Using a Balanced Source, such as Phono Source or a Computer
If you've been reading along and have absorbed the gist of our balanced headphone articles, you'll know that re-cabled, balanced headphones and fully balanced headphone amplification will get you killer bang-for-the-buck audio performance ---but you have to use a fully balanced source. There are two we really like.
Vinyl Sources
Sure, digital has gotten very good (and we'll get to that in a minute) but vinyl is organic and liquid-sounding, and just happens to be a very cost efficient way to get a balanced source -- not to mention it provides hours of platter picking pleasure at indie record stores, too. The coil in a phono-cartridge is naturally balanced, and if you run it to a balanced phono amplifier, voila, you've got a truly balanced source. (Tape heads make great naturally balanced sources, too---but if you thought vinyl was obscure try finding source material on 15-inch reels!)
Digital Sources
The proper way to get as close to perfectly balanced digital source as possible is to create the inverted channel by flipping while it's still in the numbers stage. Normally, DACs (Digital to Analog Converters) run with 0000… giving a low voltage to 1111… giving it's maximum voltage. In this case the output with digital audio is non-inverted (or improperly but commonly called, “in-phase”). But with a simple toggle of a pin, the DAC inverts its word sequence and runs from 0000… giving the maximum output to 1111… giving it lowest voltage, which inverts the audio signal---pretty much perfectly.
In our latest generation of HeadRoom balanced headphone amplifiers you'll find a number-crunching sweetheart of a balanced digital front-end for our fully-evolved balanced headphone amp circuits. We use two Cirrus Logic's flagship CS4398 stereo DACs, each running a channel and creating a normal and inverted audio signal, followed by discrete hand-matched circuit paths which allow our DAC boards deliver exquisitely matched pairs of balanced stereo signals to all four channels of our balanced amps. The result of this pure and very short path to your ears in HeadRoom balanced headphone systems is audio performance that can only be equaled by supremely hyper-expensive speaker-based systems.
We could end right here with you thinking about how your noggin can be transformed into a world-class listening room for a mere couple of thousand bucks, but there's something else. Our DAC boards have USB inputs, as well as digital TosLink optical and digital co-axial inputs. That means your laptop could be a perfect digital source for a high-end listening system; that means your Airport Express or Squeezebox is a perfectly good front-end anywhere in your home or office... That means most anywhere you are, you can be perfectly balanced, Right Between Your Ears.
>>Continue to Article IV- Going Balanced >>
