will help the novice build a safe and functional project. Of course, a each project could fill the entire book if it were fully explained. And the rank beginner certainly will need some help to build even the easiest project in this book.

The Circuits
   As I do, Mr. Rozenblit places a great emphasis on the circuits themselves, so the question to ask is Just how good are his circuits? Solid and competent is the short answer. He values simplicity and simplicity is paid a tribute by all his circuits. Making a reliable, functional, simple circuit is much more difficult than making a complex mess. Einstein was right, everything should be made as simple as possible, but not simpler.
   
Recommendation
    If you decide to build one of his projects, actually do just that; do not build your own hotrod version of it. If he specifies a 12AU7, do not replace it with a 5687; if he specifies DC on the heaters, do not use AC. This approach precludes the temptation to call him and bother him with questions about a project he did not design. Second, he will receive all the credit or blame for what is made.

   If after a week, you feel the urge to modify his work, go for it; but please, give his work a fair chance first. (The majority of help I have given friends with audio equipment has been for hotrod jobs. Projects that placed 100 volts too much voltage on the electrolytic capacitors used, that overtaxed the power transformer used, that failed to realize that all 9 pin tubes do not share the same pin out, that mis-wired the amplifier with very expensive silver wire.)

The Transcendent OTL
   This amplifier is different from most tube amplifiers in that it uses neither an output transformer nor an output capacitor. It is a push-pull Class AB amplifier (unlike far too many makers of high end gear, Mr. Rozenblit knows how to use a calculator; he is very upfront on not only the Class AB biasing of his amplifier, but also frank in explaining why Class A operation would not work as well in this amplifier). This amplifier is capable of putting 80 watts of power into an 8 ohm load and can drive 50 watts into 4 ohm loads. It uses eight EL509 sweep tubes per channel wired as triodes. It has received a Class A rating from Stereophile and is on my very short list of amplifiers I would love to hear.

A greatly simplified representation of the Transcendent OTL

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