[Tiresias]

Yes, on my otherwise perfect new machine I'm getting some buzz.

(T____T)

On certain tracks it is heard during high, trebly notes even when the volume is at less than half.

Is anyone else experiencing this?

It took me like 8 hours to migrate and I really hope I don't have to go back for a replacement.

[Tiresias]

I've been playing around a bit more and think that I have figured it out.

It appears to affect only early recordings—of which I have quite a few.

Early Billie Holiday buzzes.

A 1945 recording of Bach's Matthäuspassion buzzes like a mother ****ing bee hive during the high notes of every aria.

Lead Belly, Howlin Wolf and Louie Armstrong: Buzz, buzz, buzz.

It's as if my computer were horribly amplifying the noise and crackle on these tracks; or as if that noise and crackle were producing the buzz.

Perhaps the speaker clarity is the problem—rendering these old tracks unlistenable.

I don't know.

I've played around with the Equalizer Presets a bit but it doesn't help much.

Any suggestions?

[Tiresias]

Sorry to harp on but I have now established the crackle sound is also affecting recent classical recordings.

In short, it seems that along with the above all soprano and choral high notes are overtaxing the speakers and causing a noticeable and nasty crackly sound.

Never happened before.

Is it worth resetting SMC or is this just a shoddy speaker that will need replacing?

Or is there a different, smaller or thinner, speaker in the new unibody iMac that just can't handle this audio and therefore the only solution peripheral speakers ?

[Spheric Harlot]

Are you using any sort of audio "enhancement" plugin for iTunes?

Have you used any sort of script or tool to change iTunes song levels?

When you show the equalizer and set it to flat and move the volume slider at left to middle (0 dB), does it still distort?

[Tiresias]

Thank you Spheric.

No, I'm not using anything like that.

I don't even know what a script tool is and I use the presets for all my Equalizer levels.

I'm pretty sure now that it is not the speaker.

Portishead at full volume does not crackle, despite Beth Gibbons' alto-like vocals.

It's some sort of digital crackle that affects old recordings and classical recordings at high volume only.

In each case—because the recording is either old or made in a classical setting (i.e. not in a studio) there is a fair amount of ambient noise on the mp3 file itself. This seems to be the cause of the problem at high levels.

But it's okay. If I lower the treble (or the volume) a little on these tracks the problem is eliminated.

Also, I have some Dr. Dre Beats.

[Tiresias]

OMG!!!!!!! .

I just went through all the affected tracks and saw that thr volume adjustment was set at full.

I'd been too focused on Equilizer Presets to notice before.

This from a drunken night of listening to Bach arias and jazz at the loudest possible volume... I never readjusted.

Sorry for wasting your time.

( ^____________________^ ; )

I feel pretty stupid.

[Spheric Harlot]

Originally Posted by Tiresias 

This from a drunken night of listening to Bach arias and jazz at the loudest possible volume... I never readjusted.

Honestly, that sounds WELL worth the (slight) embarrassment of this thread.

Glad you figured out how to fix the issue.

[mattyb]

And more importantly, glad that the new iMac doesn't have a speaker issue.