Mark Levinson Reference Preamplifier N32 - Manual (Page 7)

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tion, optional custom termination is provided via a pair of gold-plated
terminal posts within each phono module. No soldering is necessary
when using these binding posts.
ac regenerated
power supply
The foundation upon which any audio component is built is the power
supply. Without an extremely clean, noise-free power supply, no audio
circuit can live up to its potential.
Unfortunately, we live in a world in which the quality of AC mains
power is increasingly in question. The modern conveniences upon
which we have become so dependent introduce line noise, spikes, and
various other irregularities. Everything from refrigerators to televisions
and computers inject their peculiar contaminations back onto the AC
line, making it increasingly difficult for a high performance audio com-
ponent to live up to its potential.
In the Nº32, we solve this problem by becoming our own power utility.
Strange as this sounds, it is effectively true. There are two independent,
unusually high quality power supplies dedicated to the two audio chan-
nels. The DC power from these supplies is then used to power a special
power amplifier that is fully optimized for reproducing only one fre-
quency: 400 Hz. This extremely pure 400 sine wave is then rectified, fil-
tered, and regulated again to create extraordinarily pure DC power for
the use of the critical preamplifier circuits.
By creating our own dedicated 400 Hz AC power and then using that to
create “second generation” DC power for the audio circuitry, we keep
the contamination of the modern electrical grid at a safe distance from
the sensitive audio circuits we look to for our musical enjoyment.
The phono preamp modules use the same AC-regenerated power sup-
ply used by the rest of the Nº32 reference preamp. By designing the
preamp module inside the Nº32 preamp, we were able to integrate
power, ground and signal distribution with the line level preamplifier
as if the phono preamplifier was simply another stage of the overall
preamplifier circuitry.
Locally, a discrete, high-performance regulator provides each module
with a fast-response, low noise
±
15 supply voltage. A multilayer Arlon
25N printed circuit board with extensive ground and power plane con-
struction carries the regulated power to the active circuitry.
fully balanced design Fully balanced circuitry is more than a tradition at Madrigal. The per-
formance advantages are as clear on the test bench as they are in the lis-
tening room. Logic dictated that we offer the best performance avail-