I performed a full set of measurements on the M28 (serial number 1006) using my Audio Precision SYS2722 system (see www.ap.com and the January 2008 "As We See It"). As the Bricasti amplifier is specified as having a maximum output power of 200W into 8 ohms, I preconditioned it before the measurements by running it at one-third that power, 67W, into 8 ohms for an hour, following which the top panel was warm, at 99.3°F (37.4°C), and the side panel covering the internal heatsink was only slightly hotter, at 106.7°F (41.5°C). The THD+noise percentage at this power…
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Teachers can change your life and never was that more true than with a Miss Wagner, my long ago English teacher who looked so fine in her mini-skirts and frosted hair. When the schoolboy jungle telegraph somehow sussed out the fact that her first name was Julie, a collective shiver ran through the male animals in the class. Lust, which we mistook for love, was in the air.
While the mass ogling was in full swing and the sickly sweet aroma of jittery, prepubescent testosterone hung heavy in the classroom, I was equally interested in Miss Wagner’s musical selections. Seems she was a bit of a…
In the continuing chronicles of indefensibly cheesy 70s metal bands…
So the story goes that after Caress of Steel stiffed, undoubtedly because of tracks like the super indulgent and fairly leaden, 20-minute, “Fountain of Lamneth,” an early misguided attempt at heaviosity, the Canadian trio Rush knew they were about to be dropped by their label, if not the music business, the listening public and the entire human race, so they figured WTF. Deep into what Geddy Lee now calls their “kimono period,” the band wrote and recorded, 2112, (“Twenty One Twelve”) a record that makes them incredibly…
Two years ago, I hailed Steve Coleman’s Functional Arrhythmias as a career breakthrough. His new CD, Synovial Joints (on the Pi Recordings label), is his masterpiece—a thrilling kaleidoscope, densely polyrhythmic, but also brisk and airy: music for serious listening as well as dancing in your head and on your feet.
Coleman, 58, is a master alto saxophonist, conceptualist, and synthesizer, fascinated with the biological roots of music. Functional Arrhythmias referred to the interactions of irregular heartbeats and contrapuntal nerve impulses in the human body. Synovial Joints refers to the…
The Lazarus, a slim, quite elegant unit finished in black with red and gray legends, lived up to its advance billing: it literally rose from the dead! Out of its coffin (ie, shipping box) and plugged into the wall, it showed no signs of life. Troubleshooting revealed a blown AC mains fuse. That in itself was not a major problem, but what worried me was the root cause of the trouble. Preamplifiers as a rule are not power-hungry, so a current surge at turn-on sufficient to destroy the 250mA slow-blow mains fuse appeared symptomatic of a major circuitry failure.
After describing the problem…
Sidebar 1: Absolute Issues
Why should the Cascade Basic be so sensitive to polarity reversal? I can only speculate and point an accusing finger at the possibility that inherent phase-response errors are compounding the effects of polarity reversal. A nonlinear phase response will produce a frequency-dependent phase shift of harmonics in a complex tone, the end result being a distortion of the signal waveform. So the broad issue is whether the auditory system is sensitive to waveform distortion or to changes in waveform slope (a polarity reversal changes the slope of the signal; ie, a…
In hindsight, it was inevitable that two sophisticated digital audio technologies—software-based digital filters and Bitstream D/A converters—were destined to be married in one product. The software-based D/A converters offered by Krell, Wadia, and Theta all used multi-bit ladder DACs, and Bitstream-based units have previously relied on off-the-shelf digital filters.
Having auditioned both types of technologies individually, I've always wondered how they would sound together. This is an important question; fewer and fewer IC manufacturers will make multi-bit DACs as the world—for better…
Sidebar 2: Measurements
Intrigued by Dick's description of the Lazarus preamp's phono stage as having "zippy" treble transients, I ran a low-level 1kHz squarewave through the magazine's inverse RIAA network into the Cascade Deluxe's phono input (set to 47k ohms impedance). Fig.1 shows the result at the tape output sockets: excessive leading-edge overshoot which will certainly lend an "etched" quality to the sound in the treble, as well as exaggerate the audibility of disc surface noise. Note also the slight uptilt to the plateau of the waveform, implying too much upper-bass energy. The…
Parts quality is very high. The capacitors associated with the Bitstream DAC are primarily polystyrene, all resistors are 1% metal-film types, and four of the resistors in the feedback loop are $3 non-inductive wirewound types. These resistors reportedly had a huge effect on the Prime's sound quality. In addition, a few Teflon capacitors (very expensive) are used in critical audio stages. The metal work is zinc over copper over steel, and the pcb is glass epoxy.
Overall, the Prime is an engineering marvel for its modest price. There is far more inside the unit than one would expect for…
Sidebar 3: Specifications
Description: Tube preamplifier with hybrid solid-state/tube phono design. Frequency response: 20Hz–20kHz, +0/–1dB. High-level sensitivity: 100mV in for 1V out. Phono sensitivity: 0.2mV for 0.5V output at 1kHz. Phono overload: 50mV (no frequency specified). Phono input impedance: adjustable from 26 ohms to 47k ohms in 8 steps, in parallel with 25pF. Line input impedance: 100k ohms. Measured output impedance: 1030 ohms.
Dimensions: 19" W by 10" D by 2" H.
Serial number of sample tested: 2062.
Price: $1199 (1989); no longer available (2015). Approximate…