Converting a pair of Magnepan LRS+ for biamp use with a dspNexus DSP crossover

0 Members and 1 Guest are viewing this topic. Read 1253 times.

HAL

Just picked up a pair of used Magnepan LRS+ speakers with the upgraded Magnepan stands.  These will let me use the LRS+ vertically with the open baffle 1x12 subs as stands to raise them to ear height as I did with the LRS.

Will take modification pictures to convert them from passive crossover to direct drive for biamping.
« Last Edit: 31 Dec 2024, 10:45 am by HAL »

HAL

The LRS+ are in the lab and ready for modification for planar direct biamp drive.

First will be using Superior Electric 30A 5-way binding posts to replace the original connectors and bypass the internal passive crossovers.

Then will be time to use the dspNexus 2/8 for the calibrated mic to make new measurements and do speaker correction and bass management using the 1x12 open baffle sub modules as speaker stands as for CAF2024.




HAL

Time to work with the Magnepan LRS+ while waiting for the second LRS speaker to arrive.

A pair of moded FOSI ZA3 amps set for Monoblock mode with XLR Input.

The dspNexus 2/8 is just running as an 8 channel DAC until measurements are done.



HAL

The LRS+ with the Magnepan upgraded stands are on top of the 1x12 modular open baffle subs.  A pair of Orchard Audio Starkrimson Monoblocks is driving the LRS+ speakers passive crossovers.

This height will help with on axis measurements to get ready for the speaker correction data.





HAL

The LRS+ driven by the Orchard Audio Starkrimson Monoblock amps and the moded FOSI ZA3 amps in monoblock mode driving the 1x12 modular open baffle subs.

The 1x12 modular subs are GR-Research SW-12-16FR's driven as normal subs with EQ for flat response.

The DSP crossover, speaker correction and bass management are done in the dspNexus 2/8 with the AK4493S DAC's.



HAL

The LRS+ measurements are done at the listening position and the first set of speaker correction and bass management is running on the dspNexus 2/8.





HAL

The LRS+ have now been modified for direct connection to the planar drivers for biamping or triamping with subs.  This is a totally reversible modification.















HAL


HAL

The LRS+ mod kit is complete for both speakers.

Time to wire the amps and then start the measurement process.




mix4fix

  • Volunteer
  • Posts: 2484
  • I reject your music, and substitute my own.
Is removing the fuse a good idea or bad idea?

HAL

Not a good idea since it protects the tweeter ribbon foil from overcurrent and failure.

The new 2.5A Fast Blow fuse holder is under the connector plate.

HAL

The pair of LRS+ with the passive crossover bypassed is placed on the 1x12 open baffle subs.  Triamping the system with Orchard Audio Starkrimson Monoblocks on the woofer and tweeter planars and FOSI ZA3's as monoblocks on the 1x12 open baffle subs.

The standard Danville Signal dspNexus 2/8 is the control center and DSP crossover for speakers.

Running speaker and room response correction in the DSP.