NEW PRODUCTS: Roundup of latest audio equipment and accessories.
Ortofon Moving-coil Phono Cartridge with "Fine-line" Stylus
Joining the SL 20 E and SL 20 Q in Ortofon's line of moving-coil phono cartridges is the new MC 20, the company's finest such pickup for the playing of stereo and matrixed four-channel recordings. The MC 20 is equipped with a "fine-line" diamond stylus presenting an edge radius of 8 micrometers and an elongated vertical contact span. Frequency response is 20 to 20,000 Hz ±1 dB and stereo separation is 25 dB at 1,000 Hz. The cartridge is designed for a load impedance of 47,000 ohms, and with Ortofon's STM-72 transformer or MCA-76 pre-preamplifier it has an output of 3.5 millivolts for a recorded velocity of 5 centimeters per second.
Compliance is 25 x 10^-6 centimeters per dyne laterally and 15 x 10^-6 centimeters per dyne vertically. The stylus has an equivalent tip mass of 0.5 milligram and the range of recommended tracking forces is 1.5 to 2 grams.
The MC 20 weighs 7 grams. Price: $120. The MCA-76 cartridge pre-preamplifier costs $170; the STM-72 transformer is $37.50.
Sansui's New Vario-matrix Decoder
The latest form of vario-matrix decoding for QS matrixed four-channel recordings is now available in Sansui's QSD-2, an add-on unit designed to be inserted in the tape-monitoring loop of an audio system. The QSD-2 is a single-band device (unlike the three-band QSD-1) said to provide 20 dB of separation between adjacent channels and 30 dB be tween diagonally opposite channels. A function selector has positions for standard QS de coding, four-channel synthesization of two-channel programs, straight-through two-channel reproduction, and for a "phase-matrix" circuit appropriate for the decoding of SQ material.
The QSD-2 has a frequency response of 20 to 30,000 Hz and distortion of less than 0.1 percent at 1,000 Hz. Rated maximum output is 5 volts at 0.5 percent total harmonic distortion. The principal decoding and synthesizing operations are carried out by four integrated circuits. The unit measures 5 x 4 3/4 x 11 3/4 inches. Approximate price: $140.
Phase Linear's Three-section Speaker System
The Andromeda III, Phase Linear's firs loudspeaker, is a stereo system consisting of a single bass cabinet functioning below 100 Hz, a pair of outboard panels for the higher frequencies, and an electronic control/equalization unit (not shown). The system is electrodynamic with passive crossover networks, and it involves twenty drivers in all: two 12-inch woofers in the vented bass cabinet and in each panel-two 8-inch low-frequency drivers, two 4-inch mid-range drivers, and five 1-inch cone tweeters. The tweeters are mounted vertically, radiating into the apexes of diffusion elements that provide horizontal omnidirectionality. Crossover frequencies for the Andromeda are 100, 500, and 3,500 Hz. Overall frequency response is 24 to 20,000 Hz ±.3 dB.
The electronic control unit contains equalization for the bass cabinet as well as frequency contouring controls and unique circuitry intended to enhance the transient response of the tweeters. There is also "spatial imaging" circuitry (switchable) that provides for recovery and special processing of ambient information in the program material to enhance the sense of space. The control unit is meant to be installed between the preamplifier and amplifier of a sound system or in the tape-monitoring loop. Harmonic and intermodulation distortion are less than 0.25 percent and signal-to noise ratio is 100 dB. The system requires an amplifier with a rating of at least 50 watts per channel; it will accept 350 watts per channel of musical material. The two floor-standing pan els measure 24 x 63 x 5 inches; the bass cabinet is 24 inches square and 22 inches high. Both are finished in walnut. The electronic control unit is 7 x 2 x 5 inches. Price of the complete system: $1,185.
New Kenwood Receiver Has Twin Power Supplies
At 160 watts per channel continuous into 8 ohms, 20 to 20,000 Hz, the Model KR-9600 is the top of Kenwood's present receiver line.
Each of the two channels has its own completely separate power supply, ensuring fully independent operation. Harmonic and inter-modulation distortion are both 0.08 percent or less at rated output. Signal-to-noise ratios are 80 dB for the two phono inputs and 95 dB for the high-level inputs.
The KR-9600's FM section has a usable sensitivity of 1.6 microvolts, a capture ratio of 1.3 dB, and alternate-channel selectivity of 83 dB. AM suppression is 60 dB and spurious-response rejection is 115 dB. Stereo separation exceeds 37 dB from 30 to 15,000 Hz, with harmonic distortion rated 0.15 percent in mono and 0.2 percent in stereo.
The KR-9600 has four front-panel meters for power-output level (one for each channel), FM channel center, and FM signal strength.
This last meter can be switched to indicate the percentage of modulation of an incoming FM signal. The power-level meters have two scales calibrated up to 3 watts and to 200 watts; they are switchable between these sensitivities by means of a pushbutton. There are tone controls for bass, treble, and mid-range (defeatable by a front-panel switch), two degrees of switchable loudness compensation, and a front-panel microphone jack with its own mixing control. Up to two tape decks are accommodated, with dubbing possible from either one to the other. The two phono inputs have different sensitivities and overload points for best match to the phono cartridges being used. Approximate dimensions of the KR-9600 are 23 x 6 3/8 x 16 1/2 inches. The front panel has two functional grab handles. Price: about $750.
Bose 901 Speaker Becomes Series III.
The latest evolution of the Bose 901 stereo speaker system, called the Series III, retains the Direct/Reflecting principle and many of the other characteristics of the original 901 design, but it is based on entirely new construction. The enclosure is now a one-piece plastic molding (with decorative walnut panels on the exterior) that provides a semi-isolated acoustic chamber for each of the nine drivers. The chambers are coupled to three tapered cylindrical structures ("Reactive Air Columns") serving as vents; these are said to control low-frequency excursions of the driver cones and their interaction, and to contribute to the very-low-frequency output of the system.
The drivers themselves are also new, incorporating unique molded-plastic frames and other assemblies manufactured to considerably tighter tolerances than heretofore. A direct benefit of all this is a substantial increase in efficiency. According to the manufacturer, the Series III requires less than one-third the amplifier power of the previous 901 system to achieve the equivalent output level.
The electronic equalizer used in the Series III has also been redesigned. It now incorporates a continuously variable high-frequency control with a range of approximately ±5 dB at 20,000 Hz and a mid-bass control operating over roughly the same range between frequencies of approximately 100 to 250 Hz. The equalizer retains a switch that reduces output below 40 Hz, as well as tape-monitor facilities to replace those its installation takes up.
Overall, the Series III has a nominal impedance of 8 ohms. Minimum recommended amplifier power is 10 watts per channel, al though the system can be driven safely with amplifier powers up to 250 watts per channel.
The equalizer has an input impedance of 60,000 ohms, a signal-to-noise ratio of 85 dB, and harmonic distortion of less than 0.1 percent at a 1-volt output. Dimensions of each speaker unit: approximately 21 x 12 1/2 x 13 inches. The equalizer measures 11 x 2 1/2 x 5 inches. Price of the entire 901 Series III system, less stands: $749.
B.I.C.'s Top-of-line Automatic Turntable
The Model 1000 "Electronic" now occupies the top of the B.I.C. turntable line. The two-speed (33 1/3 and 45 rpm) design is belt-driven by a 300-rpm motor with electronically governed speed, permitting continuous variation of pitch over a 6 percent range. A second, independent motor cycles the tonearm.
Basic control functions are accomplished through electronic switching, which permits the Model 1000 to be remotely controlled through a choice of two optional control units, one of which is wireless.
Like other B.I.C. models, the 1000 accommodates a stack of up to six records in its automatic mode; a selector control "programs" the turntable for the number of records in the stack. The turntable can also operate in a single-play mode with automatic arm cycling and as a wholly manual player. The tone-arm with low-mass cartridge shell has an anti-skating adjustment calibrated for conical, elliptical, or CD-4 styli. Stroboscope markings surround the edge of the platter which is illuminated by a strobe lamp.
The B.I.C. 1000 has wow and flutter of less than 0.04 percent (weighted rms) and un weighted rumble of better than-55 dB. The tone-arm tracking-force scale is calibrated from 0 to 4 grams in 1/4-gram increments. On the deluxe wood base with dust cover the turntable has overall dimensions of about 17 x 20 x 7 inches. The Model 1000 alone costs approximately $280. Bases and dust covers are optional at prices ranging from about $8 to $30. Remote-control units cost about $20 for the cable-equipped version and $50 for the wireless version.
Front-loading Cassette Deck From Marantz
The Model 5020 front-loading cassette deck ($269.95) represents the budget-price level in the Marantz line. The control panel situated below two large recording-level meters has sliders for input level (separate for micro phone and line sources), a master recording-level slider, and pushbuttons for Dolby noise reduction, tape type ("normal," chromium dioxide, and ferrichrome), and for a limiter circuit that inhibits recording levels above 0 dB. The transport is mechanically switched by light-touch levers. In addition to the Dolby noise reduction, the 5020 also has 25-microsecond equalization for the accurate de coding of Dolbyized FM broadcasts.
Frequency response is 45 to 13,000 Hz with "normal" tape, 35 to 14,000 Hz with chromium dioxide, and 35 to 16,000 Hz with ferri-chrome, all ±3 dB. Wow and flutter are 0.09 percent. Signal-to-noise ratio is 50 dB without the Dolby circuits, 58 dB with. The dimensions of the deck are approximately 17 1/2 x 5 1/2x 12 1/4 inches. A wood cabinet is available as an option for $35.
