Audio noise before and after muisc or video playback on MacBook - is this normal?

[cheez]

Hi all.

When I use my earphone on my brand new MacBook pro, it introdues noise similar to old cassette tape from the 70's. It sounds like crap. ^_^

This happens right before you play a music files or video files. And also happens right after the playback is completed. That noise really bothers me. It stops after about 5- 8 seconds and it's completely quiet. I also think, the noise is still there *while* playing the file, but I can't say for sure as I don't have any good way to test it.

I think I heard similar experience from another Mac user, don't remember who...

Is this normal????

Please assist.😳

 

[TheStu]

There is no additional noise that I can pick up on while the audio is playing, but yes, after you starting playing anything with audio (even a system beep will trigger it) there will be noise on the line after it ends. I am not entirely sure why it does it, but it is kind of annoying when it is late at night and you are using earbuds.

 

[cheez]

There is no additional noise that I can pick up on while the audio is playing, but yes, after you starting playing anything with audio (even a system beep will trigger it) there will be noise on the line after it ends. I am not entirely sure why it does it, but it is kind of annoying when it is late at night and you are using earbuds.

Yea it feels like crap. Cheez doesn't like it either. Good to know that I am not the only one experiencing this.

But surprisingly, and fortunately, once I tuned the equalizer for the audio (music) it sounds good. really good. :biggrin: It has more dynamic and wider range of sound qualities on this laptop than the old Sony laptop I had which was near top of the line. So that's good. 🙂

 

[forevermac]

I'm not experiencing this on my MBP (13-inch mid-09) with headphones (SteelSeries Siberia) over the Line out port. I've heard of this problem before here, but I've not experienced it under OS X. I've seen this on Linux on a MacBook, where there would be the "popping" described in the ASC thread (I managed to fix it in Alsamixer, but I'll save that for a different forum).

I'm guessing it's caused by the power running to the headphones, which probably is shut off after 8 seconds.

What headphones are you using?

Also, test you could run: find an extremely quiet MP3 (another thing you could do would be to take an MP3 and drop the decibels a ton, but that might be difficult), play it and see if you can hear the noise (and when). I don't know if this would work with a blank (silent) MP3, but I'd be inclined to say it wouldn't. If you can't find/get a suitable MP3, try looking for one beyond the range of human hearing (above 17k Hz should be fine).

 

[cheez]

I'm not experiencing this on my MBP (13-inch mid-09) with headphones (SteelSeries Siberia) over the Line out port. I've heard of this problem before here, but I've not experienced it under OS X. I've seen this on Linux on a MacBook, where there would be the "popping" described in the ASC thread (I managed to fix it in Alsamixer, but I'll save that for a different forum).

I'm guessing it's caused by the power running to the headphones, which probably is shut off after 8 seconds.

Very interesting point. Yeah it does feel like something could to do with the power. It's getting pretty annoying.

What headphones are you using?

I use Etymotic Research HF5. And I hear nothin on my iPod Touch, or the iPad 2 Ihad. No noise, zip.

Also, test you could run: find an extremely quiet MP3 (another thing you could do would be to take an MP3 and drop the decibels a ton, but that might be difficult), play it and see if you can hear the noise (and when). I don't know if this would work with a blank (silent) MP3, but I'd be inclined to say it wouldn't. If you can't find/get a suitable MP3, try looking for one beyond the range of human hearing (above 17k Hz should be fine).

I will try that when I get home. The noise comes on before playing the music and after. And also what TheStu has pointed out, such as system beep, or even something like opening a program or folder?😕 And then seconds later the noise stops with a pop.

OH and yes I did hear some noise while playing the music, the ones that are quiet. But I will continue to test just to make sure.

 

[vbuggy]

You are actually hearing it in the audio but at a much lower level. There's no magic with the soundchips fitted in Apple laptops - it's just your regular ol' laptop codec which has issues powering some headphones due to the indifferent engineering in the Apples - especially efficient earphones. There are notebooks that do a better job of it, and there are notebooks that do worse - the Apples are somewhere in the middle, not vested with some super-audiophile-grade codec just because Cirrus Logic makes the chip specifically for Apple.

We 'talked' about it here: http://forums.anandtech.com/showpost.php?p=32753117&postcount=83

Just get something like a Turtle Beach USB audio dongle (or hell, you can luck out most of the time with those <$10 fleabay specials), problem solved.

 

[TheStu]

You are actually hearing it in the audio but at a much lower level. There's no magic with the soundchips fitted in Apple laptops - it's just your regular ol' laptop codec which has issues powering some headphones due to the indifferent engineering in the Apples - especially efficient earphones. There are notebooks that do a better job of it, and there are notebooks that do worse - the Apples are somewhere in the middle, not vested with some super-audiophile-grade codec just because Cirrus Logic makes the chip specifically for Apple.

