Red Rose Music 5 owner manual A Message From Victor Tiscareno

RED ROSE MUSIC

A Message From Victor Tiscareno:

Chief Designer, Red Rose Music

At Red Rose Music we have built our reputation and design philosophy around the use of high- performance power supplies in vacuum tube components. We believe that a good circuit can only sound as good as its power supply. Our experience has taught us that providing the best possible sound requires careful planning, design and execution. But maximum performance from these areas requires meticulous attention to the power supply design for each circuit in the amplification chain.

A tightly regulated power supply can improve the sound of any audio circuit. Vacuum tube circuits in particular operate at much higher voltages and impedances than solid-state circuits; therefore the potential for both noise and signal corruption is greater. And it is well known that circuits with triodes realize the greatest benefit from precision regulated, low-impedance power supplies.

Pre-amplifiers and amplifiers operate in basically the same manner: they take low-level signals and boost them to useful levels. In a pre-amplifier, the current draw of a Class A circuit causes relatively low fluctuations on the power supply. The power supply in a two-channel pre-amplifier must remove the inherent noise (ripple voltage) from the incoming power source, isolate the signals from the opposite channel, and reduce or eliminate any modulating effects between gain stages. A power amplifier begins with the signal from the pre-amplifier stage, including all the noise produced in the pre-amplifier. Therefore, the quality of sound produced by a power amplifier can be no better than the quality of the signal that amplifier receives from the pre-amplifier. This is the well-known Ògar- bage in, garbage outÓ principle.

Static bench measurements donÕt always reflect the improvements produced by a regulated power supply, but listening tests are extremely convincing. An improved power supply produces subjective improvements in both noise reduction and transient signal performance.

There are three basic ways to design a power supply for an amplifier or a pre-amplifier:

1.Starting with a power transformer, feed the raw AC to a bridge rectifier, and then filter and smooth it to an unregulated DC voltage level, using either capacitors or large inductors. Regulation of this type of power supply is produced by the impedance of the transformer winding and the amount of capacitance used for filtering. The unregulated voltages are split off to various points in the circuit, where additional, localized filtering is applied in order to isolate the gain stages from one another. Because of the relatively low cost, most amplifiers use this kind of design.

2.The next step up in power supply sophistication is to use a single regulator that splits off DC voltages to various points in the circuit. In most cases, a single regulated supply feeds all of the amplifier stages, but more costly designs use separately regulated supplies at key points in the circuit. The choice between a single supply and multiple supplies is a trade-off be- tween cost and performance. More than 99% of all amplifier manufacturers have chosen not to regulate the output stages of their amplifiers.

3.The best (and most expensive) design approach is to use separate regulators for the main power supply and the gain stages, in order to isolate the circuits. This is the approach used in Red Rose Music amplifiers and pre-amplifiers.

Of course, the design of the power supply is not the only thing that effects the sound of an amplifier.