Audioholics Petition to Reopen FTC Final Amplifier Rule of 2024

Call to action to our readers and Youtube audience to ask the FTC to reopen their final Amplifier Ruling of August 2024 (16 CFR Part 432)

This petition urges readers and our YouTube audience to ask the FTC to reconsider its Final Amplifier Ruling of August 2024 (16 CFR Part 432). The ruling affects how power output claims for home audio amplifiers are regulated, aiming to help consumers make informed comparisons. Unlike previous guidelines, the new ruling applies to ALL audio products, including powered speakers, soundbars and subwoofers, rather than only to audio amplifiers and AV receivers. The ruling also does not specify testing requirements for more than two channels simultaneously for multi-channel amplifiers, nor does it mandate 4-ohm power ratings. Additionally, the rule applies to closed systems, such as powered speakers and subwoofers, regardless of operational bandwidth, impedance or achievable clean output SPL. This rule is also retroactive, applying to products manufactured before the FTC Final Rule of 2024, which could have profound implications for electronics manufacturers.

Given the challenges and potential consumer confusion arising from the 2024 FTC Amplifier Ruling, we urge the FTC to reopen the proceeding and seek comments on alternative testing procedures and specification requirements that better reflect real-world use. Your support is crucial in ensuring accurate and reliable power output claims for audio amplifiers and powered speaker systems.

Comments on CTA’s petition are due to the FTC by November 8, 2024. To submit comments, visit the FTC Comment Page.

History of the FTC Amplifier Rule

The FTC Amplifier Rule, originally established in 1974, was created to regulate power output claims for home audio amplifiers, ensuring that consumers could make informed comparisons amidst misleading advertisements. These advertisements often used inconsistent testing methods, leading to confusion. In 2020, the FTC sought public feedback for possible updates, and by July 2022, proposed standardized testing conditions to better align with modern multichannel home theater amplifiers. The final rule enforces uniform testing, requires clearer disclosures, and formalizes guidance on multichannel amplifiers

Are the test conditions really feasible and representative of how consumers use audio amplifiers with real program material for music and cinema applications? That is what we plan on exploring in this article as it relates to 16 CFR Part 432 Final FTC Amplifier Ruling effective August,12^th, 2024.

2000 FTC Mandate Removal Sparked Inflated Power Claims?

In 2000, the FTC removed the mandate from “media advertising” that pertained to 3 parameters for rating amplifier power: load impedance, rated power band or frequency response, and total harmonic distortion (THD). However, this mandate remained in effect for power claims in manufacturer specification sheets. However, many manufacturers took it upon themselves to inflate power ratings in marketing materials displayed on the show floor or in advertisements. This could have largely been the catalyst that wreaked havoc in the industry and instigated the ‘Truth In Power’ movement that we’ve written about a multitude of times such as Has the FTC Failed Consumer Audio? The fallout was apparent at big box stores particularly related to HTiB systems claiming ridiculous 1kwatt+ total power output as a sum of the per channel ratings rather than a measure of ALL of the channels driven simultaneously at a specific load impedance, bandwidth and distortion level.

Editorial Note by Dennis Murphy:
The FTC mandate removal was done in response to pressure from the Office of Management & Budget (OMB) to reduce disclosure burdens in the media.  However, this wasn't why adherence to the Rule's basic requirements deteriorated.   Any power output claim that appeared in advertising had to be based on continuous power, and the power band and maximum THD still had to be disclosed in spec sheets. If companies had adhered to the revised Rule, nothing would have changed other than the relaxation of disclosure requirement in advertising.  Companies still had to adhere to the specified standard operating conditions. The breakdown in Rule compliance was instead due to the lack of enforcement by the Commission and the growing market share of multi-channel amplifiers, which weren't explicitly covered by the Rule. 

Audioholics Lobby to Save the FTC Amplifier Ruling

In 2020, an unprecedented event occurred in the history of consumer audio when the FTC proposed eliminating the amplifier rule, which had been in place since 1974, despite being loosely enforced. We followed up with an article related to the FTC's proposal, urging our readers and YouTube subscribers to appeal to the FTC to maintain the rule, with the possibility of expanding it, as outlined below.

Visit the FTC’s "Trade Regulation Rule..." page (linked again below) then access public comments page (shown above) by clicking "Comment Now!" button in the upper-right of the page. Feel free to copy and paste the following comment and let regulators know that consumers would benefit from the following refinement in the amplifier rule. 

“I wish the FTC to save and enforce the Amplifier Rule but also amend the rule for today’s multi-channel amplifier products with the following measurement:

3CH driven, full power bandwidth, 8 ohms, at specified % THD+N (max 0.1% THD+N) with remaining channels driven at 1/8th power.”

