FTC Power Amplifier Rule

[D Murphy]

The Federal Trade Commission will be publishing a Notice of Proposed Rulemaking in the Federal Register in a day or two. The Notice will seek comment on proposed amendments to the Rule that may affect how power ratings for multichannel receivers must be measured. Currently, such AVR's need only publish power and distortion specs for 2-channel operation. The new Rulemaking will revisit this issue. The press release concerning the upcoming Federal Register Notice is pretty foggy except for the recommendation that THD must be lower than .1% at the rated power. That will prove controversial to say the least. Currently there is no cap on distortion--you just have to disclose what it is. Here's the press release, which asks for comments on:

• "whether the Commission should amend the Rule to simplify power output measures by standardizing the test parameters used by amplifier sellers as follows: a load impedance of 8 ohms, a power band of 20 Hz to 20 kHz, and a THD limit of less than 0.1%; and
• the parameters of consumers’ normal use of multichannel home theater amplifiers."

I have no idea what they mean by "the parameters of ...normal use..." But we'll know shortly. I'll post a link to the Federal Register Notice when it's published.

 

[3db]

The Federal Trade Commission will be publishing a Notice of Proposed Rulemaking in the Federal Register in a day or two. The Notice will seek comment on proposed amendments to the Rule that may affect how power ratings for multichannel receivers must be measured. Currently, such AVR's need only publish power and distortion specs for 2-channel operation. The new Rulemaking will revisit this issue. The press release concerning the upcoming Federal Register Notice is pretty foggy except for the recommendation that THD must be lower than .1% at the rated power. That will prove controversial to say the least. Currently there is no cap on distortion--you just have to disclose what it is. Here's the press release, which asks for comments on:

• "whether the Commission should amend the Rule to simplify power output measures by standardizing the test parameters used by amplifier sellers as follows: a load impedance of 8 ohms, a power band of 20 Hz to 20 kHz, and a THD limit of less than 0.1%; and
• the parameters of consumers’ normal use of multichannel home theater amplifiers."

I have no idea what they mean by "the parameters of ...normal use..." But we'll know shortly. I'll post a link to the Federal Register Notice when it's published.

Thanks Dennis. Finally, another small incremental step in the audio industry towards standardization.

 

[fmw]

The Federal Trade Commission will be publishing a Notice of Proposed Rulemaking in the Federal Register in a day or two. The Notice will seek comment on proposed amendments to the Rule that may affect how power ratings for multichannel receivers must be measured. Currently, such AVR's need only publish power and distortion specs for 2-channel operation. The new Rulemaking will revisit this issue. The press release concerning the upcoming Federal Register Notice is pretty foggy except for the recommendation that THD must be lower than .1% at the rated power. That will prove controversial to say the least. Currently there is no cap on distortion--you just have to disclose what it is. Here's the press release, which asks for comments on:

• "whether the Commission should amend the Rule to simplify power output measures by standardizing the test parameters used by amplifier sellers as follows: a load impedance of 8 ohms, a power band of 20 Hz to 20 kHz, and a THD limit of less than 0.1%; and
• the parameters of consumers’ normal use of multichannel home theater amplifiers."

I have no idea what they mean by "the parameters of ...normal use..." But we'll know shortly. I'll post a link to the Federal Register Notice when it's published.

1/10 of a percent distortion eliminates most if not all tube amps. That assumes there are any tube AVR's. I don't know. 1% THD isn't audible. It seems like an overly conservative parameter.

 

[D Murphy]

1/10 of a percent distortion eliminates most if not all tube amps. That assumes there are any tube AVR's. I don't know. 1% THD isn't audible. It seems like an overly conservative parameter.

We'll have to see what the Federal Register Notice really says. I was expecting it to be published last week, but it's still MIA.