Q: clipping sound on new iMac when Logix X is running

Kenny,

Bear in mind however, the Mech portion of the FD drive is only a 5400rpm HD.. and so it's performance if you use the Mech HD for audio samples/streaming etc..  will not be that great..... compared to an external 7200rpm FW or TBolt contected fast, non-green, HD

Test and see however... and fingers crossed!

it's actually only the 21,5" iMac that makes use of the 5400rpm drives. The 27" has 7200rpm drives, I am not sure if it is a 2,5" or 3,5" though, but by the sound of it I'd bet my money on it being a 3,5" drive.

The Apple websites even says in the tech specs that it's 5400 and 7200rpm respectively in the standard configuration, and looking at the disk in my system info it also says it has a rotational rate of 7200rpm.

In any case though, I am just a hobbyist and most likely never need the speed of a 7200rpm drive anyway when it comes to audio recording. For me it is more about the overall launch time of apps, and for that there is nothing like SSD (as a matter of fact I can barely use a machine that runs it system on a mechanical drive anymore. ).

So I am totally fine with handling two disks, as a matter of fact the one thing I dislike with the FD is that it determines what goes where, for example I might end up with several gigabytes of movies on the SSD, which I don't really want.

I was prepared to just let it do it's thing and leave it at that, but with these problems affecting audio as well, I'm thinking I might just be better off handling the data juggling myself. The only reason I got the FD option really was because I didn't want to pay for the SSD only option as it is still not enough to store all my photos, but I wanted to get rid of external drives at the same time. But the 3tb mechanical drive is good enough for me for quite some time, I am only up to about 500gb of photos so far anyway.

Huh!

I didn't know/realize that. I thought Apple had said (originally) they would only be using 5400 rpm Mech HDs as part of their Fusion Drive setups... though they use standalone 7200rpm Mech drives in the 27" 2013 non FD iMacs... but after doing some further reasearch you are correct without a doubt... 

Thanks for letting me know and bringing that to my attention.. Much appreciated!

no worries! to be honest, i have a vague memory of it being 5400rpm drives myself, so i was a bit surprised myself. i haven't put too much though into it, but i wonder if perhaps the first release of the fusion drives did in fact use 5400rpm drives in all configurations. either that, or i just dreamt it all up.

My iMac FD 27" came with a Seagate Barracuda 7200.14 ST3000DM001 3TB 7200 RPM 64MB Cache SATA 6.0Gb/s 3.5" mechanical drive plus the SSD of course.

Must the FD work in a single partition? Or is there an option where you can create 2 partitions where the 1st would be a FD and the second only on the mechanical disk? Then you would move all the loops to the 2nd partition and set it as storage for temp files too thus releasing the FD portion mainly for read purposes and starting up apps.

Maybe this would take some of the burden from the FD controller shuffling data to and from the ssd part. Just a thought...

The fix from apple (if any) would probably lowering priority of FD data moving. Should be an easy software fix without changing any hardware.

I also did some stress tests with an external USB 3 disk drive. If I leave those tests running long enough, eventually the disk is no longer recognized and the volume disappears. This is consistent with what happens with audio interfaces too.

If any of you has an external USB 3 disk, you could try and replicate this problem by running Blackmagic Disk Speed for several minutes and see if you get the same results.

poinggo,

I'm not sure you can partition the Fusion drive. I think this is why you cannot Bootcamp a Fusion Drive either.... which is where all the info on splitting a FD came from originally... though that might be more to do with booting up from either partition... Not sure. One of my clients asked me the same thing a few days ago and  and I cannot find any definative answer.. yet. It seems.. no.. but that could be wrong.

Apple tech support asked me to partition the fusion drive. It failed on the first go round.  The process froze and we had to terminate it (to my annoyance).

After erasing the whole FD and reinstalling the OS, with nothing else installed, they asked me to try again. We set the partition at about 250GB and started it up.  Again it froze at 75%.  Waiting an hour or so made no difference. 

