Mac IT Help: July 2014

7/30/14

My $752.64 cup of coffee

The current record for the most expensive cup of Starbucks coffee is $55 for a "Sexagintuple Vanilla Bean Mocha Frappuccino." If you aren't into Starbucks coffee you could pay $635 per pound for a bag of Kop Luwak coffee. The beans are collected from the feces of Civets after they are force fed coffee berries (Yuck!). But both of those pale in comparison to my $752.64 cup of coffee. And I didn't even get to drink it.

Like many of you coffee fiends out there I'm sure you love a nice hot cup of coffee while you check your morning email or browse the web. I do too. But if you aren't careful, a moments inattention can cause you to spill it. That's what I did. Not a big deal really. It's just a cup of coffee. But when any liquid is near your lap, especially hot liquid, you tend to jump back a bit. I did that too until I noticed that the brown flood of coffee was spreading and it was heading directly toward my new MacPro even though the Mac was a good 2 feet from the site of the spill.

Did you know that some of the most touted features of the of the Late 2013 MacPro are it's thermal core, quiet operation and new fan design? A single fan sits at the top of the Mac and draws air up from the base to cool the thermal core thus drawing the heat up and away from the electronics. As I watched the tsunami of coffee head toward my Mac I found out just how powerful that quiet fan was.

Like an over powered Suck-O-Lux vacuum the Mac pulled in the coffee where it disappeared inside. I lunged forward to yank out the power cord but before I could get to it I heard a pop, my screen went dark and my heart hit my stomach. A trip to the Apple Store for repairs and over $750 later I had my Mac back. I vowed that this would NOT happen to me again.

During the week and half repair I thought about the accident and what I wanted to do to prevent any recurrences. The new MacPro is gorgeous machine. It should be on display. It's small, fits perfectly on your desk and I really wanted to keep it there. After thinking about it I decided that what I really needed to do was to get the Mac up off the table and away from any future spills. So, like many dedicated Mac fanboys, I decided to put my Mac on a pedestal, literally.

A couple of sketches later and knew I was on to something. I wish I had the skill and tools to make my pedestal out of anodized aluminum but I'm an amateur woodworker so I made it out of wood. I worked through several iterations of drawings to get it just right and even added a built-in slot for a USB 3.0 hub. I added a nice ebony finish it to match the black of the MacPro and I was done.

Here's the finished product

It's hard to tell in the photo but the Mac sits in a circular depression that I routed out on the top of the pedestal. Being an aerodynamicist by degree I knew that the airflow was critical so I made sure to round over the lip of the depression so as not to impede the airflow.

All in all I think it looks good, works well and will hopefully protect me from any future spills. If I were to do it over again there are a few improvements I would make in the design and manufacture but for now I'm happy.

7/19/14

What is a DAC and do you need one?

When I got my new MacPro I knew it would be faster, quieter, smaller and cooler than my previous hulking MacPro from 2009. I love my new machine but like every honeymoon, once the newness wears off you realize it's not perfect. Don't get me wrong, I am still head over heels in love with my new machine it's just that the audio performance was adequate at best. I'm not talking about the tiny internal speaker. I knew that would be horrible for any sort of music. I'm talking about the listening to music on nice external speakers. Why didn't it sound better than my old machine? Doing some research I found out that your audio performance comes down to the internal Digital to Analog Conversion, better known as DAC.

Every Computer, MP3 player, iPod, iPhone and music device out there has a small chip inside that takes a digital file and converts it to analog audio. Depending on the DAC design, the chip will smooth out the rough spots, fill in the digital holes and balance the volume. Just like computers CPU, the better designed the DAC chip is, the better the sound quality. There is a huge difference in abilities & quality between a DAC in a $5.99 CD player from Walmart and the DAC in a $1000 sound system from a high end audio store.

In a perfect world your music looks like this and sounds great

image source

Here's a representation of the output from a normal DAC

image source

Notice how it approximates the curve with a stair-step function? That's not the best sound and to a discerning ear it can sound awful.

I won't bother you with all the technical details of what makes a good DAC, just know that there is a balance of bit rate, sample rate, filters, clock-rate as well as production costs.

Some audiophiles say only an old fashioned tube will give you the "warmth" of live audio. Some argue that upsampled bit-rate is the key. There are a ton of articles and arguments out there on what makes a good DAC and if it's worth the cost. I'll list some links at the bottom of the post if you are interested. For now, just know that as expensive as the new MacPro is, one item that isn't top tier is the built in DAC.

I did some digging and found out the MacPro probably uses a chip based on the Cirrus Logic CS4207. Not a bad chip but there are better.

So after all this technical talk be aware that there are a lot of DAC choices out there. DACs are built by every major electronics firm and a lot of independents as well. Look around, you'll find them. After months of looking I finally decided on a quality DAC built by Schiit Audio. Yeah, go ahead and say that name out loud and laugh, they laugh at their name as well.

"Yes, that is our name. Shih-tah. It's a proud German name, host to a long line of audio engineers who slaved away in crumbling Teutonic fortresses as lightning lashed the dark lands outside, working to perfect the best amplification devices in the world...

Or, well, no. Yep, Schiit is our name, and it's pronounced, well, like "hey man, that's some really good Schiit!" And now that we have your attention..."

With my DAC I also purchased a pre-amp volume control and have never been happier. Here's a diagram of my audio setup:

The sound quality with the DAC & speakers is wonderful. Much better than the analog output directly from the Mac itself. If you are an audiophile or just someone interested in getting better sound out of your Mac, I highly recommend looking into a DAC.

Links: