如何强制macOS将aptX或AAC编解码器用于蓝牙耳机
The Bluetooth codec your headphones use significantly impacts sound quality. Unfortunately, macOS sometimes uses the subpar SBC codec instead of the superior aptX or AAC codecs. Here’s how to force macOS to use one of those instead.
耳机使用的蓝牙编解码器会严重影响音质。 不幸的是，macOS有时会使用低于标准的SBC编解码器，而不是高级aptX或AAC编解码器。 这是强制macOS使用其中之一的方法。
什么是蓝牙编解码器？ (What is a Bluetooth Codec?)
The word “codec” is short for “coder-decoder,” which is precisely what a codec does. In this case, the codec is used to compress the audio file on one end (code) and decompress it on the other (decode). This allows the file to be transmitted quickly. Some codecs are better than others at compressing audio without reducing its quality, which is why choosing the right one is essential.
“编解码器”一词是“编解码器”的缩写，这正是编解码器的作用。 在这种情况下，编解码器用于在一端压缩音频文件(代码)，在另一端解压缩音频文件(解码)。 这样可以快速传输文件。 一些编解码器在压缩音频而不降低音频质量方面比其他编解码器更好，这就是为什么选择正确的编解码器至关重要。
SBC is the codec that macOS sometimes defaults to, whereas aptX and AAC offer better sound quality. All three codecs compress the audio before sending it to your headphones, but aptX and AAC do so without a dramatic impact on the overall audio quality. SBC was designed to be efficient and ensure compatibility rather than to offer the best possible sound quality. Latency is also a consideration with SBC, and audio lag is noticeable when watching video content. Neither aptX or AAC exhibit this behavior.
SBC是macOS有时默认使用的编解码器，而aptX和AAC提供更好的声音质量。 这三个编解码器都先压缩音频，然后再将其发送到耳机，但aptX和AAC这样做不会对总体音频质量产生重大影响。 SBC旨在有效并确保兼容性，而不是提供最佳的声音质量。 延迟也是SBC的考虑因素，在观看视频内容时音频延迟会很明显。 aptX或AAC均未显示此行为。
If you want to learn more about how aptX and AAC work, we have a good primer on the subject.
如果您想了解有关aptX和AAC如何工作的更多信息，我们将为您提供一个很好的入门基础 。
In short, aptX promises “CD-like” sound quality, which is something SBC cannot offer. Likewise, AAC’s improved compression algorithms allow for better sound quality, despite its lower maximum bitrate of 250Kbps when compared to the 328Kbps of SBC. The aptX codec, however, bests both at 352 Kbps.
简而言之，aptX承诺提供“类CD”的音质，这是SBC无法提供的。 同样，AAC改进的压缩算法可提供更好的声音质量，尽管与SBC的328Kbps相比，其最大比特率较低，仅为250Kbps。 但是，aptX编解码器的最佳速度为352 Kbps。
Unfortunately, not all Bluetooth headphones support aptX or AAC, although most of the more recent models do. If you do force your Mac to use either codec, but your headphones don’t support them, don’t worry—it will automatically switch to SBC instead.
不幸的是，尽管大多数最新型号都支持aptX或AAC，但并不是所有的蓝牙耳机都支持aptX或AAC。 如果您确实强迫Mac使用任何一种编解码器，但是您的耳机不支持它们，请放心-它会自动切换到SBC。
如何检查使用哪个编解码器 (How to Check Which Codec is In Use)
To see which codec is in use, connect your Bluetooth headphones to your Mac and play some audio. Hold down the Option key and click the “Bluetooth” icon in the menu bar.
要查看使用的编解码器，请将您的蓝牙耳机连接到Mac并播放一些音频。 按住Option键，然后单击菜单栏中的“蓝牙”图标。
Highlight your headphones and note the Active Codec.
突出显示您的耳机并记下活动编解码器。
This is the codec that is currently in use. You’re fine if it’s aptX or AAC; otherwise, read on.
这是当前正在使用的编解码器。 如果是aptX或AAC，就可以了； 否则，请继续阅读。
如何强制aptX或AAC (How to Force aptX or AAC)
Download Additional Tools for Xcode from the Apple Developer site. You will need to create a free Apple Developer account to do so. Once it’s downloaded, double-click the “Additional Tools” DMG file to mount it.
从Apple Developer网站下载Xcode的其他工具 。 您需要创建一个免费的Apple Developer帐户。 下载完成后，双击“其他工具” DMG文件进行安装。
Double-click “Additional Tools” on your desktop.
双击桌面上的“其他工具”。
Double-click the “Hardware” folder.
双击“硬件”文件夹。
Drag “Bluetooth Explorer.app” to your Applications folder.
将“ Bluetooth Explorer.app”拖到“应用程序”文件夹中。
Double-click the “Bluetooth Explorer” app and click “Tools > Audio Options” in the menu bar.
双击“ Bluetooth Explorer”应用程序，然后在菜单栏中单击“工具>音频选项”。
Check the “Force use of aptX” and “Enable AAC” boxes. Make sure the “Disable AAC” and “Disable aptX” boxes are unchecked. (Yeah, for some reason the app will allow you to check both “enable” and “disable” boxes.)
选中“强制使用aptX”和“启用AAC”框。 确保未选中“禁用AAC”和“禁用aptX”框。 (是的，由于某种原因，该应用程序将允许您同时选中“启用”和“禁用”框。)
Click the “Close” button to save the changes.
单击“关闭”按钮以保存更改。
Disconnect and reconnect your headphones, and then confirm that they are now using the aptX or AAC codecs as described earlier. If they are, you should notice an improvement in sound quality. If not, it might be time to treat yourself to some new headphones.
断开并重新连接您的耳机，然后确认它们现在正在使用aptX或AAC编解码器，如前所述。 如果是这样，您应该注意到音质有所改善。 如果不是的话，也许是时候使用一些新耳机了 。