I'm no expert, but have archived a number of interesting links for the Infinity QLS1 that may be of some use if you get the chance to own a pair.
If you come accross other links please add them! :thmbsp:
The Quantum Line Source was Infinity's largest speaker of 1976, a 4-way 17 driver tower consisting of 8 front firing EMITs (Electro Magnetic Induction Tweeter) + 1 rear firing EMIT, 6 soft dome midrange drivers, 1 mid-bass coupler driver in a tube TL alignment and 1 Watkins 12" dual-drive woofer. According to Infinity's literature of the time, the QLS uses a phase-aligned passive crossover network (see the first link below) and is (was) capable of 18Hz to 32KHz +/- 3db response. Several versions were produced with black or veneer baffles, paper or poly Watkins woofer cones and possible variations of the Philips AD5060/W8 mid-bass coupler.
The intent of this thread is to provide information for the enthusiast who has the opportunity to own and refurbish these fine speakers.
Photo Courtesy Bobby Shred's QLS1 webpage
Infinity-Classics.de Quantum Line Source website:
http://www.infinity-classics.de/mod...ne-Source-QLS-1/body_quantum_line_source.html
Bobby Shred's Quantum Line Source website:
http://bobbyshred.baberuthband.co.uk/infinity/qls.html
Cdfac's "Running a crossover rebuild parts list by ya"
http://www.audiokarma.org/forums/showthread.php?t=215773
Cdfac's "Keeping another pair of QLS1's alive"
http://www.audiokarma.org/forums/showthread.php?t=166374
Ken Boyd's "Best way to bi amp my QLS1's?"
http://www.audiokarma.org/forums/showthread.php?t=269529
Thedelihaus's "Watkins woofers, what's so special about them?"
http://www.audiokarma.org/forums/showthread.php?t=115775
Geoff727's "Watkins woofer white paper"
http://www.audiokarma.org/forums/showthread.php?t=276032
Banffskiing's "QLS1 restoration project"
http://www.audiokarma.org/forums/showthread.php?t=71339
Meridian's "Watkins woofers in the Quantum line"
http://www.audiokarma.org/forums/showthread.php?t=87469
JT45's "Help restoring QLS1's"
http://www.audiokarma.org/forums/showthread.php?t=317580
JT45's "Infinity QLS1 recapping?"
http://www.audiokarma.org/forums/showthread.php?t=341905
JT45's "Infinity QLS1 recapping with pictures!"
http://www.audiokarma.org/forums/showthread.php?t=387573
Bucky Badger's "Opinions on Infinity QLS speakers anyone?"
http://www.audiokarma.org/forums/showthread.php?t=383963
Kencat & Charivari's "EMIT tweeter diaphram repair how-to"
http://www.audiokarma.org/forums/showthread.php?t=65571
JT45's "EMIT repair with pictures!"
http://www.audiokarma.org/forums/showthread.php?t=387976
JT45's "cleaning those pesky pots on QLS1's"
http://www.audiokarma.org/forums/showthread.php?t=385996
JT45's "Infinity Quantum Midrange repair with pictures!"
http://www.audiokarma.org/forums/showthread.php?t=398687
Mid-Bass coupler AD5060/W8 specs
http://www.classicspeakerpages.net/IP.Board/index.php?showtopic=4320
Link to Rick Cobb's foam surrounds for Watkins 12" woofers (no affilliation), recommended
http://www.ebay.com/itm/BEST-Speake...pt=Vintage_Electronics_R2&hash=item519f4f259b
or contact him at rcobbattampabay.rr.com with your needs
If you come accross other links please add them! :thmbsp:
The Quantum Line Source was Infinity's largest speaker of 1976, a 4-way 17 driver tower consisting of 8 front firing EMITs (Electro Magnetic Induction Tweeter) + 1 rear firing EMIT, 6 soft dome midrange drivers, 1 mid-bass coupler driver in a tube TL alignment and 1 Watkins 12" dual-drive woofer. According to Infinity's literature of the time, the QLS uses a phase-aligned passive crossover network (see the first link below) and is (was) capable of 18Hz to 32KHz +/- 3db response. Several versions were produced with black or veneer baffles, paper or poly Watkins woofer cones and possible variations of the Philips AD5060/W8 mid-bass coupler.
The intent of this thread is to provide information for the enthusiast who has the opportunity to own and refurbish these fine speakers.
Photo Courtesy Bobby Shred's QLS1 webpage
Infinity-Classics.de Quantum Line Source website:
http://www.infinity-classics.de/mod...ne-Source-QLS-1/body_quantum_line_source.html
Bobby Shred's Quantum Line Source website:
http://bobbyshred.baberuthband.co.uk/infinity/qls.html
Cdfac's "Running a crossover rebuild parts list by ya"
http://www.audiokarma.org/forums/showthread.php?t=215773
Cdfac's "Keeping another pair of QLS1's alive"
http://www.audiokarma.org/forums/showthread.php?t=166374
Ken Boyd's "Best way to bi amp my QLS1's?"
http://www.audiokarma.org/forums/showthread.php?t=269529
Thedelihaus's "Watkins woofers, what's so special about them?"
http://www.audiokarma.org/forums/showthread.php?t=115775
Geoff727's "Watkins woofer white paper"
http://www.audiokarma.org/forums/showthread.php?t=276032
Banffskiing's "QLS1 restoration project"
http://www.audiokarma.org/forums/showthread.php?t=71339
Meridian's "Watkins woofers in the Quantum line"
http://www.audiokarma.org/forums/showthread.php?t=87469
JT45's "Help restoring QLS1's"
http://www.audiokarma.org/forums/showthread.php?t=317580
JT45's "Infinity QLS1 recapping?"
http://www.audiokarma.org/forums/showthread.php?t=341905
JT45's "Infinity QLS1 recapping with pictures!"
http://www.audiokarma.org/forums/showthread.php?t=387573
Bucky Badger's "Opinions on Infinity QLS speakers anyone?"
http://www.audiokarma.org/forums/showthread.php?t=383963
Kencat & Charivari's "EMIT tweeter diaphram repair how-to"
http://www.audiokarma.org/forums/showthread.php?t=65571
JT45's "EMIT repair with pictures!"
http://www.audiokarma.org/forums/showthread.php?t=387976
JT45's "cleaning those pesky pots on QLS1's"
http://www.audiokarma.org/forums/showthread.php?t=385996
JT45's "Infinity Quantum Midrange repair with pictures!"
http://www.audiokarma.org/forums/showthread.php?t=398687
Mid-Bass coupler AD5060/W8 specs
http://www.classicspeakerpages.net/IP.Board/index.php?showtopic=4320
Link to Rick Cobb's foam surrounds for Watkins 12" woofers (no affilliation), recommended
http://www.ebay.com/itm/BEST-Speake...pt=Vintage_Electronics_R2&hash=item519f4f259b
or contact him at rcobbattampabay.rr.com with your needs
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