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andrewhollo
29th June 2008, 11:30 AM
I'm burning a whole stack of CDs today; converting to Apple Lossless. I'm noticing that the burn speed differs (anywhere from 4x to about 16x) and the resultant file's bit rates vary from about 500kbps to 1000kbps.

Also, I've set up iTunes to burn automatically when a CD is inserted, however, it doesn't recognise it first time; I have to eject and then re-insert. All works fine then.

I'm using an iMac 2.8Ghz. Any clues about this?

Andrew

jrad
29th June 2008, 11:48 AM
Hah, the post changed after I posted... Speed of burning varies depending on a few things... but I don't recommend burning at full speed. In the "cutting cost" way of things, many optical lenses have now been replaced with plastic ones, and when burning plastic can fog up (under heat) which causes the drive to pump more power though and thats where a lot of wear and tear occurs, I suggest you bring it back to 4x or 8x.

That said, when you select a speed that's the "maximum" burning speed for that session. It does change due to the circumference distance is smaller towards the middle of the disc.

As for Apple Lossless, it records data as it needs it, therefore it is variable. The "bit rate" output you see in iTunes is an average of the file's bitrate as it's always changing.

ClockWork
29th June 2008, 11:49 AM
In iTunes, click on menu item: iTunes and scroll down to: Preferences...
In iTunes Preferences, click the Advanced tab and inside the Advanced window, click on the third and last: Burning tab.

Next to: Preferred Speed - choose the speed you want it to burn at. Lower speeds provide better data integrity.

If burning Apple Lossless, select the: Data CD or DVD Radio button, and then click OK.

As to discs popping out when inserted, click on your Apple menu and scroll down to: System Preferences...

In the System Preferences pane, click once on: CDs & DVDs.

In the CDs and DVDs window, next to: When you insert a blank CD - click on the Ask what to do button and scroll up to: Open iTunes.

Quit System Preferences.

cw

andrewhollo
29th June 2008, 11:58 AM
In iTunes, click on menu item: iTunes and scroll down to: Preferences...
In iTunes Preferences, click the Advanced tab and inside the Advanced window, click on the third and last: Burning tab.

Next to: Preferred Speed - choose the speed you want it to burn at. Lower speeds provide better data integrity.

If burning Apple Lossless, select the: Data CD or DVD Radio button, and then click OK.

As to discs popping out when inserted, click on your Apple menu and scroll down to: System Preferences...
cw

Thanks for the advice guys. Two further questions:
a) what do you mean by data integrity? Do you mean that tracks will skip, or that sound quality will be poorer if I burn at faster rates?
b) Clockwork, it isn't that the disc is popping out. iTunes is already open and when I insert a disc, the computer (Finder included) fails to recognise it. It appears briefly in the iTunes menu (like, for a fraction of a second), then disappears. It ALWAYS shows up the second time I insert it.

Cheers, Andrew

rpjallan
29th June 2008, 12:18 PM
Are you burning CD's or ripping them into iTunes?

ClockWork
29th June 2008, 12:22 PM
a) Whatever is burnt to the disc will last longer if it's burnt at a slower speed. The slower the burning procedure, the more accurately it burns the information to the disc.

b) Even if it doesn't show up, when you click: Burn Disk in the playlist, does it burn all the same ?

Currawong
29th June 2008, 12:24 PM
First, make sure you have Error Correction switched on in the Importing preferences of iTunes, otherwise, iTunes will copy read errors into your files, which you don't want.

Apple Lossless is a method of music compression. Depending on the complexity of the music, the amount of compression will vary. That's why you get a very random range of bit rates.

Burning CDs is a very weird science. CDs themselves inherently have errors and have error correction systems built in to them, not to mention a considerable amount of clock data for the CD player to know how fast to spin to read the data correctly. Some years ago, it used to be all the rage to burn at the slowest speed possible, but then someone actually tested CD's burned at everything from about 1x to 24x on a 24x burner and found the slower speeds resulted in more errors! I don't know how accurate it is now, but for audio matters, people found that ripping and re-burning commercial CDs resulted in a better sound.

andrewhollo
29th June 2008, 12:26 PM
Are you burning CD's or ripping them into iTunes?

Doh. Yeah, I'm ripping them into iTunes. Got my terminology a bit confused. If I'm ripping, does speed make a difference, or should I still use 8x as a maximum?

ClockWork
29th June 2008, 12:45 PM
Doh. Yeah, I'm ripping them into iTunes. Got my terminology a bit confused. If I'm ripping, does speed make a difference, or should I still use 8x as a maximum?

Well - if you're not burning music to a CD-R, it doesn't matter which burn speed you set it to. Yeah - as Curra says above - iTunes -> Preferences -> Advanced -> Importing and click a tick into: Use error correction when reading Audio CDs.

Tick all check boxes in the Import window:



Play songs while importing (optional)
Automatically retrieve CD track names from the Internet
Create file names with track numbers (optional)
Use error correction when reading Audio CDs



and just at the top of that Importing window, next to: On CD Insert, click whatever it says there and scroll down to either: Import CD - or - Import CD and Eject -and then hit the OK button.

marc
29th June 2008, 01:00 PM
Ripping to Apple Lossless means the quality will be identical, as long as the CDs aren't scratched and can be read without errors.

