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LX521 Linkwitz Lab Open Baffle 4-Way Kit, PAIR

Sale Price: $1,443.42
Compared at: $1,603.80
You Save: $160.38
Product ID : LX521
Manufacturer: Seas Prestige
Weight: 126.00 lbs
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"Magic" LX521 Linkwitz Lab 4-Way Open Baffle Speaker Kit - Drive Units Only
Price shown is for a PAIR

The LX521 is a full scale DIY speaker design from Siegfried Linkwitz of Linkwitz Lab. Also see the more compact LXmini Speaker Kit.

Madisound is offering the drivers, required inductors, and your choice of capacitors at a 10% discount off the regular price. For current Orion users that already have 4 pcs of the L26RO4Y woofer, you have the option of purchasing this kit without those drivers and still receive the discount. 

This Kit Includes:

4x Seas 27TFFNC/G (H1396) 1" Textile Dome Tweeter

2x Seas MU10RB-SL (H1658-04) 4" Curv Cone Upper Midrange

2x Seas U22REX/P-SL (H1659-08) 8" Curv Cone Lower Midrange

4x Seas L26RO4Y (D1004-04) 10" Aluminum Cone Woofer

Also Available:

1x miniDSP 4x10 HD Digital Signal Processor  - available with 10% discount from the drop down menu

1x LX521 Flat Pack cabinets - click on live link for information and to order

2x Madisound 4.0mH 19 awg Air Core Inductor + 2x ClarityCap ESA 12.0 mfd 250V Polypropylene Capacitor (required if building original LX521 w/ ASP)

About the LX521 from Siefried Linkwitz:

"For many years now I have refined, lived with and enjoyed the ORION (2002) and PLUTO (2005) loudspeakers. 

I have learned that the loudspeaker's radiation pattern and placement in the room are more important than the acoustics of the room.

Ever since I started building loudspeakers with cone-type drivers on open baffles several decades ago, I tried to find the optimum shape for those baffles given the drivers available. For ORION the drivers were selected primarily for their volume displacement and low distortion capabilities when used in a 3-way, active system. The LX521 evolved from experimentation with minimal width baffles, which can provide a more uniform dipolar radiation pattern at higher frequencies, if also suitable drivers are available. Inevitably this leads to a 4-way design, which I mostly tried to avoid in the past. 

The shape of the midrange/tweeter baffle was arrived at empirically for the chosen SEAS drivers and after many acoustic free-field measurements. The two SEAS woofer drivers are housed in a V-frame baffle, which exhibits reduced resonance above the operating range of the woofer and some force cancellation. 

A bridge over the woofer isolates the midrange/tweeter baffle from woofer cabinet vibrations. Woofer and midrange/tweeter baffles can be angled independently from each other. The bridge could also be built taller and the midrange/tweeter baffle tilted downwards to aim at the listener in front of a mixing desk. The woofer baffle must rest on the floor for ground plane reinforcement of its output.

The LX521 Analog Signal Processor splits the broadband line level input signal into woofer, mid and tweeter frequency bands. It equalizes driver and baffle response for each channel and filters it with LR4 response. The midrange signal is split after the power amplifier by a passive crossover filter into lower mid and upper mid driver inputs.

Frequency response on upper midrange axis and horizontal dipolar response in the frontal hemisphere are designed for neutral timbre of the the stereo phantom scene, when the loudspeakers are placed in the room as suggested. The aural scene is rendered with clarity and detail, both spatially and tonally."

Full documentation on the LX521 can be found on the Linkwitz Lab website.

Shipping Charges:
  • Due to the relatively heavy weight of these drivers (and cabinets if selected), the shopping cart may not be able to provide an accurate shipping cost for you at checkout
  • Proceed with checkout and select "If no shipping estimates are displayed you can request a shipping estimate. - $0.00", we will contact you with shipping options prior to processing and shipping your order
  • Madisound Shipping Policy


Seas 27TFFNC/G (H1396) 1" Textile Dome Tweeter

Seas MU10RB-SL (H1658-04) 4" Curv Cone Upper Midrange (FU10RB H1600-08 shown)

Seas U22REX/P-SL (H1659-08) 8" Curv Cone Lower Midrange

Seas L26RO4Y (D1004-04) 10" Aluminum Cone Woofer


Madisound is no longer producing the LX521 Analog Signal Processor as future versions of this design will only incorporate the miniDSP 4x10 Hd as the signal processor. If you prefer the ASP version, please visit the Linkwitz Lab website for info on building your own or sourcing it through another channel.

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