Need computer audio advice.

All of my digital music is on my desktop iMac, a 500GB machine. I have only 70GB free space, so I think my drive is getting full. I was thinking of getting an external drive (say 1 or 2 TB) and simply moving all my music off the desktop and on to the external drive.
Is this a good solution ? Will there be any sonic problems ? Most of my music is CDs ripped and stored in lossless formats, FLAC or WAV. Some of my files are high res files 24/96 from HD Tracks. I stream over a network to a Logitech Squeezebox touch.
It this solution has problems, what would you recommend ?
Thanks, Matt
You have a few options.

Once you add an external hard disk, if you use iTunes, you can "uncheck" the box to keep your music library organised and prevent it from copying new songs you add into the folder you originally designated. This way, when you drag new files to iTunes to add them to the library, it will add the tracks into the library without actually copying the files over. And the files will remain in the external HDD.

Of course, you will still need an app like XLD to convert your FLAC files from HD Tracks to AIFF or ALAC.

While this method will work, I am a bit too OCD to use this. It means all your media files are all over the place and stored in a central place. This will also be important if you want to make back ups of your music library - and yous should since you know HDDs have a finite shelf life.

The method I'd propose involves getting a much larger HDD. It's cheap these days, so I am going to say 4TB. In iTunes, you have an option to specify where your music library is stored in Preferences/Advanced. Instead of user/Music folder, point it to the external HDD - say an iTunes folder in the external HDD. And in this case, you want to "check" the keep your library organised and copy files to the library.

You'll be asked if you want to move your existing library to the new location. Click Yes.

And iTunes will proceed to copy all your files across from your internal HDD to the external drive.


Remember I said storage is cheap? Maybe get two of those of external drives. And use Disk Utilty to duplicate your first external drive on the second. Do it periodically.

It's like insurance.

OK. We got the basics covered.

Now what else can you do to improve the playback quality on your iMac?

If you are handy with opening up the machine, I'd recommend getting an SSD and as much memory as your iMac can support.

Replacing a moving array of parts in a HDD with a solid state drive with no moving parts will help the computer work better as a music server, from what I've discovered. I suspect it's all the EMI and stray RF from all the magnets and moving parts.

Loading up the RAM allows you to benefit from the next stage - memory play - where tracks are loaded from the HDD completely first into memory and then played from memory.

To do this, you will need some software. The cheapest I think should be BitPerfect. It's available from the App Store.

BitPerfect does a couple of things in addition to memory play.
A. it allows INTeger mode and an exclusive use of the audio device.
b. it dynamically switches the sample rate to mix the source file you are playing. If you don't do that, Apple's OS will try to resample your music from its original rate (say 44.1kHz from your CD rips) to say 96kHz if that's what is set in Audio MIDI control.

You might think playing at 96kHz should sound better. But in reality, it depends on the algorithms used to upsample. And the Apple OS (as with most OSes) does a shitty job of this.

So keeping it "native" is better. If you do want to upsample, apps like BitPerfect will also do that for you. And it does a better job too.

Before you decide on BitPerfect (it's the cheapest but there's no trial option), you can also run trials of Pure Music (now in v2.0), Audirvana Plus (my recommendation based on price/performance as it does DSD as well) or Amarra.
Moving all your audio files to an external drive as you propose will work fine, and will not sound any different than what you are doing now. You may as well get a 3 TB or larger drive, as they can be found for around $100 or so.
Doggiehowser, thanks for your reply. It's a lot for me to digest, since I am not a computer geek. I will proceed carefully, first with a trip to the Apple store to check out external drives. I already have a 1TB drive used as back-up, using Time Machine. Maybe as an interim solution I could use the 1TB drive for music and purchase a 4TB drive as the new back-up ? Then I would have to set it up so it backs up both the iMacs internal drive and the external music drive ? Would this work as a first step? Thanks
I had used a MacBook for a bit and then a MacMini. In both cases I bought one of these to store my music and used the FireWire interface to connect to the computer. I mapped the music software (Audirvana, JRiver, Pure Music) to this external drive and you can do the same if you want to use iTunes. A simple and cheap solution.

I have moved on to a NAS set up but find the Oyen Digital HD is a nice backup storage solution. Two are affordable and a backup is worthwhile.
Firewire interface to an external disk is a better idea, particularly if you are planning to drive USB interface, either a USB converter or a DAC. You should minimize the other USB devices on the bus.

The computer should be dedicated to music playback and not your general purpose machine. I find the Oct 2009 Mac Mini to be a great choice because you can externally power it from a good linear power supply. Cannot do this on newer Minis unless they are modified. Laptops are not as good IME.

