Audio quality via a Bluetooth device can be a great mystery, partly because Bluetooth only mandates in its basic audio standard, A2DP (Advanced Audio Distribution Profile), a low-quality audio encoding algorithm. An audio encoder takes a data stream and transforms it into whatever the best or agreed-upon quality both sides can take, often limited by the particular chips on each device and bandwidth available.
That means that the lowest-common denominator may prevail, even when both the sending and receiving devices have a variety of higher-quality options available that don't match up or aren't correctly invoked.
Unfortunately, the only solution in most cases is to switch to a USB-based headset or USB mic and headphone combination. That ensures the best quality audio is used on your Mac. Back in September 2000, Apple changed from a purely proprietary operating system, Mac OS 9, to a BSD Unix-based operating system, Darwin.It was the birth of OS X. Now, almost 16 years later, Apple.
Depending on a host of factors, both a Bluetooth streaming device (sending or receiving audio) and a Mac may agree on an encoder that makes music sound like it's playing over a landline telephone call.
That shouldn't happen, because iPhones, iPads, and Macs have offered high-quality encoders for many years that are compatible with a wide range of Bluetooth audio equipment from third parties, as well as Apple and Beats hardware. But we've heard from readers and found discussed repeatedly online problems getting the best results on a Mac. This happened in my house just the other day, when my trombone-playing older kid was having a Bluetooth mic peak out—the sound overwhelmed the mic—when he was trying to record himself.
The answer is complex. So much so that someone with the handle ValdikSS had to devote thousands of words in a well-illustrated article at Habr to do justice to the details. Confederate express mac os.
The long and the short is that some integrated devices that couple a mic with a speaker or earphones—as in earbuds, headphones with mic input, a headset with a projecting mic, or a speakerphone—can force audio quality way down when paired with a Mac and with some other hosts.
As ValdikSS notes, this duplex mode of sending and transmitting simultaneously is a problem. 'When this mode is used, both the voice from the microphone and the audio are transmitted to the headphones with the same quality…Unfortunately, as of 2019, the quality of voice transmission via Bluetooth is still poor, and it is not clear why Bluetooth SIG is not doing anything about it.' (The SIG is the trade organization that sets standards and runs certification problems.)
Not all Bluetooth audio in/out combinations drop in quality, though. So you may not have encountered this with a device you use. Or you may not know, as the sound you hear from others could be higher quality than the compressed sound they hear from your mic. You might need to record sound from your device or have someone record it on their end to see how good or bad it sounds.
Unfortunately, the only solution in most cases is to switch to a USB-based headset or USB mic and headphone combination. That ensures the best quality audio is used on your Mac. Some devices may have both Bluetooth and USB options, in which case you can use the USB connection when you need to get higher-quality audio input. That's what my kid did: the same mic input connected via Bluetooth captured the whole dynamic range of his trombone piece.
If you're having trouble with the quality when playing sound back, whether your Bluetooth device has a mic or not, you can try these tricks.
Jack & the secret door mac os. Select a different audio input device in the Sound preference pane's Input tab and in any software you may be using that lets you select audio input. This may prevent a poorer audio encoder from being used.
Check whether your device when connected is using a lower-quality encoder by pressing Option while selecting the Bluetooth menu in the system menu bar and viewing the menu for that device. This article at How-To Geek provides the extensive steps to use a developer app from Apple to force a higher-quality encoder.
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As ValdikSS notes, this duplex mode of sending and transmitting simultaneously is a problem. 'When this mode is used, both the voice from the microphone and the audio are transmitted to the headphones with the same quality…Unfortunately, as of 2019, the quality of voice transmission via Bluetooth is still poor, and it is not clear why Bluetooth SIG is not doing anything about it.' (The SIG is the trade organization that sets standards and runs certification problems.)
Not all Bluetooth audio in/out combinations drop in quality, though. So you may not have encountered this with a device you use. Or you may not know, as the sound you hear from others could be higher quality than the compressed sound they hear from your mic. You might need to record sound from your device or have someone record it on their end to see how good or bad it sounds.
Unfortunately, the only solution in most cases is to switch to a USB-based headset or USB mic and headphone combination. That ensures the best quality audio is used on your Mac. Some devices may have both Bluetooth and USB options, in which case you can use the USB connection when you need to get higher-quality audio input. That's what my kid did: the same mic input connected via Bluetooth captured the whole dynamic range of his trombone piece.
If you're having trouble with the quality when playing sound back, whether your Bluetooth device has a mic or not, you can try these tricks.
Jack & the secret door mac os. Select a different audio input device in the Sound preference pane's Input tab and in any software you may be using that lets you select audio input. This may prevent a poorer audio encoder from being used.
