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W-6M 70-Watt Amplifier

W-6M 70-Watt Amplifier


  • Metered balance circuit—variable damping
  • New silicon-diode rectifiers
  • Excellent stability and power supply regulation
  • Plenty of reserve power for program material that demands it

The W-6M Amplifier with its many fine design features has been enthusiastically accepted by the serious audiophile as one of the finest units available on the market. The W-6M with 70 watts output will give you a truly fine performance at any power level and will drive any of the finer speaker systems available today. It will also allow you to obtain the full dynamic range of your favorite recordings or tapes. The question has often been raised, "Why do I need 70 watts?" A logical one since in many cases 10 watts may be adequate. The answer is that the present upward trend in amplifier power is necessary to keep abreast of other recent advancements in the audio art. As loudspeaker systems have been improved in bass response, their efficiencies have, in general, been reduced; this means more amplifier power for the same acoustic output from the speaker. Another important factor is the ever-increasing dynamic range of LP records and pre-recorded tapes, approaching that found in the concert hall. Even though the full rated power output may be demanded only on the loudest musical passages and transients, it is extremely important that the amplifier be capable of supplying the reserve power with negligible harmonic and intermodulation distortion.

In the design of the W-6M silicon-diode rectifiers were selected since they have no filament, to cause unnecessary heat, or burn out. They are also noted for their very long life, and yet, are smaller than a house fuse. A heavy-duty transformer, with the latter, permits extremely good power supply regulation. The output circuit employs 6550 tubes with special-design Peerless output transformer for maximum stability at all power levels, and a variable damping control for optimum performance with any speaker system. A quick-change plug selects 4, 8, and 16 ohm or 70 volt output and the correct feedback resistance. A built-in meter indicates when output tubes are in proper balance, eliminating the need for an external meter. This meter also provides a means of spot checking from time to time to note condition of output tubes indicating whether or not best possible performance is being obtained.

Attractive shield prevents tube breakage and accidental burns. Top quality components used throughout. Proper layout of chassis assures ease of assembly (by eliminating those cramped and difficult places to get at). Frequency response at 1 watt is within ± 1 db from 5 CPS to 80 kc with controlled rolloff above 100 kc. Harmonic distortion is below 2% 20 to 20,000 CPS and IM distortion is below 1% 60 and 6,000 CPS at full output assuring quiet performance.

In addition to the fine specifications shown above, the W-6M is handsomely designed, making it a pleasure to display. Components used in the W-6M have generous safety margins so that they are operating well below their maximum ratings. Your assurance of years of dependable trouble free operation.

Specifications—Power Output: 70 watts. Frequency Response at 1 watt: ± 1 db from 5 to 80,000 KC with controlled rolloff above 100 KC. Harmonic Distortion at 70 watts: below 2%, 20 to 20,000 CPS. Intermodulation Distortion at 70 watts: Below 1%, 60 and 6,000 cps. Hum and Noise Level: 88 db below full output. Damping Factor: variable, 0.5 to -10. Input voltage for 70 watts Output: 1 volt. Tube complement: 1-12AU7, 1-12AX7, 1-12BH7, 2-6550. Output Transformer: Peerless—special design. Output taps at 6, 8 and 16 ohms, and 70 volts. Dimensions: 11-7/8" D. x 9-1/16" H. x 14-¼" W. Shipping Weight: 50 lbs.

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