Click here to leave your comment by February 16th, 2021: Trade Regulation Rule Relating to Power Output Claims for Amplifiers Utilized in Home Entertainment Products

Our efforts to bring awareness to this issue, along with the support of our dedicated readership and viewers, played a significant role in prompting a flood of feedback to the FTC, which received 1,130 comments and documented 550 unique responses from various stakeholders, including amplifier and speaker manufacturers, sellers, purchasers, engineers, and journalists in the audio field. Notably, all but one commenter supported retaining the rule, emphasizing its continued necessity. Despite this support, some recommended specific amendments, particularly regarding the need for uniform power band, load impedance, and THD limits to prevent the manipulation of test conditions.

New FTC Ruling as of August 2024

16 CFR Part 432 , June 5, 2024

The new ruling which the FTC deems as “Final Amendments” does NOT require amplifier manufacturers to disclose maximum power output—but those that do must follow the new standards.

A serious concern of the new amplifier ruling is the time duration specified for rating full power, something which was always a bit vague or at least loosely enforced in prior FTC rulings. After the input signal has been continuously applied at full rated power for at least five minutes, the amplifier needs to be able to function:

 "at any power level from 250mW to the rated power at ALL frequencies within the rated power band of 20Hz to 20kHz without exceeding 1.0% of total harmonic distortion plus noise (THD+N) at an impedance of 8 ohms."

For amplifiers used in self-powered subwoofers in subwoofer-satellite speaker systems (which have separate amplifiers for different frequencies), the rule ensures that the subwoofer's amplifier provides a consistent power level across its intended frequency range, using the same THD+N and impedance conditions regardless if the loudspeaker impedance is lower than 8-ohms.

The rule also defines "rated power" as the minimum continuous power output, measured in watts per channel, for amplifiers designed to drive two or more channels at the same time. For multi-channel amplifiers, the left and right front channels (used in stereo systems) must be tested. However, in self-powered systems like subwoofer-satellite setups, only channels that handle the same frequency range need to be tested together.

This updated regulation is claimed to help consumers by ensuring accurate, comparable information about amplifier performance, avoiding misleading power output claims, and promoting consistency across different devices. But is it realistic to apply "one test to rule them all", regardless if it's a power amplifier or a powered loudspeaker device?

Watt Has Changed with the new FTC Amplifier Ruling of 2024?

The latest revision of the 2024 FTC Rule introduces a significant update by removing the flexibility for manufacturers to specify different frequency bandwidths and distortion levels when claiming power output. Previously, manufacturers could choose these parameters and disclose them accordingly, allowing power output to be advertised across a range of specified load impedances, bandwidths and distortion levels. This created issues in advertising, as the disclosed information was often omitted or unclear, making it difficult for consumers to compare wattage claims accurately.

Under the new 2024 Rule, the power output must now be measured and reported with a fixed bandwidth of 20 Hz to 20 kHz, and the total harmonic distortion (THD) at the rated power must NOT exceed 1%. Sellers are still permitted to specify a lower distortion level if desired, but claims based on higher distortion levels or narrower bandwidths are no longer acceptable, even if such parameters are disclosed.

The updated Rule also formally incorporates the requirements for testing multi-channel amplifiers into the regulations. Previously, these guidelines were only outlined in a Commission directive. Overall, the most significant change is the elimination of power output claims that rely on higher distortion levels or restricted frequency bandwidths, ensuring more standardized and reliable power ratings for consumers.

So Watt’s the Problem with the New FTC Amplifier Rule of 2024?

To start with, under the new FTC “Final Amplifier Rule”, the FTC has applied this to ALL audio products including closed systems like powered speakers and subwoofers rather than just focusing on audio amplifiers and receivers. The prior FTC rule, which dates back to as early as 1990, allowed for powered speakers, enabling the amplifier to be power-specified based on the impedance for which it was designed, rather than fixing it at 8 ohms in all circumstances, as required by the 2024 FTC Amplifier Rule.

Essentially, the new FTC rule aims to impose a single test method on the entire category of audio amplifiers covered by the regulation, from smart speakers to AV receivers. 

That’s a mistake! 

In 2020, we asked the FTC to address “today’s multi-channel audio amplifier products.” We do not believe the FTC had all the information it needed on the differences in amplifier types and design approaches when it issued the final rule.  Providing a common baseline for understanding power claims is critical, but not when that baseline misses the way that this equipment is used.  For example, few consumers would ever ask their amplifiers to produce a sustained, constant tone at full power for a period of minutes.  As a result, many AV receivers don’t include the heatsink area necessary to do that due to space constraints, high channel counts, and heat from HDMI and DSP circuits. Running sustained tones at full power with at least two channels driven can thus trigger fault protection or current limiting, as these conditions stress the amplifier in a way that typical real-world use does not. Moreover, this ruling does not necessarily test the true limits of a multi-channel amp's power supply, as it does not specify how to test more than two channels at a time. Additionally, there is no requirement to specify 4-ohm power ratings, which would provide consumers with invaluable information, since many multi-driver loudspeaker systems are rated at 4-ohms and can enable amplifiers to provide more power where they are limited by maximum voltage rather than current.