We 'talked' about it here: http://forums.anandtech.com/showpost.php?p=32753117&postcount=83

Just get something like a Turtle Beach USB audio dongle (or hell, you can luck out most of the time with those <$10 fleabay specials), problem solved.

I am so glad you got a chance to slam Apple, and promote your arguments all at the same time. I am happy that we could provide that opportunity to you.

How about, you just give an answer and then stop typing, let's try that on for size, eh sport?

 

[runawayprisoner]

Edit: silly double post

 

[runawayprisoner]

I'm not sure where the notion that some notebooks do better came from... In fact, it's sometimes worse if you get a notebook that doesn't output noise to cheap headphones.

It's a problem with the signal to noise ratio. Essentially, it's caused by an impedance mismatch. Happens when the source output has more impedance than the headphones can handle.

One way you can fix it is by using an attenuator, or... this thing:
http://www.earphonesolutions.com/leatwivoco.html?productid=leatwivoco&channelid=FROOG

Put your MBP at max volume output, then use the attenuator to reduce the volume until you can't hear the hiss or "ffffff" anymore, and you should be good to go.

Edit:
Also, just for reference, I've found that the MBP has an output impedance of around 24 Ohm, whereas the Etymotic Research HF5 has an input impedance of 16 Ohm.

Your iPhone and iPad work fine because last I checked, the output impedance of most iDevices are less than 10 Ohm... or practically any headphone should work fine.

The attenuator works because it takes high input impedance and then output again at low impedance, thus eliminating the noise.

A more elegant solution is to purchase new headphones that have higher input impedance. If you're interested, Apple's reference earbuds, the In-Ear ones, have an input impedance of about exactly 24 Ohm.

 

[cheez]

Wow, thanks for the input guys. Very good info.

Runawayprisoner, I leave my MBP system volume at around 35% not even one-half. Dang are you saying the noise will get worse at max volume? :ninja:

Thanks for the impedance and ohm info on these devices. It all makes sense now with all these noise.

🙂

 

[runawayprisoner]

Yeah, it'll get worse at max volume.

Reducing volume is a quick fix, but as I later edited it, the best way to do it is still for you to get an attenuator, or better headphones. Fixing volume on the MBP may or may not work depending on a number of factors.

Here's an article about it that probably explain it better than I do:

http://www.rothwellaudioproducts.co.uk/html/how_attenuators_work.html

I must admit that it has never been an issue for me, and it wasn't until your post that realized that it could be a problem, so the information I posted was just a portion of what I was able to dig up.

Here is where I originally found the information about the attenuator and the signal to noise problem:
http://forums.macrumors.com/showthread.php?t=451916

And then it's all Google work later on... I'm sure you can find more.

 

[vbuggy]

The problem with an attenuator is that although it'll reduce hiss, it'll also change the sound a tad. It's a solution, but since an attenuator will cost almost as much as the low-cost USB soundcards which will be a better solution - since it'll be an improvement on the underengineered crud on the Macbook.

Output impedance: runawayprisoner's oeuvre - misleading, incomplete info borne of no experience. All of my >30-ohm IEM's hiss - big-time - on the current MBP. In fact, a good percentage of my current *headphones* hiss - yes, even my exactly 24-ohm MDR-7520's.

Even a <$10 C-Media POS I got on ebay does better in this respect - and outputs better analog audio than the Macbook's codec. Something like the Turtle Beach Amigo (http://www.turtlebeach.com/products/sound-cards/audio-advantage-amigo-ii.aspx) will get you better results.

 

[runawayprisoner]

I'm not sure what your hate of the Macbook has to do with how to eliminate the noise going through the headphone port due to the difference in impedance.

If you doubt that, feel free to take it up to any engineer and they'll be able to explain it to you.

As far as your headphone experience go, ever thought that advertised impedance of a headphone is not actual? Take some measurements and you'll see that the actual impedance is always not what it's rated to be on headphones.

Please try plugging in something like ATH-M50 or Beyerdynamic DT770 Pro before making statements. If you still hear noise, it's a hardware defect, not a general blanket thing that happens to all Macbooks.

Even my ATH-FC700 doesn't produce that much noise, at max volume, on all of the Macs in the house.

 

[vbuggy]

I'm not sure what your hate of the Macbook has to do with how to eliminate the noise going through the headphone port due to the difference in impedance.

If you doubt that, feel free to take it up to any engineer and they'll be able to explain it to you.

As far as your headphone experience go, ever thought that advertised impedance of a headphone is not actual? Take some measurements and you'll see that the actual impedance is always not what it's rated to be on headphones.

