Al Griffin

Q The head unit on my new Lexus has a USB input. This feature inspired me to purchase a 32GB flash drive and rip my CD collection using Windows Media Player. I used the WMA setting with the bitrate maxed out to 192Kbps for the first few discs I ripped, and those files played back in the car without issue. For the next batch I tried both the WMA Lossless and WAV formats. Although the files played back in Windows Media Player on my PC, they wouldn't play when I plugged the drive into the head unit’s USB port. Can you explain why? —Buck CornHauler

Q I recently purchased a pair of Definitive Technology BP 8060 ST tower speakers with built-in subs. They are connected to my Sony STR-DH750 receiver. What would be the correct speaker setting if I used the 8060s as my front speakers (set to Large) and continued to use my Sony sub for LFE instead of the ones built into the Def Tech towers? The rest of my system consists of two Infinity rear surrounds and a center speaker, plus two Bose speakers mounted on the front wall that I use for height speakers. —Kevin Bolin / Houston, TX

Q I read lots about digital to analog audio converters (DACs), mostly because of high-res computer audio. Here’s my question: Why do some DACs have a digital output? If the purpose of a DAC is to convert a digital audio signal to analog, why would you want it to output the signal in digital format as well? —Jacques Simard

Q I have a Denon receiver. Since the receiver has no phono input, I purchased a Pfantone AMP2 phono preamp so I could play records through it. The preamp works, but the volume level is low, even with the Denon’s volume turned all the way up. A friend suggested that the preamp simply doesn’t have the power to provide full stereo sound. Is this correct, or is there some other explanation? —Shaun Herron / via e-mail