Marantz HD770 4 way Crossovers

AllenB

Moderator
Paid Member
2008-10-18 11:31 am
Peterma, you don't say what your problem building them is. Is it finding parts, reading the schematic, soldering?

Some assume expensive. The coils beside the drivers are high resistance. This can mean cheap, even a spool of cheap thin hookup wire might do the job :p . The caps don't have to be polys, electrolytics can sound very good. The L-pads can be replaced with resistors.

What parts d you have lying around that might be useful.
 

Lojzek

Member
2012-02-10 12:12 pm
Croatia
Wind your own coils?

Perhaps we can assist in doing your own coils. I am positive that with help of a coil calculator, we can predict diameter and inductance within a couple of percent from the original value. If there were any issues finding right magnet wire for the higher dcr inductors, adding a resistor in series would solve it.

How much does awg 18 and awg 27 magnet wire cost in Australia?
 

AllenB

Moderator
Paid Member
2008-10-18 11:31 am
Retail, that's 25ga and 19ga on the right, 57m and 14m in length.

I get quality double enameled unused magnet wire from a motor rewinder who sells me the ends of the spools for next to nothing because he doesn't like to use them.
 

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Lojzek

Member
2012-02-10 12:12 pm
Croatia
There is also the option of purchasing ready made cheap Chinese crossovers employing iron core inductors. Modifying these to meet the original marantz values would not be hard, some caps might fit also. The excess wire from one could be used to increase the inductance of another.