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HOW TRUTHFUL are the ads describing high fidelity equipment? With militant consumer groups now prodding the U.S. Government to crack down on misleading advertising practices, this is a good time for audio manufacturers to take a fresh look at their ads as they relate to the latest regulations.

Self-regulation by the industry has largely swept away the overblown, exaggerated performance claims that marked the stereo "power race" of a few years ago.

Industry committees within the Institute of High Fidelity (IHF) and Electronics Industry Association (EIA) argued heavily and finally adopted standards that manufacturers (and their admen) could live with, so that when the Federal Trade Commission (FTC) began probing the audio makers' truthfulness in advertising, it found them ready and willing to comply — and, in many cases, already using standards of measurement even more stringent than those imposed by the FTC.

Pick up the "spec sheet" for an amplifier or receiver from any of the leading component manufacturers and you'll find, at least in the fine-print technical specifications, that truthfulness prevails. Here's where the engineers let it all hang out. They have to, because the specs state levels of performance determined by standard tests that can be duplicated by any laboratory. Publish a phony spec and the truth will be out in no time, along with the engineer's reputation. The specs don't lie.

But look again, and you'll find several sets of specifications for the same piece of equipment, each set arrived at by employing a different standard of measurement.

One leading 4-channel receiver offers six different power ratings, all of them valid:
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• -28 watts RMS per channel, with all channels driven into an 8-ohm load, measured at 1,000 Hz.
• -25 watts RMS per channel, with all channels driven into an 8-ohm load, measured from 20 to 20,000 Hz.
• -35 watts RMS per channel, with each channel driven into an 8-ohm load, measured at 1,000 Hz.
• -52 watts RMS per channel, with each channel driven into a 4-ohm load, measured at 1,000 Hz.
• -180 watts IHF music power at 8 ohms.
• -260 watts IHF music power at 4 ohms.

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The most stringent (einleuchtend, schlüssig) of these measurements, with all channels driven and power measured throughout the audio bandwidth of 20-20,000 Hz, adds up to only 100 watts RMS, a far cry from the 260-watt IHF "music power" rating. The latter figure smacks of the old days when a big power rating was an advertising "must." It is higher because only one channel at a time is measured and short bursts of power are applied instead of the continuous power used for an RMS rating.

The key to any power rating is, of course, the level of distortion. The above model's rating of harmonic and intermodulation distortion is 0.3 per cent. The more you increase the stress on an amplifier's output stage, the more quickly distortion rises to the rated level, and the lower the power level achieved by the amplifier. Since a music power test puts an amplifier's circuitry under much less stress than continuous power, it yields more impressive figures.

Because a music power test is also more difficult to duplicate exactly in the laboratory than the more straightforward continuous-power test, it is less valid as a comparative measure of performance. Consumer testing labs and most audio journals stopped publishing music power ratings long ago. More recently, when the FTC began its study of the power ratings controversy, the industry responded by urging manufacturers to stick to RMS, and the highly suspect music power claims virtually disappeared. Now they are starting to creep once again into competitive advertising, and it's a bad sign.

The latest industry rules, which have the necessary clout now that the FTC is making them into law, provide that advertising must clearly indicate how the power rating is arrived at — the maximum distortion, the range of frequencies measured, the load (in ohms) and whether the channels are driven simultaneously or one at a time. A power claim for a receiver or amplifier that is not qualified in* this way is not sufficiently informative. And, if the stated wattage turns out, instead of RMS, to be a music power rating, the ad is downright misleading.

