BAASnotes.com – Bay Area Audiophile Society

Tips for Better Mac CD Rips

I’m using a used 15″ Intel-based Macbook from late 2006. I know other models would give me the best sound from a Mac, but I can’t afford them.

You should get excellent sonics from the MacBook. It should not be the weakest link in the digital chain.

Do you use an external drive and software other than iTunes to rip CDs to your Mac computer(s)? Some folks use a Plextor PX-Premium CD-RW drive and AccurateRip XLD software (or something like that). They say the sound is much better.

I use the standard Mac internal drive (which is quite good). I also own a Plextor, but cannot hear a difference when using it (one exception below).Using my library (~1600 disks) for the samples, my own (informal) testing yielded the following results for Mac ripping software:

• iTunes
  • By far the easiest and fastest, but 2-3% of disks have an audible error (which I find unacceptable)
• Max
  • Rip takes 1.5x longer than iTunes, but error rate far less than 1% (acceptable to me)
  • Fairly easy to set up
• XLD
  • Rip takes ~3x longer than iTunes, but no errors encountered
  • Somewhat difficult to set up, and some manual reconfiguration necessary for every disk
  • I find both the rip times and difficulties unacceptable for normal use – I only use this for “problem disks”

A note about the ‘audible errors’: In my experience, these only occur in the first several seconds of “Track 1.” They are most commonly momentary dropouts. This behavior suggests to me that they are caused predominantly by “disk offset” issues. XLD explicitly allows the (power) user to compensate for the offset. It has other cool error-avoidance features as well. But it’s hard to live with….

Do you use a special USB cable? From whom?

I run Firewire, which I generally recommend for Mac users. I have never heard a USB or Firewire cable make a difference. But some in-the-know folks claim that they do. (If so, this would be another ‘audiophile mystery’ to scientists.)

Is it FLAC files that won’t play with iTunes on a Mac.

Correct. (iTunes can be made to play FLAC, but it’s not worth the effort!)

What converter do you use? I tried hunting for one, but couldn’t get it to work.

Max does a great job (as does XLD). I recommend using MP4/Apple Lossless format. I have never heard a difference between lossless compression and no compression.But a Mac using Firewire is a far more robust machine than PC/USB. To give you an indication, I often receive email, browse the web, download a file, and backup a hard drive simultaneously – while listening to flawless 24/192 (losslessly compressed). The only way that I’ve been able to adversely affect playback is to play (at 1x) the same CD that I am ripping (at 4x)!

Does Bandwidth Beyond 20khz Improve Sound Quality?

Some folks over at the SlimDevices Forum (here) are currently debating the impact of this 2000 psycho-acoustic scholarly research from Japan.

The results of the study support some remarkable and far-reaching conclusions:

• Frequency content beyond 20khz enhances human perception of music – test subjects favor it over lower-bandwidth material.
• Brain activity can be measured and used to correlate subjective assessments of the subjects.
• The form of ABX testing most commonly used in listening tests – several seconds of sound separated by less than a second of silence while switching samples – is inappropriate to measure a human’s assessment of musical content. The brain takes longer to form aesthetic judgments.

These tests were conducted in a controlled setting using double-blind protocols, direct measurement of brain activity, and  a statistically relevant sample size. Pretty solid.

These conclusions could have far-ranging implications to audiophiles:

•  A high-bandwidth system is necessary to full enjoyment of music.
  • Ever hear of a super-tweeter?
• Properly done, “high resolution” formats (e.g., SACD, HrX) enhance listening enjoyment.
  • More material please! And affordable high-resolution DAC’s….
• The rapid-fire “test tone” method of audio ABX testing is inappropriate to measuring human satisfaction of reproduced music.
  • Ban their use in audiophile settings and discussions.

Wow. Weighty stuff to consider this weekend.”Hypersonic” indeed.

In a future piece, I’ll discuss some of the factors that both the paper and the often-didactic forum discussion miss….

On Bandwidth (and Sampling Rate)

For our technically-minded members, I’m sure that you’re aware of Fourier Analysis and the Fast Fourier Transform (FFT) that revolutionized signal processing. For others, the core idea is that any signal can be efficiently decomposed into a number of sine waves. The more sine waves, the better the approximation.

The graphic at left shows a number of such approximations to a square wave. Engineers (even audio engineers) love square waves because of their infinitely rich harmonic structure. Listen to this sound clip (sin-sq-440-128k.mp3) to hear the A above middle C (440 hz) – first as a pure tone for 10 seconds, then 10 seconds as a square wave.

Sounds a bit like clipping, doesn’t it? It should – as the illustration below clearly shows.

Getting back to the first graphic (above left), we clearly need a lot of sine waves to approximate harmonically rich sound signatures like a square wave (or a bowed string). And those sine waves must be of increasing frequency. Thus, we need a lot of (analog) bandwidth. If we’re in the digital domain, this translates to a fast sampling frequency.

Hopefully this analysis helps to illustrate why many audiophiles desire 96+ khz  sampling (e.g., SACD) and/or ultrasonic analog system bandwidths (e.g., ribbon tweeters or supertweeters).

But the jury’s still out on whether these characteristics are needed to render a truly accurate musical event.