Check whether your device when connected is using a lower-quality encoder by pressing Option while selecting the Bluetooth menu in the system menu bar and viewing the menu for that device. This article at How-To Geek provides the extensive steps to use a developer app from Apple to force a higher-quality encoder.
Ask Mac 911
We've compiled a list of the questions we get asked most frequently along with answers and links to columns: read our super FAQ to see if your question is covered. If not, we're always looking for new problems to solve! Email yours to mac911@macworld.com including screen captures as appropriate, and whether you want your full name used. Not every question will be answered, we don't reply to email, and we cannot provide direct troubleshooting advice.
There are not many things I miss from Mac OS 9. But there's one that was really useful: the ability to test a hard drive surface. OS 9 disk formatter (I don't even recall it's name) had a 'Test Disk' option that would perform a surface scan of the selected hard drive. That was awsome to test for bad blocks on the drives.
Unfortunately, that's impossible to do with Mac OS X, at least with it's built-in software. There are some commerical applications to do that (like TechTool Pro), but I get a little pissed off when I have to spend a lot of money buying a software that does a zillion things when all I want is surface scans, and specially when I could do it with the 'old' OS and not with the new powerful UNIX-based one.
Bad Reception Mac Os Catalina
Well, Linux has the badblocks command that will do just that: test the disk surface for bad blocks. It's a simple UNIX command, so I thought there must be a port of that to OS X (and, of course, I could try to compile it in OS X as last resource). After some googling, I found out badblocks is part of the ext2fs tools. And, fortunately, Brian Bergstrand has already done the port to OS X, including a nice installer.
The installer installs all the ext2fs stuff, including an extension that will allow you to access ext2fs volumes on OS X. As always, this is a somewhat risky operation. Personally, I avoid as many extensions as I can, because they run too close to the kernel for me to feel confortable. So, if possible, install it on a secondary OS (like an utility/recover system on an exteral hard drive, or so).
The badblocks command will be installed in /usr/local/sbin/badblocks, and it will probably not be on your PATH, so you have to type the entire path when using, or edit your PATH environment variable.
Usage is simple. First, run the 'mount' command, so that you know the device names for the drives you want to test. You can obtain something like this:
arroz% mount
/dev/disk0s3 on / (local, journaled)
devfs on /dev (local)
fdesc on /dev (union)
on /.vol
automount -nsl [142] on /Network (automounted)
automount -fstab [168] on /automount/Servers (automounted)
automount -static [168] on /automount/static (automounted)
The internal hard drive is /dev/disk0 (note that /dev/disk0 is the entire drive, /dev/disk0s3 is a single partition). Imagining you want to test the internal hard drive you would type the command (as root):
badblocks -v /dev/disk0
Mac Os Download
This would start a read-only test on the entire volume. The -v is the typical verbose setting, so you may follow what's happening. This will take a long time, depending on the hard drive you use. For a 160 GB hard drive, it took between 2 and 3 hours in a G5 Dual 2 Ghz.
I mention this because time is an important factor when testing hard drives! You should run badblocks on a known-to-be-in-good-condition hard drive, so that you can get the feeling of how fast (or slow) badblocks is. Later, if you test a possibly failing hard drive, and badblocks progresses notably slower, it will probably mean that the hard drive is in bad condition (even if it doesn't have badblocks).
After running the command, you may get two results: your disk has, or hasn't badblocks! 🙂 You will see many outputs of a successful surface scan, so I leave here an example of a not-so-successful one:
/usr/local/sbin arroz$ sudo ./badblocks -v /dev/disk0
Password:
Checking blocks 0 to 156290904
Checking for bad blocks (read-only test): 120761344/156290904
120762872/156290904
120762874/156290904
done
Pass completed, 3 bad blocks found.
This is the result of a test on a 160 GB hard drive with 3 bad blocks.
Bad Reception Mac Os 11
After getting something like this, you may try to run badblocks again, in write mode. Note that this will destroy all the information you have on the hard drive! badblocks won't copy the information to memory, and than back to disk. It simple destroys it. The point of running a write-enabled badblocks check is forcing the hard drive to remap the damaged sectors. Hard drives have a reserved space to use when bad blocks are found. The bad blocks are remapped to that reserved space, until it fills. And this will only happen on a write. So, run badblocks in write mode, and then again in read-only mode. If badblocks finds no bad blocks, your hard drive is fine (for now). If badblocks still finds bad blocks, it means that there are so many damaged blocks on the disk surface that the reserved area is full. Forget it, and throw the disk away. It's useless.