To a copywriter, "260 watts" has a lot more "zing" than "25 watts per channel RMS continuous power at 8 ohms with all four channels driven from 20 to 20,000 Hz and THD less than 0.3 per cent." Since there will always be an adman, looking for smoother, slicker-sounding ways to describe the product, the really meaningful specs are only rarely given prominent space in an ad. But they are there for the alert, reader to find, even if only in the fine print. Because every manufacturer of quality equipment publishes complete specifications. And the specs don't lie.
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STARTING THIS MONTH, our stand-by-stand report of new products seen at the big Consumer Electronics Show - Chicago June 9-12. 1974 - Off Duty / Europe / Sept. 74
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Latest console stereos from Admiral feature a passive speaker matrix called Quadra IV for simple decoding of matrixed quadraphonic records. The circuit requires only an extra pair of loudspeakers, available optionally with Admiral's new consoles, the "Tosca," "Valley Forge" and "Espana." There are also two discrete 4-channel models, the "Medici" and "Aragon," with built-in cartridge tape player (for discrete 4-channel tapes as well as conventional 8-track), and an SQ decoder. The front speakers are separate units styled to match the equipment cabinet while the rear speakers are smaller bookshelf models. Admiral also has two 4-channel compacts, one with a tape player built into the AM/FM-stereo control unit, the other with record changer in addition to the tape player. Both compacts have four identical two-way speaker systems, and circuitry includes an SQ decoder.

While most single-play turntables offer at least a modicum of automatic features, the AR turntable has for years been strictly manual — you pick up the arm, cue it by hand into the groove and, when the record has played, you pick up the arm once again and return it to the arm rest. But, after more than a decade of stubbornly resisting change, this popular belt-driven turntable will be available with built-in viscous-damped cue/ pause device, the new model to be known as the AR XB. Another version, the XB-91, will include a premounted M91 ED cartridge from Shure.

Why "pi" ?, asked visitors to AR's stand at CES, as they auditioned the company's new speaker, the AR pi/one. The explanation is that pi is a factor in measuring the solid angle of radiation of the speaker's output. AR judges the angle to be 2 pi steradians when the speaker is wall mounted, 4 pi steradians when free-standing, or simple pi when placed in a corner. The AR pi/one speaker's 3-position "woofer environmental control," say the designers, is an entirely new switching network specifically designed for the system's 12-in. woofer. For the dome midrange and dome tweeter, the controls provided are attenuators of the conventional type. Price of the AR pi/one will be substantially higher than that of the AR-3a.

• Anmerkung : Bei den internationalen Tests hat sich herausgestellt, das war genauso großer Marketing-Quatsch wie später bei DUAL der so hochgepowerte ULM Tonarm.

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Though long familiar to exchange customers overseas, Aiwa was a virtual newcomer at CES, as the company is now establishing a U.S. subsidiary for the first time. For this new invasion of the Stateside market, Aiwa has a line of cassette recorders that includes two variable-speed models useful for language study. The Aiwa TP-770 has a pitch control permitting playback to be slowed down by as much as 20 percent or, if desired, speeded up by 50 percent for quick review of recorded material. Model TM-405 can be switched so the student records on one channel while listening to the teacher's voice on the other channel. He can then replay the tape to compare the two voices. This model offers speed control of ±10%.

Other Aiwa recorders at CES included the AD-1500 cassette deck with Dolby noise reduction and automatic switching for chromium dioxide tape; a lower-cost model AD-1300 which also has Dolby; and model AD-1200, a budget-priced deck with Dynamic Noise Limiter (DNL), a noise reduction circuit that operates only in playback. Among Aiwa's portable cassette models are the new TP-747 midget recorder with built-in electret condenser microphone, and the TPR-930 radio recorder with four built-in speakers and full stereo capability as well as integrated 4-band radio. Also new at Aiwa is the AP-2050 belt-driven turntable with automatic arm return and shut-off.

While Dolby noise reduction circuitry is now virtually a "must" in top quality cassette machines, only a handful of open-reel tape recorders offer built-in Dolby and it's usually limited to the maker's highest priced model. Evidence of a change is Akai's 4000DB, newly introduced Dolby version of the company's popular-priced 3-head, one-motor tape deck. In the States, the 400DB will sell for $369.95, $70 more than the non-Dolby 4000DS already available.

