Hello Gary,
Macs work just fine with Slimserver and the Squeezebox. I do not use a Mac. I have heard that MAX
http://sbooth.org/Max/ is a good program to use to rip to FLAC using a Mac
Itunes can be used with Apple Lossless, but there are some folks who do not care for it.
The BEST possible sounding mods I have heard is the SB2 with Sonicaps as main coupling cap and the Sonicap Gen 2 and Sonicap Platinum as bypass caps. The Gold Bybee Purifiers were also used in this mod. BlackGate caps were used liberally in the internal power supplies.
The power supply was the Ultimate MKII with Bybee Purifiers and Summit DC cable.
The cost for the SB2 mod is around $950.00
The Power Supply is $1150.00
The DC cable is $300.00
Total for all mods and power supply $2400.00 not including the SB2 and shipping.
The SB3 with Sonicap Platinums and Gold Bybees will come very close to the same sound. Because of the case size difference the full size Sonicaps cannot be used. The cost for the SB3 mod would be $900.00 or $2300.00 total, not including the SB3 and shipping.
The mods I do remove the analog audio op-amp. The analog audio is driven directly off of the DAC chip through the very high quality capacitors and Bybee Purifiers for the most simple signal path. The maximum output of the DAC chip is 1.1 VRMS.
I do not suggest using a preamp of any type. Quite a few amplifiers can be driven directly from the SB2 or 3. There is an internal volume control that will handle lowering volume just fine. If your amp and speaker combination does require more than 1.1 Vrms to reach full volume for your system, you can look at using a step up transformer, similar to what is used to raise the voltage of moving coil cartridges in a phono system.