The tech was surprised in that his reference said the FD could be partitioned.

I missed the 14 day window and the diagnostic showed nothing wrong with the hardware, but I'm tempted to push the issue harder with them.

TAOS,

According to this you can http://support.apple.com/kb/HT5639

At least for bootcamp.

After working closely with upper level Apple Care and the manager at my local Apple store, I was able to return my iMac 27 with FD drive today for a full refund, even though I've had it for a month. 

Just wanted to say hats off to Apple for doing the right thing.  They even through in the Apple Care for the replacement machine (same config but with a 3TB 7200 drive instead of 3TB FD) which I just ordered. Like for many of you, this was a frustrating experience but it's good to know that Apple values customer service.

I also wanted to say that I am using an Apogee Duet FW and it worked perfectly when booting from my backup FW drive.

- Ric

poinggo,

Ah.. they fixed this issue in an update....

http://support.apple.com/kb/TS4441

I also wanted to say that I am using an Apogee Duet FW and it worked perfectly when booting from my backup FW drive.

Yes, FW Duet should work fine.. USB Duet, not so much....

Glad to hear Apple took care of you....  as they should under the circumstances!

Hey All,

Just wanted to add myself to the discussion for statistical purposes.

27" Late 2013 iMac

3.5 GHz Intel Core i7

16 GB 1600 MHz DDR3

1TB FD

I believe I am experiencing issue #1 outlined by The Art Of Sound.

I experience the "rice crispie" effect in LPX shortly after launching the program. I initially thought it was related to the AI so I spent hours talking to Focusrite and Sweetwater about my Scarlett 18i20, but ended up just returning it. Borrowed an Audiobox by PreSonus from a friend earlier today and am experiencing the same issues. So, it sounds like my options are these:

1. Disable the FD and begin option 3.

2. Exchange my computer for one without a FD.

3. Wait for an update.

Does that about cover it? Also, I know this is a novice question, but I'm having a hard time finding a direct way to contact Apple Support. Any help? I'm located in the SE U.S. Thanks for everyone's input. I still have no solution, but there is comfort in not being out in the cold alone.

I just bought an Imac 27" i7 3.5 3TB fusion drive latest Mavericks. Same #1 issues with Apogee Duet, Apogee Quartet, Yamaha 01v96i AND THE KICKER...Blackmagic Intensity TB.  I'm a TV/Audio producer...I've been unable to record or edit audio and now I have to unplug all of the external hardware to get the audio to be stable enough in at least Premiere CC to export (though that's been troublesome too).  All interfaces work on my 2.66 Xeon tower and my late 2009 imac without a hitch running same OS and software. Took the computer back to apple store today, they want to keep it for a week...UGGG!  the tech seems to not take any of these forums too seriously even after i told him that Apple Care (after 2 hours on the phone with them) said there was no fix for the problem and to have the Apple store replace the drive with a 3TB SATA ($200 return to me) or 1TB SSD (additinal $500)...the local tech was a little bit of a know-it-all...aren't they all - but nice.  I've had it about 10 days.  Think I'll call them tonight and tell them to keep it.

jwweeks,

Yes it does sound like you have the issue as described... and your options are as you stated with the addition of...

You do have the further option of simply booting from an external drive (one that has OS X and LPX installed on it) which is simpler than splitting the FD drive... if you have a spare ext HD of course... and again wait for a fix from Apple.

To contact Apple...

http://www.apple.com/contact/

...and specifically for US Customers...  and Applecare

1-800-692-7753

Cheers..

the tech seems to not take any of these forums too seriously

Unfortunately that could well be the case as these forums are not populated by Apple personal for the most part.. but simply users like yourself and I... and there can be a lot of misinformation floating around.... so frankly I'm not surprised at that attitude. Not that I agree with it but I can see why that might be.

If only official Apple techs/Devs made their presense here felt, that would go a long way to providing more credibility to these forums...