The new GX-600D and GX-600DB (the latter with Dolby) raise to three the number of 10 1/2" reel machines in Akai's stable. Also new in the States and in Europe (it was introduced earlier in Pacific exchanges) is the GX-400DSS, top-of-the-line 4-channel model with closed-loop dual capstan drive and automatic reverse. It also features "quadra-sync" for overdubbing on any channel without time delay. This is achieved by switching individual tracks of the recording head to playback mode to monitor previously recorded material while recording additional tracks. The GX-400DSS offers four of Akai's glass-and-crystal heads and all-solenoid controls with logic circuitry. Stateside price is $1,495.
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Now owned by Capitol Industries-EMI, the Audio Devices people are changing the name of their blank recording tape to "the music tape" and packaging it in candy-apple red. According to Capitol, the package contains top-grade tape of high-output/low-noise oxide, but the technical jargon is being dropped in order to eliminate confusion over various oxides, and thus appeal to a broader market of tape users. The music tape by Capitol will be offered in cartridge, cassette and open-reel packages, the cassettes available either singly or in twin-cassette "stak-pak" boxes that can be interlocked to form a tiny chest of drawers.
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Packaging of cassette tape for mass appeal is now so competitive on the Stateside scene that the dizzying array of packages from Audio Magnetics is worthy of special mention. The company's Tracs tape is now promoted as "the great cassette rip-off" displayed in a long roll of transparent plastic bags on a drum topped by a "Rip Off" sign. Another Tracs promotion is the "three-hour special," a bag containing tape sufficient for three hours of recording (either two 90-minute cassettes or one 60- and one 120-minute cassette). Latest is the Tracs one-cent sale of one C-60 cassette at the regular price and a C-30 cassette for one cent more (with the penny refunded — it's inside the special package). Audio Magnetics also has a new, higher-priced tape formula called XHE (for "extra high energy"). It is packaged in a jam-proof cassette containing plastic guides that control winding and rewinding of the tape—called "special mechanics" and similar to the tape guides in BASF's cassettes.

Now there are three groups of BASF cassettes. The company announces that the budget-price line, now called SK/LH, has been upgraded with higher output tape and its packaging redesigned. The medium-price range, called LH Super, is of the high-density ferric oxide type, while the top of the line is BASF Chromdioxid. All three tapes are packed in jam-proof SM (special mechanics) cassettes.

No longer specializing in British-made audio equipment, "British Industries Company" has adopted the name "BIC" and offers a new line of loudspeakers and belt-driven record players. The latter, called "Programmed Turntables" by BIC, feature a control that can be set to repeat a single record up to six times before the machine shuts itself off.

The mechanism will also play up to six records automatically. Because the user presets the program, the elaborate changing apparatus of gears and cams activated by an automatic spindle is greatly simplified, according to BIC. The new turntables use a 24-pole, 300-rpm synchronous motor that, on the higher-priced ($199.95) model 980, is controlled by an electrically generated reference frequency and can be adjusted ±3 percent with the built-in strobe and pitch control. On the gimballed tone arm mount there are anti-skating and stylus force adjustments for elliptical or conical styli. On the cueing control, rate of ascent or descent can be continuously varied 1-3 seconds.

BIC loudspeakers, called Venturi, are high-efficiency designs employing a tuned duct coupled to the woofer. Their midrange driver is a horn made of glass-filled polyester, flared like a pyramid so dispersion will be the same whether the cabinet is placed vertically or horizontally. A super-tweeter of the dome type completes each 3-way system, and under the removable molded foam grill are controls that include a switch to adjust the relative level of the midrange according to the Fletcher-Munsen curve. To the Venturi Formula 2, Formula 4 and Formula 6 introduced earlier, BIC now adds a smaller 2-way model, Formula 1, priced Stateside at $74.95.
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Following up its introduction a year ago of a jumbo power amplifier, Bose now offers a matching preamplifier that marks the company's formal entry in the 4-channel sweepstakes. The new 4401 has four separate channels of preamplification and special rear-panel jacks for connecting two equalizers for Bose 901 speakers. Which means, if you go quadraphonic all the way with Bose, you'll want not one but two model 1801 behemoths (400 watts rms per channel, about $1000 each in the States) to power the system.