You can usually get a Oct 2009 Mini with Bluetooth keyboard, mouse and OS disk on ebay for around $375.00. Replace the HDD with SSD and upgrade to 8gigs memory. Put Amarra playback and XLD for ripping on it and you will have a world-class server. Also do the OS tweaks in iTunes iBooks "audio optimization guides"

Steve N.
Empirical Audio
Matt, when you use network you send data and not the music. The difference is that data has no timing - timing is recreated on the other side of network bridge. Your file format, amount of memory, type of HD, speed of computer, playback program etc. have no effect on the playback. It is remotely possible that mechanical HD will create more EMI than solid state drive but it is also possible that faster computer will do the same. I would just ignore it all. If you have choice on your Mac - get external Firewire drive (that's what I use on MacMini) - it is easier to daisy-chain them and they don't slow down main processor - minor and perhaps not important unless you use computer for other heavy tasks. External Firewire drive cost a little bit more (less common). Get two drives, as Doggiehowser suggested, and make backup. I have three drives and use "Carbon Copy". One drive is in use, one in storage and one at work. This protects me from theft/fire or computer/controller failure during backup (that could screw up both HD). I make new backup only to one drive at a time (alternate them) and only when I have more than 5-10 new CDs.
Good advice so 2 cents follows:

I have almost 30,000 AIFF tracks on a 2tb drive and will probably never need more storage. So, because you’re only using your Mac’s 500 GB hard drive for your OS and other file storage now, as little as 1 or 2tb’s may be sufficient for your needs. No need to buy a 3 or 4tb drive for less than a few 100 GB’s of music files. In a few years, hard drives may well be made obsolete by SSD's (Solid State Drives) or some other newer technology.

Simply because I’m more fluent with Windows than OSX, I use my Windows PC to rip and copy files using dBpoweramp software. However, I transfer those files via an internal hard drive to my audio room’s PC which is a Mac Mini. I also buy internal hard drives and external docking units for internal hard drives. These docks are plug and play and most are "hot swappable". In my audio room to connect to my Mac Mini, I use one from this company: As already mentioned, firewire is preferable, so I bought a dock with that capability. I also have a similar dock that I use for my Windows machine, only it doesn't have firewire capability, which makes it more reasonably priced (i.e. the more connections [USB, SATA, Firewire etc.] the higher the price of the dock. BTW, if you don't need a firewire connection, a USB or SATA dock can be used on both a Windows or Apple machine.

Internal and External Hard drives are hard drives. You don't need to buy one from the Apple store, or for that matter, one specified for use on an Apple. You can format the drive for use on either an Apple or Windows PC or both. is a site that I normally use for computer hardware, including hard drives.

As others have recommended, be sure and have a 2nd., or even a 3rd. (multiple) backup hard drives. You wouldn't want to lose all of the time you spent ripping your CD's and it's not a matter of if a HD will fail, it's just a question of when.

Moreover, always remember that not only should we protect our hard drive’s from mechanical/electronic failure with at least 1 back-up, but also from virus infections or power surges etc. Thus, multiple hard drives in one PC, or externally housed in a NAS or some other multi-bay storage unit, can all be simultaneously affected (damaged) by the aforementioned virus or power/lightning surge. Thus, I make sure to keep a hard drive that contains all of my music files offsite; in my case, at a relative’s house. One can't predict when a fire, flood, storm damage, lightning strike etc. can affect your home and its contents.

If you haven’t already found these sites, a wealth of PC Audio information can be found here: and The former site (Computer Audiophile) not only contains a forum, but the site owner, Chris, has published some very detailed and insightful instructions regarding ripping software, media playing software, etc. His site also contains his reviews of the hardware that is related to PC Audio.
I have been using 2Gb external USB drives with Squeezebox system via Wifi now for a few years. Works great, sounds great, a good way to go.

If there is an issue it will be with wifi bandwidth to handle high res files. I have thousands of CD quality lossless files I use, but have not tried Hires. The issue would be rebuffering delays if not enough network bandwidth for hi res, not sound quality. I have no problems with any of this with CD res files.
Thanks for all your responses. Very helpful.
You can get external hard drives from Other World Computing (OWC, or for a good price. I get most of my Mac aftermarket stuff there.

I run a Mac Mini modified by Mojo Audio. As part of the upgrade package, I moved from a 2TB OWC external hard drive to a 4TB AV drive. Same chassis, but the AV drive is much quieter and is more geared to serving up music 24x7, as the disk doesn't have to do head alignment and other maintenance that can interfere.

+1 on Steve's recommendation: Use Firewire to connect the drive if you're using USB for your outgoing signal.

Backup, backup, backup! After ripping and storing hundreds or thousands of CDs, would you ever want to do it all over again? Simply daisy-chain a second drive via Firewire, clone the disc (Carbon Copy Cloner), then store the second drive in a fire safe or off-site.

Lots of good recommendations here, but overall, know that you're not likely to find too many issues simply by moving your data to external drives.
Ignore most of the advice above, you're using a squeezebox. so it's simple. I use a 2TB HD and also the internal drive on an imac that's running LMS. No problem at all. Simply copy everything to the external HD, go into LMS and add that folder to the library and have it scan it.
The Squeezebox is convenient but IMHO it's not the best quality I've heard on my system. I think Steve sells a reclocker that can work with the Squeezebox that will improve things significantly tho.
Doggiehowser, My Benchmark DAC1 does reclocking internally and have pretty good jitter suppression (very clean sound), but according to Steve external reclocker does even better job. I have to try one someday.

I owned the DAC1 Pre before. It's not as free of jitter as the literature says.

I had a Marantz CDP, a Squeezebox Duet and a Wadia iTransport hooked up to it and even with bit perfect copies on all 3, there was a difference.
Doggiehowser, I wonder if other reclockers are sensitive to sources too. DAC1 isn't by any means perfect (as I thought before) since DAC2 promises improved suppression. Perhaps I'll try to add reclocker. Output signal should look like standard S/Pdif stream hence reclocking it again in DAC1 will further improve jitter reduction. I know that many people prefer NOS DACs but I really like clarity of DAC1 and it has good synergy in my system.