Hardware Accessories

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Hardware Accessories

NAS Storage

iXsystems FreeNAS mini: a ZFS-based turn-key NAS


In addition to being a computational device, Apple Computers are quite useful for audio and video applications. Some third-party hardware to enhance the user experience is definitely worthwhile. The following is not meant to be in any way exhaustive, but hopefully hints at some possibilities.


Many Apple computers have an optical audio out port, and all have USB ports. My mac mini has an optical output port that is the same as the 3.5" mini headphone jack. (It also has an optical input/microphone jack). If you plug an ordinary set of headphones in the audio output, or an adaptor to connect to RCA cables, etc, you can get a reasonable-sounding analogue audio output that is produced by your computer's internal hardware. However, using an optical cable (or a USB cable) will permit you to bypass your computer's internal Digital to Analogue Converter (DAC) in favor of an external one of higher fidelity, should you so choose. This enables you to use your computer as a high-fidelity music server for a stereo or home entertainment system. I have a mac Mini for just this (and movies).

USB Connection and USB Speakers

So-called USB speakers allow you to bypass the DAC in the computer for one that is external (and presumably better). From what I can tell, Bowers and Wilkins makes the best speakers for the iPod (the Zeppelin and mini Zeppelin, the latter of which we have, and you can plug directly into your computer using the USB digital connection). It sounds great, but isn't optimal for a dedicated, full-time sound-system connected to your computer (unless you like sound off to one side, hidden behind the monitor, or sitting in front of the monitor). Separate computer speakers in such a situation would clearly be an advantage.

I am waiting for these USB (digital) speakers to come out in a few weeks:

TX583_AV1.jpeg TX583_AV5.jpeg

The preliminary reviews on the Apple site suggest they are even better than the Zeppelin.

Optical Cable

The optical audio output of my Mac Mini requires a "Mini toslink to toslink" optical cable. You can pay lots of money for this, but all optical signals either work, or they don't. This one costs $0.31 via Amazon.com


External Digital Analogue Converter

One can spend thousands of dollars on a DAC for a stereo or home entertainment system. I found a particularly nice one that for me was expensive enough (even after saving on that optical cable). I just acquired this beauty, the Peachtree Nova (which, fortunately, is put together better than the Chevy Nova). In addition to a truly outstanding DAC, it has a tube pre-amp that helps bring what Neil Young called the "anonymous wall of digital sound", even compressed mp3 files, to life:


They also make a similar one with an iPod doc that allows you to use the external DAC in the Peachtree unit instead of the iPod's own, more limited one. It is called the iDecco. I was very tempted to get this, but I needed the extra power (80 W vs. 40 W.) to drive my speakers (B&W CM7). For an office or smaller room, the iDecco would be ideal.


Once you decide you cannot live without one of these, you will be obligated to get some decent speakers and/or headphones (both units are also headphone amps).

Reviews are here and here

Connecting the Interface

The optical (or USB) connection is pretty much "plug and play." If there is static, or no sound, there are two places one can make adjustments. The first is the "Sound" pane in System Preferences. Click on the "Output" tab and you should see something that looks like this. If it doesn't, make it so:


You can make further adjustments to the sampling rate and so forth using /Applications/Utilities/Audio Midi.app. Open the "Audio Devices" window and you should see an interface that looks similar to the following:


You can change the format (the maximum output frequency can only be 1/2 of the sampling frequency) and the bit-depth (all my Apple lossless files made from CD seem to be only 16 bit, so 24 bit might be overkill, but it doesn't hurt anything). Since I also have some 24-bit lossless files, I just leave it at that.

One peculiarity (bug?) of iTunes is that it reads the selected output set in Audio Midi when it opens, and sticks with those settings (word-size and sampling frequency), so if you change one of these after the fact, iTunes won't respond the way you intend. Shutting it down and restarting resets to the newly selected sampling frequency; leaving the bit-depth at 24 is probably the simplest option for that parameter.


A nice, free, light-weight, Cocoa-based music player application called Play.app that is cleanly integrated with CoreAudio has the ability to read the sampling frequency from the music file it is about to play, and then automatically changes the Audio Midi setting to correspond to it. This presumably avoids possible degradation due to resampling. (I am unconvinced that any such degradation is even audible, but I guess it doesn't hurt to be cautious.) You need to download the "unstable" pre-release version of Play to get this feature.



The same Mac Mini I use as a music server also is hooked up to our TV to watch movies and other such content, play games for the kids, and so on. (Apple TV, though less expensive than a mac Mini, is much more limited, although ATV2 permits streaming, so is actually a great alternative). The best way to do this, like audio, is with a digital rather than analogue connection. With the 2010 mini, there is now an HDMI out, and this can go directly to your TV (or indirectly via a HT receiver if you have that). On older Mac minis (and other macs), you can attach an HDMI to DVI cable to the mini-DVI to DVI dongle. A slightly better way would be to use a single cable with mini-DVI at one end and HDMI on the other. The HDMI can go directly to the TV or wherever suits you, and the TV can double as a computer monitor. For iTunes and Front Row, the 1080p resolution setting should be fine. I found even with a 52" screen that I need to decrease the resolution in order to see the screen for more involved computer activities. Ultimately, using a VNC remote display may be more handy.

If you have an iPad, iPod touch or iPhone, the "Remote.app" free application provides a very convenient interface with iTunes (which must be open and the front-most window). Set the TV/movie viewing preference to always open in full-screen to minimize the need for manual intervention.

Unlike the 2010 mini, on some systems, audio doesn't get channeled through the DVI/HDMI connection, so you must provide this separately as an input to your TV, home theatre system, etc, either in analogue or digital form, the later via optical out.

LCD Stereo: Zalman monitor

The least expensive and perhaps best option for stereographic display is the new Zalman LCD monitor.


Please refer to the COOT wiki page that describes how to set everything up for coot, and to the PyMOL Zalman page for a useful general description.

With the proliferation of LCD 3D TVs, this sort of think will probably become commonplace.

Controls and Input Devices


My favorite wireless keyboards:

For the Mac Mini audio/video server, so you don't need to have a separate mouse:


For a desktop with a separate mouse:



The "magic mouse" is a major improvement over previous versions.

Get this:


Program it with "Better Touchtool" to recover functionality like Button #3

Avoid this as it is an ergonomic disaster and the little ball goos up with secretory filth:



PowerMate Dial


Griffin Technologies makes a metal dial that is programmable and can be used with O, PyMOL and Coot, among other applications.

PowerMate Dial web site

Here are instructions on how to configure it:

PowerMate_dial_configuration_v2.x for O. Most is generalizable, so read this first even if you read the following:

Using powermate dials with PyMOL

Using powermate dials with coot

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