"In fact, a good percentage of my current *headphones* hiss - yes, even my exactly 24-ohm MDR-7520's."

By exactly, I do also mean it tracks 24 ohms throughout the audible range.

Please try plugging in something like ATH-M50 or Beyerdynamic DT770 Pro before making statements. If you still hear noise, it's a hardware defect, not a general blanket thing that happens to all Macbooks.

Even my ATH-FC700 doesn't produce that much noise, at max volume, on all of the Macs in the house.

Hisses with the DT770 Premium.

Problem is, half-learned stuff you don't ultimately know anything about isn't any substitute for actually knowing that stuff, and real-life experience. Or for that matter, assuming that anything Apple has fairy dust on it.

MBP's have fairly mediocre audio in line with many budget general purpose notebooks, among other deficiencies. For best results, instead of working around it, replace the audio - especially as it's cheap to do.

 

[cheez]

Thanks for the inputs guys. I really appreciate it. And I do want to make note that runawayprisoner is extremely good contributor and does know a lot about Apple stuff. 🙂

Just to note, my 6 year old Sony laptop has none of these hiss / ffffff noise issue when using any ear phones I have used in the past. Yes, I tried the HF5 on it and did not hear any noise.

Maybe the MBP really does have issue causing these noises. I can tell you that I am not gonna replace my IEM just to get rid of the noise. HF-5 is damn good performing set (for stellar treble and dynamic sound). I might upgrade to the ER-4P later but not anytime soon.

I noticed the MacBooks don't have PCMCIA slot? Huh. I was thinking about getting me a nice SoundBlaster X-Fi card for it later. Don't know if going USB direction is good or what.

 

[vbuggy]

I'm sure he knows a lot about Apple. It's what he doesn't know but is aggressively unaware of, especially when it concerns the besmirching of his fairy dust-sprinkled treasures.

I'm sure it extends way beyond, but e.g. the sound chip on the MBP is a custom chip manufactured for Apple, but to him it's custom so it's better than anything else - he doesn't consider that since Cirrus supplies sound chips for pretty much everything Apple makes, the custom aspect is for cost or specific product packaging purposes. Apart from the fact that it has a different designation to what other PC vendors can buy, it's a fairly run-of-the-mill comprehensive codec in most respects. And it's analog performance as used out of the MBP is rather unimpressive.

USB is fine. Obviously if you want to get a higher-end soundcard that's your perogative but a $25 Turtle Beach (the one without the optical I believe works better for this task) will be sufficient to all but eliminate the issue. If you want something that pulls double duty as a standalone headphone amp as well, the Fiio E7 is a fairly bull****-free mobile DAC, and it won't break the bank. I can confirm it doesn't hiss egregiously with sensitive earphones.

Oh yeah, one other issue with attenuators - channel imbalance across the potentiometer range. Cheap ones will vary widely - i.e. left or right may cut out or be lopsided at certain volumes, etc.

 

[runawayprisoner]

"In fact, a good percentage of my current *headphones* hiss - yes, even my exactly 24-ohm MDR-7520's."

By exactly, I do also mean it tracks 24 ohms throughout the audible range.

Hisses with the DT770 Premium.

Problem is, half-learned stuff you don't ultimately know anything about isn't any substitute for actually knowing that stuff, and real-life experience. Or for that matter, assuming that anything Apple has fairy dust on it.

MBP's have fairly mediocre audio in line with many budget general purpose notebooks, among other deficiencies. For best results, instead of working around it, replace the audio - especially as it's cheap to do.

I'm fairly sure I put an article as backup for my statement. Where is yours?

If you don't have any backup for your arguments, then they are just generalized opinions. I don't think you have to resort to insult my knowledge here as I specifically stated that I just looked it up recently. If you knew more about it, please feel free to elaborate. Otherwise, I don't see how insulting my knowledge would solve anything. It's not even my knowledge that lead to that answer.

Also if you have any information about Apple's audio quality lacking behind, please, do provide proofs and evidences. Otherwise, I think I'm about done here, as I can't be bothered to respond to each and every one of your flame bait, dear sir. If you want a heated name-calling argument, please try elsewhere.

 

[vbuggy]

I'm fairly sure I put an article as backup for my statement. Where is yours?

Yes, but an article or posts irrelevant in the context of this discussion is a worthless article.

Buy a 7520. Measure it if you like across the frequency range - it will be 24 ohms. Listen to it on a current Macbook Pro. It's not hard 🙄

 

[runawayprisoner]

So if the article supports my argument, it must be wrong? Wow...

No, I think we are done here. If you want more argument, please look elsewhere. I'm not here to argue about anything. I'm merely here to provide a possible solution. If you think it's unsatisfactory, we'll leave it at that.