Hervic Receiver Has Digital Readout
An LED (light-emitting diode) numerical display of station frequency is the most prominent feature on the front panel of the new Hervic HR 250 stereo FM receiver. The tuning system is otherwise conventional, with a tuning knob and signal-strength and channel-center tuning meters. The HR 250 employs sliders for all other variable controls including volume, balance, bass, mid-range, and treble.
Program sources (selected by pushbutton) include two phono inputs, AUX, and TAPE. A second set of tape inputs and outputs appears as phone jacks on the front panel. Dubbing is possible between the two sets of tape-machine connectors.
Rated at 100 watts per channel continuous into 8 ohms from 20 to 20,000 Hz, the HR 250 has less than 0.1 percent total harmonic and 0.25 percent intermodulation distortion at full power. Signal-to-noise ratios are 72 dB for the phono inputs, 85 dB for high-level inputs. The FM section has a usable sensitivity of 1.7 microvolts, a capture ratio of 2 dB, and AM suppression better than 90 dB. Frequency response is 20 to 15,000 Hz ±1 dB, and harmonic distortion is under 0.25 percent. Image, i.f., and spurious-response rejection all exceed 100 dB. Alternate-channel selectivity is 100 dB. The HR 250 has a brushed black-anodized finish. Dimensions are 17 3/4 x 5 3/4 x 15 3/4 inches. Price: $1,250, with an optional walnut cabinet costing $44.95.
Elpa Marketing, which distributes Watts record-care products in the U.S., announces a new version of the Watts Manual Parastat, the MK IIB. The Manual Parastat is specially designed for records that suffer from greater-than-average surface contamination by dust, dirt, or residues from record-cleaning sub stances or other deposits. It is a hand-held "brush" consisting of three active sections: two velvet-clad surfaces to remove loose debris and a central nylon-bristle brush that pro vides a gentle scouring action when desired.
The bristles have an average tip radius of 0.25 mil, which is said to ensure good penetration of record grooves. The Manual Parastat is supplied with a cover and a dust-proof clear plastic container. Price: $14.95.
Support Systems Inc. makes an adjustable support for a vertically installed bookshelf speaker system called the "Speaker Stand." The four-legged assembly stands 10 inches high and can be altered in width and depth by means of simple screwdriver adjustments.
According to the manufacturer, the Speaker Stand can be made to fit-and precisely almost any available bookshelf speaker system with bottom dimensions of 10 x 8 inches or more. Finish is walnut. Price: $27.50 per pair.
Direct-cut Discs From Audio-Technica
Limited editions of disc recordings made by the direct-to-disc process will be distributed in the U.S. by Audio-Technica. The recordings, manufactured in Canada by Nimbus 9 Productions on the Umbrella label, involve bypassing the usual studio tape recorder and instead applying the output of the recording console directly to the disc-cutting lathe, thereby eliminating any technical limitations in the tape process. The discs will be limited editions, each with its own serial number.
The first U.S. release from Umbrella will be a rock album by the Toronto group "Rough Trade." The second scheduled release will be percussion performances of ragtime pieces by a group called "Nexus." Later offerings will also include classical works. The discs will cost $12.95 each. Further information available from: Audio-Technica U.S., Inc., Dept. SR, 33 Shiawassee Ave., Fairlawn, Ohio 44313.
Speaker-system Kit From Speakerlab
Speakerlab manufactures speaker systems that can be bought as raw drivers and cross overs with enclosure plans, as complete kits with veneered cabinets ready for finishing, or as factory assembled and finished products.
The company's latest offering is the Model S6, a three-way system with a 12-inch woofer, a horn-loaded mid-range with a mouth area of 44 square inches, and a smaller horn-loaded tweeter. The crossover frequencies are 700 and 5,000 Hz, and the network comes with controls that permit independent adjustment of the mid-range and tweeter levels.
The S6 is said to be drivable by amplifier powers as low as 15 watts per channel. Maximum recommended power is 100 watts per channel. Nominal impedance is 8 ohms. Dimensions of the enclosure are approximately 28 x 16 1/4 x 12 inches. As a kit complete with cabinet, grille cloth, fiberglass lining, and finishing oil the S6 costs $215. The drivers and crossover network together with enclosure plans are priced at $161. The complete system, finished in walnut and ready to play, costs $289.
NOTICE: All product descriptions and specifications quoted in these columns are based on materials sup pled by the manufacturer.
Recent fluctuations in the value of the dollar will have an effect on the price of merchandise imported into this country. Please be aware that the prices quoted in this issue may be subject to change.
Also see: AUDIO BASICS: The Volume Control
Source: Stereo Review (USA magazine)