Which ones do you have? I've have never heard the Quantum 3's refered to as QLS 3's If you have the Quantum 3's you can get the driver spec's from the Infinity classic's web site: http://oellerer.net/infinity_classics/Quantum_3/Quantum_3_technical_sheet.pdf
Most of the drivers for the Quantum 3's are no longer in production but come up for auction from time to time. I believe the only driver you can still purchase is the watkins woofer.
Barry
Most of the drivers for the Quantum 3's are no longer in production but come up for auction from time to time. I believe the only driver you can still purchase is the watkins woofer.
Barry