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Bronze Member Username: MrgoochNj Post Number: 15 Registered: Sep-05 | Concerning a vintage receiver: Power Rating: RMS power ratings are 4-5 time greater than todays power ratings. Example: 60WPC RMS power equals approximately 240WPC under todays power ratings. |
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Silver Member Username: Devils_advocatePost Number: 490 Registered: Jul-05 | Depends on what specifically you are asking. There are a number of bad eggs which heavily inflate their wattage through a variety of semantics, eg wattage into a 6/4 ohm load, 2 channels driven instead of 5, or power delivered at 1kHz instead of 20Hz-20kHz. Then there are others manufacturers that do rate theirs conservatively into 8ohms, all channels driven, 20Hz-20kHz, like Harman Kardon. To keep track of the good eggs and bad eggs you might check measurements off Sound and Vision or other such mags. Now then, you might want to find out what your receiver actually puts out before moving forward. But, assuming it is of good quality, it could probably outperform a $199, 7 channel, 15 pound Sony receiver rated at 150 watts. OTOH it probably won't outperform a $1099, 7 channel, 45 pound, Harman Kardon receiver rated for 100wpc. PS: You might also keep in mind that there is more to an amplifier than how much wattage it puts out. In addition, doubling the wattage only yields a 3 decibel increase. |
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Gold Member Username: Jan_b_vigneDallas, TX Post Number: 6029 Registered: May-04 | The FTC has not relaxed its provisions for measuring RMS power output since the 1970's when they were tightened in an attempt to make ridicuous claims of instantaneous peak power for one channel driven at 1 kHz a memory. Test bench RMS power is still test bench RMS power. There are however two problems with RMS power ratings. 1) They are never taken in a manner that actually simulates how the product will be used. A load resistor and sinewaves do not equate to a loudspeaker and music. 2) The manufacturers have found ways to sell products that ignore the FTC regulations when marketing receivers. This is mostly restricted to HTIB systems where a $400, 1200 watt system is sold as a reality. The problem ammounts mostly to the manufacturers' ability to design for the test and not for the real world. Cooling fans and impedance selection switches allow a manufacturer to fudge what the receiver can actually manage to accomplish when faced with a loudspeaker that fights back while reproducing more than one frequency at more than one amplitude. Power supplies have been made less expensively than before, but that has been happening since the 1960's. Sony switched to a series hook up for their A-B speaker switching in the 1960's in order to maintain a high enough impedance load for what was then considered their inadequately powered receivers of the day. During the 1970's & '80's most receivers could not drive four Ohm loads due to decreased power supply functions. If anything, in the late 1970's, NAD made the situation worse when they began quoting peak power numbers once again. If you pick up a 1960's, 1980's and a current stereo receiver, the weight difference is astounding. While significant reductions have been made in the areas of digital tuners and IC technology, the main difference lies in the power supplies which are the heart of any piece of electronics. With the addition of more channels for HT use, the amount of power supply capacity has consistently been reduced with a concomitant reduction in real world performance. Many of these recievers are literally sucking voltage and current directly out of the wall socket in order to reproduce large scale signals and falling flat when the next signal comes along. This is most apparent in the receiver market where a 100 watt RMS rating means little when it cannot driver a low impedance load nor quickly recover from a large scale transient signal. The high end market of separate amplifers and integrateds does not suffer the same amount of dishonesty as the mass market brands inflict. Some mass market manufacturers are far more genuine with what they produce. You can usually spot which manufacturer is being honorable with their specifications by looking at the price tags. If it looks too good to be true, it probably is. As your statement is written, I strongly disagree. 60 watts RMS is still 60 watts RMS. On a a test bench. What that 60 watts will acomplish in the real world has changed, and not for the better in most cases. But, no, 60 watts RMS does not equate to 240 watts RMS. |
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Gold Member Username: Jan_b_vigneDallas, TX Post Number: 6033 Registered: May-04 | http://www.audioholics.com/techtips/audioprinciples/amplifiers/receiverpower.php |