But Bose recognizes that you might opt for a more modest amplifier and non-equalized speakers for the rear channels, so there's special provision for equalizing only the front channels and bypassing equalizer circuitry in driving the rear channels. Either way, the preamplifier's tape monitor functions are not pre-empted. The 4401 has jacks and switches for two tape decks and permits cross-dubbing from one recorder to the other. Tone controls and filters can be used, if desired, to process the signal for recording purposes. Also notable is the preamplifier's modular construction with circuitry for the SQ decoder and CD-4 demodulator on plug-in modules which can be replaced with updated circuitry should there be unforeseen new developments on the 4-channel scene. The 4401 carries a Stateside price tag of $499.

While the Bose speakers are unchanged, the 901's pedestal has been restyled with a slender stem and round top. There's also a new "Continental" model identical to the 901 in sound but with a rounded front panel and tweed grille, the reshaped cabinet available in a choice of white or walnut.

A plastic slug that "keys" the cartridge for either stereo or 4-channel operation is featured on a new blank tape cartridge from Columbia, tape subsidiary of CBS. Called "ConvertaQuad," the slug activates the sensing device built into 4-channel cartridge recorders and players. When the slug is in place, the machine will automatically switch to stereo mode. Removing the slug causes the deck to switch to quadraphonic operation. Each blank cartridge in the Columbia line will be fitted with the ConvertaQuad slug, which can be removed or replaced as necessary to key tapes for the desired mode.

Columbia also announces a new 50 minute cartridge, designed to hold one complete LP album with minimum blank space at the end, since CBS' research indicates that virtually no popular recordings on the market are longer than 50 minutes' duration. Columbia's line of blank cartridges now includes 40-, 50-, 80-, and 100-minute lengths, and all will be made in future with a new self-lubricating plastic hub that, according to CBS, is virtually jam-proof.
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The Crown people in Elkhart, Ind., who make jumbo amplifiers and a 10 1/2" reel tape deck, displayed their latest equipment in newly designed walnut cases, instead of the customary metal racks. The new Crown OC-150, billed as a Stereo Output Control Center, is an unusual component designed to fit between the power amplifier and speakers in an elaborate stereo system.

It has two large multi-purpose meters and switching facilities for three pairs of speakers. The meters not only indicate VU (like the meters in a tape recorder) but can be switched to peak-catching mode, electronically detecting signal peaks and "storing" the information so there is time to manually adjust levels.

This also makes it possible for a user to accurately determine the clipping point of an amplifier and note the maximum voltage as indicated by the meters. The 0C-150 will also monitor the output of two additional amplifiers (other than the main amplifier driving the speaker systems). For example, it will monitor the rear channels in a quadraphonic system, comparing their output level with that of the main, front-channel amplifier. Terminals and switches are also provided for driving three stereo headphones of different sensitivity.

Another new Crown item is the UFX2 electronic crossover, a two-channel dividing network that is infinitely variable from 20 Hz to 20,000 Hz and provides 18 dB rolloff per octave. It is intended for use with bi-amplified systems employing separate power amplifiers for bass and treble speakers.

New accessories are on the way from Discwasher, Inc., the Columbia, Manufacturer of record cleaning equipment. The Discorganizer is a solid walnut stand that will hold the Discwasher pad, bottle of fluid and other small items that need to be stored in a handy place next to the record player.

Price of the Discorganizer will be about $6.00 in the States. Another new item is a turntable foundation of high-density polymer resins, finished to look like marble and nearly as heavy. It has eight rubber damping feet, designed to absorb both horizontal and vertical vibrations. The turntable base has two pass-through holes for audio and power cables. It will carry a retail price of about $40.
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Two of Dokorder's three new open-reel tape recorders are 10 1/2" reel models. The 1140-H, Dokorder's top-of-the-line 4-channel model, is styled like a recording console with the tape transport on a sloped panel while the electronics are housed in a rack panel over the console.

Circuitry includes multi-synch switching of the 4-channel recording head for mixing and over-dubbing, and full logic control to prevent tape spillage when switching instantly from rapid-wind into play or record mode. The three-motor, three-head deck will have a Stateside price of $1,199.95.

