reach the
same loudness level as the 96 dB speaker will with 1 watt requires
over 8 watts on the 86dB speaker. If we used 2 watts on
the 96 dB speaker the other would require 16 watts to keep up.
If we used 4 watts on the 96 dB speaker the other would
require 32 watts to keep up.
problem here is resolution. If you can’t hit a listening
level with the 1st watt, you’re not likely to hear what’s happening
in that 1st watt. For a driver to achieve a high efficiency
it’s moving parts must be low in mass. That makes it dramatically
faster or more accurate than a speaker with heavier moving parts.
If you like inner detail and want to hear all of the textures
and layers of a good recording you need fast, efficient and
good SET amp combined with a single full range driver with no
crossover or a simple 2-way using minimal crossover parts on
the tweeter only, has a purity and depth that you simply don’t
find in more conventional systems. It is a benchmark for
coherency, and noted for its ability to create hauntingly real
holographic sound stage. Bass and dynamics with this combination
sound more realistic in part from the tremendous speed and in
part from the coherency.
consulted many people about their audio systems, and the most
common complaints include dry somewhat fatiguing sound with
a fairly boring soundstage followed by the realization that
it simply doesn’t connect you to the music emotionally like
it could. Experience has taught me that by far the easiest
way to get a liquid sound that becomes holographic with stunning
clarity and detail, something that excites the listener, is
to set him up with an SET and simple pair of efficient speakers.
It also usually ends up being the least expensive solution.
biggest conformation of this is reports from audiophiles who
used to have several hundred watts and many thousands of dollars
invested in show winning audio gear, but now report that even
a good 2 watt SET on efficient speakers has better dynamics
and weight which they find simply amazing. If you’ve ever
observed how audiophiles rotate through audio gear during their
lifetime you might also find it interesting that the ones who
finally land on SET amps and good speakers seldom find anything
they like better.
bigger is better mentality that is directly connected to more
expensive the better is certainly the handicap that stunts most
audiophiles from discovering truly high fidelity sound. Will
the guys at the audio salon laugh… yes the will. Will
your fellow audiophiles laugh when they hear you sold everything
and got a 2-watt amplifier… yes the will. Is this important
to you? Only you can decide, but I would suggest it has little
to do with high fidelity.
closing, remember this – It is dangerous to place amplifiers,
speakers, cables etc., into neat little categories in an effort
to make some sense of it all. Not all tube amps sound
good. Not all solid- state amps sound bad. With the Internet
audiophiles have been set free to research things in a far more
unbiased way then ever before. Before the Internet there
were only trade magazines, and manufacture’s literature to educate
us all and it goes without saying – fairly biased sources. Of
course the Internet is full of misinformation, some intentional,
some out of ignorance, but at least you can find all sides and
make your own determinations.
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