The Market > Manufacturer News

Magnepan 1.7 dspNexus 2x8 DSP Crossover project

<< < (2/4) > >>

HAL:
Modified the new connector plates with the Superior Electric BP30-10 5-way binding posts.

Next is to rewire the fuses to the tweeter and supertweeter planars for protection.

Hard to find the black 5-way connectors, so went with yellow for the negative terminals.

HAL:
New connector plates wired for 3-way use for the Magnepan 1.7 speakers.

Disconnected the original passive crossover in the 1.7's and will install the new connector plate in the speaker with the open super tweeter for testing.

HAL:
Have the 1.7 passive crossover disconnected to remove it and install the new triamp connector plate.  This also lets me get the driver ready to replace the open super tweeter foil.

The super tweeter driver is the left most two foil traces on the diaphragm.  The DC resistance when working is 1 Ohm.  With the 4A fuse that means that the max input power is 16W rms before it opens.  A big amp is not needed.  Yes, you could series it with the tweeter foil, but that has been done, so time to try something different for direct drive.

This is a case where a transconductance amp like a First Watt F1 or F1J amp would be an idea.  You can also DIY one with Chip Amps.  These are current output amps not voltage output amps like any typical audio amp mostly available.

HAL:
Both passive crossovers in the 1.7's are now removed and replaced with each planar driver having a pair of Superior Electric BP30-10 5-way binding posts on the connector plate.  Wired with 14awg Belden 1309A wire to the fast-on's.

I still have to wait for warmer weather to take the one speaker with the open circuit super tweeter outside to chemically remove the old glue and install the new aluminum foil for the super tweeter on the diaphragm.  Acetone and Isopropanal are recommended for the task.

At least with one speaker fully operational, I can now make farfield measurements of it to complete the DSP crossover.  I have a model of the original crossover design to see what makes sense for improvements.

HAL:
Finally getting back to these speakers.

The three pairs of 3' 14awg speaker cables with locking banana plugs is complete. 

I am beginning to test the three pairs of Orchard Audio Starkrimson monoblocks that were in my room during the ground water problem.  See some residue on the chassis, so time to open them up and check.  Most of the original SMPS took on water, so bought the 300W GaN replacement SMPS to use with them.

The EA dspNexus 2x8 with the AK4499EX DAC's is here and getting it setup with the one working speaker for testing. 

The weather is almost warm enough to take the one speaker with the open super tweeter outside to begin the replacement.  Going to be interesting.

Navigation

[0] Message Index

[#] Next page

[*] Previous page