The second 10 1/2" reel deck, model 1120, also offers three motors and three heads in a choice of two-track or four-track stereo and can be converted at the user's option to either head configuration. U.S. retail price is $649.95.

Latest Dokorder 7" reel model is the 9200, also styled like a console, offering six heads for bidirectional recording and playback in four-track stereo. All functions are electronically controlled with logic IC circuitry, and "automatic memory" is provided as an added fillip for advance programming of selections for playback. Price is $899.95.

Dokorder also has a three-head cassette tape deck that includes separate Dolby circuits for recording and playback, permitting tape/source monitoring of Dolbyized signals. Model designation is MK-60, and Stateside price is $329.95. All four new Dokorders are announced for October-November 1974 availability.

Evidence of the trend toward automatic single-play turntables is Dual's new 601, a lower-cost version of the costly direct-drive model 701 introduced last year.

The 601 employs a high-speed 8-pole synchronous motor and belt drive. Its tone arm features the same twin-gimballed tone arm suspension system of the 701. Stateside price of $270 includes base and dust cover.

Dual's changer line is now headed by the 1229Q. Refinements include low-capacitance wiring to minimize signal loss when playing CD-4 records, and an anti-skating system calibrated for CD-4 styli as well as standard conical and elliptical types. Stateside price of the 1229Q, not including base, is $259.95.

The "step-down" model 1228, priced at $189.95, offers the same four-point gyroscopic tonearm suspension and illuminated strobe speed control. Next in the line is the Dual 1226 at $159.95, while the budget model is the Dual 1225 at $129.95.

Dual also has a new cassette tape deck, its first (und es war eine Katastrophe !!). It is a bidirectional model with automatic reverse and continuous playback. Dolby noise reduction circuitry is included, and there is a built-in oscillator to allow calibration of the circuitry for any tape. Recording bias is switched automatically between standard and chromium dioxide. Known as the 901, the new Dual cassette deck is priced Stateside at $450.

• Anmerkung : Viel zu teuer im Vergleich zu den vielen Japanern für 179.-.

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The first 4-channel product announced by Dynaco is the QSA-300 power amplifier, offering 75 watts per channel (rms) at eight ohms with all four channels driven from 20 to 20,000 Hz. Its four outputs can be strapped, converting it to a stereo amplifier rated at 150 watts per channel at 8 ohms, or 200 watts per channel at 4 ohms. Dynaco says that the built-in strapping circuit delivers such high power into low-impedance loads (below four ohms) that, with this amplifier, several pairs of 8-ohm speakers can be connected for simultaneous operation without limiting power. With four meters included, the QSA-300 will be available factory-assembled at $599.

In kit form, it will be sold without the meters for $399. A kit for adding the four meters is $125 additional. There is also a stereo version of the same amplifier, the Stereo 150, which can be strapped for monophonic use. No meters on this model, which costs $325 factory-assembled, $225 as a kit.

Dynaco also announces a new stereo preamplifier, the PAT-5, that features two inputs for tape with monitoring and dubbing facilities for each and provision for copying from one tape deck to the other. As the all-transistor preamp draws only 12 watts of AC, Dynaco has wired the power switch so it controls only the AC outlets on the back panel while the preamp itself remains on.

In Dynaco's view, leaving the circuitry connected helps drive off moisture and keeps the electrolytic capacitors at operating voltage to eliminate start-up pops and clicks. But, for energy purists, instructions are provided for rewiring the unit for fully off switching.

Dynaco's A-25 loudspeaker now offers improved power handling and greater efficiency, with a new dome tweeter and a modified woofer design. The cabinet is the same, employing a highly damped vent to control the resonance of the system. Finished in walnut, the improved model is known as the A-25XL and carries a $99 price tag. Dynaco's A-10 speaker, while unchanged, is now available in a vinyl-covered walnut grain finish at a saving in cost. The new A-10VW will be priced Stateside at $110 a pair.

The slow pace of CD-4 recording in the Stateside market hasn't deterred customers from buying the costly wide-range cartridges needed for CD-4 playback, according to Herb Horowitz, boss of Empire Scientific Corp.