Class D amplifiers are gradually replacing class AB amplifiers for  their higher efficiency. These amplifiers have a filter capacitor connected directly across the output to remove ultra-sonic switching noise. These capacitors also absorb a fraction of energy at 20Khz, which they are rated to do under real world conditions, but if stressed by a sustained 20KHz full power tone may over heat or need to be up-rated, needlessly increasing cost and physical size.  amplifiers protect against this by shutting down when a continuous high-power high-frequency tone is detected. Such conditions normally do NOT occur during real-world music or movie program material. This useful and intentional protection can put these amplifiers at a significant disadvantage compared to traditional Class AB amplifiers when tested at the upper frequency range, particularly at 20 kHz for a full five minute duration. As a result, such amplifier designs may be significantly derated in power, despite the fact that many of these designs can potentially offer more dynamic headroom and higher sustained output power than their less efficient Class AB counterparts when multiple channels are driven. Even most Class AB designs are usually limited in power above 10KHz. This rule will result in the majority of amplifiers simply being rated for the maximum power they can sustain at 20KHz, while quite ironically, this is the frequency band that demands the least power in real-world use!

Watt About Powered Speakers?

Powered speakers and subwoofers are considered closed systems and in our opinion, rating amplifier power is meaningless since the actual SPL output of such products is dependent on system efficiency and driver sensitivity. In an active speaker/subwoofer, the amplifier only needs to be as capable of delivering power as the voice coil is capable of taking it. What instead should be rated for such loudspeaker products is system bandwidth, and max SPL at rated distortion. More work needs to be done here to perhaps align with the efforts of the Consumer Technology Association (CTA) who commented extensively during the rule making process on the need to reconsider the proposed standard test conditions as well as the required and optional disclosures.

There is another issue with the FTC Amplifier Rule, too.  When the FTC adopted the Rule, it did so without taking into account normal product design cycles, and simply made the Rule effective as of August 12, 2024—and FTC staff have suggested that the rule applies to ALL equipment as of that date, even gear that was designed, tested, or manufactured before that date.  Without a revision to this new FTC Amplifier Rule, what will happen to amplifiers and powered speakers designed or manufactured before August 12, 2024? Are manufacturers of such products expected to bear the expense of retesting and/or redesigning packaging to comply with the new ruling? Should sellers have to go through their warehouses, opening boxes and swapping out spec sheets?  Are publishers required to retest these products according to the new FTC mandate? From both a legal and practical standpoint, we believe the new FTC ruling should NOT apply to products manufactured and tested before the August 12, 2024, mandate. The CTA has filed a petition seeking clarification on this point, and comments are due November 8, 2024. 

Editorial Note from Simon Ashton from Audiosmile
It is difficult to devise of a well-balanced solution for active speakers. In my opinion, there is value in an amplifier having output that can exceed a voice coils long term RMS power rating in order to reproduce dynamic music passages. Loudspeaker distortion levels vary so widely with frequency that it would be unrepresentative to define it with a single figure. Personally, I would suggest an exemption that allows active speaker amplifiers to be rated at the load impedance of the drivers they are paired with. All channels should be driven simultaneously (as we do not operate each driver individually), and with the bandwidth limiting filters (crossovers) they are paired with in real operation. The output power of each band-limited amplifier channel would be summed to give a total figure for the speaker. In all cases, not only for active speakers, I would like to see a power rating use a simultaneous broad-band stimulus that has equal power per octave (in practice this means pink noise or multi-tone, but not a sweep). This is representative of real-world use, which I believe is most likely the intention of the FTC by specifying a 20Hz-20KHz bandwidth, but unfortunately, they miss the mark by use of a linear amplitude sweep.

Watt Does Audioholics Propose?

1. In light of the information, we have presented above, which reflects the real world challenges of testing to the FTC’s new standard, as well as the confusion it is likely to cause consumers, we believe it is prudent that the FTC reopen the Amplifier Rule proceeding and seek comment on an alternative testing procedure that better reflects real world use.

2. The FTC should establish, either through rulemaking, or a formal staff opinion, an exemption that allows active speaker amplifiers to be rated at the load impedance of the drivers they are paired with.

3. We support CTA’s petition seeking to clarify the Commission’s application of the amended Trade Regulation Rule Relating to Power Output Claims for Amplifiers Utilized in Home Entertainment Products to products designed, tested, and manufactured before the amended Rule’s August 12, 2024 effective date.

4. We also support CTA’s request for a stay of enforcement until the Commission has addressed the issues raised by this petition.

How to Submit Comments to the FTC

Comments on CTA’s petition are due to the FTC by November 8, 2024.

To submit comments, visit the FTC Comment Page. You may attach your comments as a PDF or Word document, or enter them into the provided text box. 

Please mention that you would like this rule to be reopened to consider the technical issues raised by Audioholics.com and the CTA in an effort to more accurately rate amplifier power and the maximum SPL performance of powered loudspeaker systems.

You  can also feel free to reach out to: Hong Park, hpark@FTC.gov