ATTENTION Current Mac mini/A+ users: Boot Mavericks from an SD card, load a RAMdisk, dismount your internal SATA drives, and pour a drink for the musicians walking out of your speakers!

[levandier]

 

This would seem the only logical explanation, but I just did a test: I timed the grey bar filling first for a track in a long playlist, and then deleted all other tracks in the playlist and reloaded and timed the same track. Both times it took 16 seconds for the grey bar to fill. So now I am confused."

 

Anyone?

 

Damien mentioned when Audirvana was first released that it preloads the currently playing track and the next track in the queue (so only 2 tracks will be stored in memory at any given time). The grey bar only shows the progress for the currently playing track - there's no visual feedback on the progress of the next track in the queue. You can confirm this by playing a short redbook file followed by a long DSD file; you'll see A+ continues to use a lot of CPU long after the redbook file has been preloaded.

 

Maybe we should request that Damien change how A+ works so that it preloads all tracks in the queue when playback starts (memory permitting). This would allow all processor intensive preloading to take place at once and it would also allow our hard drives to spin down as they wouldn't need to serve up the next song every 5 minutes or so.

[levandier]

BTW, to put the amount of memory needed for preloading into perspective, a 300MB album in redbook FLAC once decompressed to WAV and upsampled to 88.2kHz needs about 2GB of RAM, or about 8GB at 352.8kHz! :-o

[levandier]

While you are inside the Mini, install a SSD. Get a fast one 500MB/sec R/W and low power draw. Some are 2w active and others are around 0.1 watt active.

The SD card may still be better sounding. But a fast, low power draw SSD should narrow the gap in performance.

 

I agree that an internal SSD brings a nice improvement in sound compared to a spinning HD, not only due to the lower power draw of an SSD but also IMO because of its lack of moving parts. I read Barry Diament's post about the effect of mechanical vibrations on system performance and I have to say I agree 100% that vibrations have a detrimental effect. And computers are a big source of vibrational pollution with their spinning hard drives and fans. I've tried lots of vibration control methods and while most haven't improved the sound of my system, they all have a sonic impact, contributing their own sonic signature. I wasn't expecting this to be the case, especially with solid state gear which isn't microphonic like tubes but I've now had a drink of the Kool-Aid. :-) BTW, mass loading, as Barry says, is just a means of vibration control - extra mass lowers the resonant frequency and also acts as a vibration reservoir, releasing the vibration back over time; it doesn't make the sound more accurate but for many the change in sound is pleasing.

 

BTW, vibration control is another one of the reasons I use ethernet for file access rather than a direct connection via USB or FW - I don't want my computer directly attached to a vibrating, spinning hard drive.

 

My $.02 and sorry for the tangent.