He offers a new line of cartridges, the Super 4000D series, with frequency response up to 50,000 Hz, spanning not only the audible bandwidth of conventional recordings but a CD-4 disc's high frequency carrier as well. While you need this wide-range performance only for discrete 4-channel, Empire claims that a cartridge made to such tolerances also provides superior performance in conventional stereo.

The 4000D series has a .1 mil diamond tip that Empire calls "4-dimensional," a new shape that hugs the more complex groove cut into CD-4 discs and tracks at less than two grams. The top-of-the-line model, 4000D/III, is rated at 3/4 to 1 1/4 grams tracking force and carries a Stateside list price of $149.95. The 4000D/II, with 5-45,000 Hz frequency response, costs $124.95, while the 4000D/I, at $84.95, lists a frequency response of 10-40,000 Hz.

It's just a year since ESS, a West Coast manufacturer of highly specialized (and costly) speaker systems, unveiled a new tweeter called the Heil air-motion transformer, a totally different loudspeaker construction employing a pleated diaphragm that opens and closes like an accordian to "squeeze" the air instead of pushing it like a cone speaker diaphragm.

What really distinguishes the speaker, says its inventor, physicist Oskar Heil, is the instantaneous acceleration that takes place when air in the folds of the diaphragm is forced through the narrow slits in front of the speaker — it gives the Heil tweeter much shorter "rise time," i.e. improved transient response.

Also, because there are conduction strips inside each fold of the diaphragm, the electrical signal from the amplifier is distributed evenly throughout the magnetic structure instead of traveling, as in a conventional cone, from the voice coil in the center to the outer edges of the diaphragm.

The designer claims that, since the moving force is applied uniformly instead of to a single point (a center voice coil), there is no "ringing" or resonance to color the sound. In the course of a year of explaining and demonstrating the Heil principle, ESS has marketed several hybrid designs pairing the air-motion transformer for midrange and treble frequencies with conventional cone speakers for the bass.

While a fullrange Heil speaker, reportedly under development, is hot yet on the scene, ESS has further refined the tweeter design to make it smaller and less complex so it could be included in lower-cost speaker models. The newest, unveiled during CES, is the ESS amt5 bookshelf, its tweeter a 16-fold miniaturized diaphragm mounted in a lightweight fiber holder, with the slotted openings in a metal front plate that ESS calls a "power ring".

The new miniaturized air-motion transformer tweeter handles frequencies above 1,500 Hz, while a 12-in. acoustic suspension cone woofer covers frequencies below the crossover point. The two-way bookshelf system, with sculptured black fabric grill, has a Stateside retail price of $189.

In addition to full-logic circuitry, which enhances front/rear and left/right separation of SQ matrix-ed records, a new quadraphonic receiver announced by Fisher, model 634, will offer a circuit called "Phase Logic" claiming to improve left/right separation in the rear channels.

Rated at 140 watts (4 x 35) per channel rms with all four channels driven at eight ohms from 20 to 22,000 Hz, the 634 has a total of six front-panel meters for calibrating levels, as well as the customary signal strength and center-channel tuning functions. Backing up the 634 in this new series will be four lower-powered quadraphonic receivers (534, 434, 334 and 234) and two stereo models (222 and 122) at modest prices.

The top four models will include built-in CD-4 demodulator. It will be spring 1975, however, before the 634 is generally available. Meanwhile, Fisher offers three 4-channel receivers in its "Studio Standard" series, models 514, 414 and 314, that have built-in CD-4.

Previewed at the Winter CES (Off Duty, May 1974), they are now being delivered and the top-of-the-line 514 (Stateside price $749) is on the way to overseas exchanges.

Fisher also has a big new entry in the mass-market audio field with a line of popular priced (also sehr sehr preiswert) sound systems. There are four basic receivers - two stereo and two quadraphonic — to which a choice of three speaker models is added. Other options are built-in cartridge tape player and/or record changer. Called "MusiCenters," the Fisher modular systems can thus be fashioned into 21 different combinations.

(Continued next month)

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