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Radiating

macrumors 65816
Original poster
Dec 29, 2011
1,018
7
FpXelVGPsBEwBwNT.medium


Simply put the Retina MacBook Pro 15" has a defectively coded speaker driver.

In Windows 7 you can see that it has 4 channels, left, right, center and sub.

Only the left and right work. The center and sub produce no sound.

The end result of this is that the tweeters (upper speakers in the photo) are the only speakers that produce sound, and the sound coming from the speakers is complete garbage. The sound quality is really bad (even with equalization), the volume is abysmal, and sounds below 1000hz are not reproduced.

This really sucks. Is there any way to possibly fix this and enable the mid-range speaker drivers in windows 7?
 
The same problem with Headphones..??

I do not use Windows or Boot Camp with mine, but I am curious (as a Pro Audio Engineer) does the Headphone Jack reproduce sound full range, or is it 'frequency limited' as well..?? Even the cheap Apple ear-buds will produce a 100Hz Tone easily..

Knowing that would at least tell you if it is a problem with the Amplifier/ Crossover Network for the Speakers, or if it is inherent to the Program/Software somehow.. or at least I think it should.. :confused:
 
I do not use Windows or Boot Camp with mine, but I am curious (as a Pro Audio Engineer) does the Headphone Jack reproduce sound full range, or is it 'frequency limited' as well..?? Even the cheap Apple ear-buds will produce a 100Hz Tone easily..

Knowing that would at least tell you if it is a problem with the Amplifier/ Crossover Network for the Speakers, or if it is inherent to the Program/Software somehow.. or at least I think it should.. :confused:

The jack reproduced the full audio range without issue. Windows 7 running on parallels desktop AND vmware fusion through the OS-X environment both also reproduces the full audio range without issue, so the culprit is in the windows 7 bootcamp driver.
 
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I think someone posted about this earlier. If you change it to quadraphonic it fixes it? Maybe, I can't quite remember.
 
I think someone posted about this earlier. If you change it to quadraphonic it fixes it? Maybe, I can't quite remember.

I've read that post, I haven't found anything that works though, and even when setting them to quadraphonic they don't seem to work.

Here are some frequency sweeps you can use to test the problem, I can't hear anything half way through the 16hz-1600hz test.

http://www.dr-lex.be/software/download/mp3sweeps-1f.zip
 
I found 3 other people that were having this issue so far. I'll start posting links to them.

https://discussions.apple.com/thread/4592255?start=0&tstart=0

Even if you enable quadraphonic and speaker fill it doesn't work properly, but it does make it better. In either situation sounds under 1khz can't be heard.

When sending audio signals to the front speakers alone they are brighter than the rear speakers, BUT both still have a crossover around 1khz.

Did Apple program the crossover for the mid range speakers backwards? It's hard to tell where the screw up is.
 
On my bootcamp setup for Win7 the speakers were already set to Quad, setting to stereo did show that the sound quality was reduced quite a bit. I hadnt really used onboard speakers as Ive done all my gaming at home when hooked up via TosLink to my Logitech Z-5500s.

Has this bug been submitted to Apple?
 
On my bootcamp setup for Win7 the speakers were already set to Quad, setting to stereo did show that the sound quality was reduced quite a bit. I hadnt really used onboard speakers as Ive done all my gaming at home when hooked up via TosLink to my Logitech Z-5500s.

Has this bug been submitted to Apple?

Whats the best way to submit the bug to Apple?
 
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