As for burning speed... I've heard loads of people talk about different results at different burn speeds. I've heard mastering engineers say they'll only burn at 1x etc. I don't buy any of it. Modern burners with buffer underrun protection will alter their burn speed to stop errors and I think the difference in burn quality is mostly just voodoo science (the same people probably buy monster cables :p ).

Life's too short to burn at 4x etc. Just crank it all the way with confidence.

andrewhollo
29th June 2008, 01:23 PM
Ripping to Apple Lossless means the quality will be identical, as long as the CDs aren't scratched and can be read without errors.

As for burning speed... I've heard loads of people talk about different results at different burn speeds. I've heard mastering engineers say they'll only burn at 1x etc. I don't buy any of it. Modern burners with buffer underrun protection will alter their burn speed to stop errors and I think the difference in burn quality is mostly just voodoo science (the same people probably buy monster cables :p ).

Life's too short to burn at 4x etc. Just crank it all the way with confidence.

I've ripped about 20 CDs today and I've been listening to them with the volume nicely up - through valve amplification - and it sounds good. Not as good as my valve CD player, but ya gotta move with the times, huh?

Thanks for all the help everyone,

Andrew

marc
29th June 2008, 01:44 PM
I've ripped about 20 CDs today and I've been listening to them with the volume nicely up - through valve amplification - and it sounds good. Not as good as my valve CD player, but ya gotta move with the times, huh?
The only difference should be the digital to analogue conversion, assuming you're using an amp with an analogue input (fair assumption given that you said it's a valve amp).

So what you're really saying is "my CD player has better A>D converters than my Mac", which is quite likely. There's loads of good two channel USB, FireWire and PCI sound cards that will give you A>D conversion as good or better than high end CD players. I'm using a Metric Halo Mobile I/O audio interface and it sounds amazing! Definitely better than any CD player I've owned.

bullrout
29th June 2008, 02:24 PM
I'm burning a whole stack of CDs today; converting to Apple Lossless. I'm noticing that the burn speed differs (anywhere from 4x to about 16x) and the resultant file's bit rates vary from about 500kbps to 1000kbps.

Andrew

I think the speed difference is between ripping and encoding. The ripping part is slow and the encoding faster.

I have started using Max (http://Max) to rip and encode and it is worth a look if you want good rips.

rpjallan
29th June 2008, 02:34 PM
As for burning speed... I've heard loads of people talk about different results at different burn speeds. I've heard mastering engineers say they'll only burn at 1x etc. I don't buy any of it. Modern burners with buffer underrun protection will alter their burn speed to stop errors and I think the difference in burn quality is mostly just voodoo science (the same people probably buy monster cables :p ).

I reckon you're incorrect. Depending on your burner and your blank media, you can definitely have problems burning at too high a speed. I haven't really experienced any problems with audio but I have with video to DVD...

leon
29th June 2008, 03:15 PM
I'm burning a whole stack of CDs today; converting to Apple Lossless. I'm noticing that the burn speed differs (anywhere from 4x to about 16x) and the resultant file's bit rates vary from about 500kbps to 1000kbps.

Also, I've set up iTunes to burn automatically when a CD is inserted, however, it doesn't recognise it first time; I have to eject and then re-insert. All works fine then.

I'm using an iMac 2.8Ghz. Any clues about this?

Andrew

Andrew all of your importing issues are due to the fact that the 8800GS in your machine is actually a mobile chip (8800m), and Apple didn't tell you. Personally I would return your iMac as defective and get a Dell.

ClockWork
29th June 2008, 03:19 PM
And that is why... if I ummm give... something to someone I like a lot, I'll burn it @ x1 or x2 or x4, but if I don't give a toss about them, I'll burn it at x24 : the milk of kindness. Ha!

The explanation I was once given by Mr Choi of Try & Byte, was that at a higher burn speed, the burning laser did a kind of a light job of inscribing the data to the disc, and the con to this was that the if the media of certain CD-Rs is softer or more malleable, when a "playing" laser reads the data, it can be warm enough to obliterate the tracks as it reads them, so over time, a very fast burn being played over and over has a life expectancy of around 6 months.

At least, this is the what I was told, and I respect Try & Bytes knowledge.

cw

ClockWork
29th June 2008, 04:26 PM
Leon - I knew you were taking the piss, if that's any consolation.

This is the old - "pack your computer back into its box and send it back to whoever sold it to you, because etc etc" story, after said tech realises that customer's office has a total power black out, and can't fire up the the comp.

:)

marc
29th June 2008, 04:28 PM
I reckon you're incorrect. Depending on your burner and your blank media, you can definitely have problems burning at too high a speed. I haven't really experienced any problems with audio but I have with video to DVD...
Bad media is bad media. If a certain brand CD media can't handle higher speeds in certain brand drive, then that's a totally different story.

