The DiMarzio DP175S True Velvet™ is a vintage single coil pickup designed for the middle position. The True Velvet Neck and Middle models have the same specs except for reverse polarity on the middle pickup for hum cancellation in the 2 and 4 switch positions.
It's not difficult to make a vintage single-coil pickup that's clean and bright, but not so easy if you also want the high strings to sound sweet above the 12th fret. The DiMarzio DP175S True Velvet Middle pickup was designed to make this happen by tuning the coil to a frequency range that's bright but not thin. DiMarzio combined this with a magnet stagger specifically designed to enhance string balance, which produces great clarity, even with full chords.
The DP175S True Velvet™ is a further development of DiMarzio's Blue Velvet™ line. They re-tuned the basic frequency response to hone in on the strongest aspects of vintage single-coil tone. The best vintage single-coils emphasized a "sweet spot" where the sound is bright but not piercing. The True Velvet is tuned to this spot, making it equally effective for many playing styles, from the clarity of country music to the grit of Texas blues. The True Velvet Neck Model comes standard with hand-ground magnets and vintage cloth-covered wire.