The new tests will expose if amplifiers really deliver the power they promise.
The Federal Trade Commission has tightened its grip on the home audio industry with a revised “Amplifier Rule.”
Effective since August 2024, requires more thorough testing for amplifier power output claims. Overall, this could reveal differences between what the brand advertised and the amp’s actual performance.
What’s New in the 2024 Amplifier Rule?
The FTC’s updates mostly focus on bringing in tougher rules for measuring and reporting amplifier power output.
These changes make sure manufacturers use reliable methods for their power output claims, which could address issues that could mislead buyers. It’s especially useful for online shoppers who can’t test amplifiers in person before making a purchase.
Here’s what’s changing:
- Distortion Limits: After running at full power for five minutes, amplifiers must stay under 1% total harmonic distortion plus noise (THD+N) from 20Hz to 20kHz.
- Testing Conditions: Testing must now occur at an air temperature of at least 77°F (25°C) for more consistent results.
- Preconditioning Requirement: Before testing, amplifiers need to warm up to more accurately simulate real-world conditions. For this, they must run at 1/8 of their rated power for one hour using an 8-ohm load.
- Frequency Range Testing: The old rules only tested at 1kHz, which sometimes led to overstated performance. Now, testing must include both 20Hz and 20kHz, giving a more complete picture of an amp’s capabilities.
- Multichannel Amplifiers: Front-left and front-right channels must be fully powered during testing. Self-powered subwoofers, on the other hand, follow different rules for their frequency range.
Impact on Manufacturers
Previously, manufacturers had considerable leeway in their test conditions. However, this often resulted in very different results for the same amplifier model.
But now, manufacturers must now follow specific guidelines when advertising their products’ power output.
Such guidelines include:
- FTC Power Output Rating: If they meet the new rules, power output claims must be labeled “FTC Power Output Rating.”
- Optional Disclosures: Manufacturers don’t have to show the maximum power output. But, if they offer extra power output info, it must be labeled “This rating was not tested under the FTC standard,” and be less noticeable than the FTC rating.
- Clarifications: Manufacturers cannot disclose testing conditions using footnotes, asterisks, or similar notations. Basically, no more hiding behind fine print!
These new regulations aim to expose exaggerated claims. So, many amplifiers that passed the old rules may now struggle to meet the stricter standards.
For example, amplifiers must now show consistent performance across the full frequency range while staying within a 1% THD+N limit. This could be a problem for models that previously focused on mid-range performance.
Concerns and Criticism
The FTC received 550 unique comments in response to the initial proposal, with overwhelming support for retaining the rule. However, not everyone is happy.
Some industry groups, like the Consumer Technology Association (CTA), have raised concerns.
For one, some manufacturers worry that the 1% THD+N limit could exclude many amplifiers, especially those using vacuum tubes.
Another issue raised is the 20Hz to 20kHz testing range. Though most amplifiers can handle the full range, critics say these strict rules may not fit some amplifiers, especially those not meant for full-range audio.
Lastly, some in the industry fear the rule’s focus on the full frequency range may overemphasize distortion from power supply hum and noise.
The Consumer Technology Association (CTA) suggested testing at 1kHz, where distortion is less noticeable. But the FTC said no, saying a wider range is needed to capture real-world distortion.
In response to industry feedback, the FTC did make some adjustments.
For example, they changed the wording for Optional Disclosures to “This rating was not tested under the FTC standard” instead of “This rating does not meet the FTC standard.” This change aims to avoid criticizing international standards that manufacturers might use in their optional disclosures.
Still, the FTC thinks that the benefits of being clearer outweigh potential problems for manufacturers. They’ve certified that the amendments won’t have a significant economic impact on a substantial number of small entities.