I'm just talking about the hokus pokus superstitious attitudes that somehow emerge with these things. Digital is digital. Sure, CDs can misread and have errors, and different things will affect the quality of the burn at a microscopic level. However, when digital equipment fails (CDs, DAT tapes, hard drives, SSD etc etc), it usually fails spectacularly.

Anyone who tells you they can hear the difference between a CD burnt at 4x and another at 24x is either lying to you or themself. It just doesn't work that way.

Bring on the flames by the "audiophiles"! ;)

leon
29th June 2008, 04:28 PM
Leon - I knew you were taking the piss, if that's any consolation. :)

At least someone did. My fault for not using a smiley face or whatever the kids are using these days for delivering tone.

andrewhollo
29th June 2008, 04:31 PM
The only difference should be the digital to analogue conversion, assuming you're using an amp with an analogue input (fair assumption given that you said it's a valve amp).

So what you're really saying is "my CD player has better A>D converters than my Mac", which is quite likely. There's loads of good two channel USB, FireWire and PCI sound cards that will give you A>D conversion as good or better than high end CD players. I'm using a Metric Halo Mobile I/O audio interface and it sounds amazing! Definitely better than any CD player I've owned.

Thanks Marc for this advice. I wasn't even aware that you could buy such cards. I'm a bit of a sound quality Nazi so I'll look into getting such good sound out of my iMac using something like you suggest.

I've got a 10+ year old Musical Fidelity Valve CD Player and I'd love to find something that sounds as good. The CD players I've auditioned in the past few years which, to my ear, sound any better, are all $4k+. The only thing wrong with mine is that the lid (supplied by Philips) is broken and won't close without a 3kg weight (like a book!) on top of it. Not exactly an user-friendly experience.

Andrew

marc
29th June 2008, 04:44 PM
Ok, sounds like you really do care about quality!

In terms of getting the absolute best out of your Mac... I'd audition the Benchmark converters. They're supposed to be truly amazing. I'll be looking into them one day when I'm wealthier!

The DAC1 - Benchmark Media Systems, Inc. (http://www.benchmarkmedia.com/dac1/)


Benchmark's Advanced USB Audio technology is truly 'Plug and Play'. When connecting to a USB port on a computer running Windows® 2000, XP, Vista, or Mac OSX, the computer will automatically and instantaneously recognize the presence of the Benchmark USB device. Any audio played from the computer will then be routed to the Benchmark USB device immediately. There is no software to install or configure.

They're actually not *that* expensive if you're already looking at $4k CD players. USD$1275 RRP for the USB model, which will be close to the best output you'll get from any DAC. I'm not sure how much you know about converters, but they're the most important part of the equation and a lot of the high end CD players share similar chips (as do high end music studio audio interfaces).

I wasn't expecting it at all, but I noticed a huge jump when upgrading from a MOTU audio interface to the Metric Halo Mobile I/O I have today.

Other brands worth looking into:
- Welcome to Metric Halo (http://www.mhlabs.com/metric_halo/)
- RME: Home (http://www.rme-audio.de/en_index.php)
- Apogee Electronics: Premium Digital Audio Solutions (http://www.apogeedigital.com/)
- DA-2 Home Page (http://www.prismsound.com/music_recording/products_subs/da2/da2_home.php)

An added bonus is that all of these converters are 24bit and at least 96khz, meaning you're future proof. Finding 24bit/96khz music to buy isn't though (most is 16bit/44.1khz... CD or 16bit/44.1khz compressed... iTunes etc).

Avoid anything cards that sit inside your computer, as there's a lot of electrical noise that tends to result in noisy output.

andrewhollo
29th June 2008, 05:01 PM
Thanks Marc for opening my eyes (and ears) to this stuff.

At first glance, the Apogee appears to be the most Mac friendly; also the Benchmark gear claims to plug'n'play. I don't want to muck around with lots of settings and having to tweak the gear (also, to be honest, don't want something sitting in my living room that looks like it belongs in the broadcast or recording studio!)

I wasn't actually wanting to spend $4k (!) . . . that's simply the entry price for something that I can hear a discernible improvement on my existing MF Player. Do you know anywhere in MEL which has this sort of gear setup with Macs for listening?

Once again, most appreciated,

Andrew

Currawong
29th June 2008, 05:19 PM
I'm using a ZERO DAC/headphone amp at the moment, upgraded. The overall cost would be somewhere around $300 but the sound is fantastic, miles ahead of what the Mac puts out by itself, especially with a high quality glass optical cable. Of course the Benchmark Dac 1 would be better still...

andrewhollo
29th June 2008, 06:12 PM
I'm using a ZERO DAC/headphone amp at the moment, upgraded. The overall cost would be somewhere around $300 but the sound is fantastic, miles ahead of what the Mac puts out by itself, especially with a high quality glass optical cable. Of course the Benchmark Dac 1 would be better still...

This also sounds interesting, especially given this review (http://www.head-fi.org/forums/f5/review-zero-24-bit-192khz-dac-headphone-amp-pre-amp-269458/). Do you use this with phones, or as a pre-amp? It looks like you can get one Ebayed over for under $200; is that how you bought yours?

Andrew