Simple Symetrical Amplifier

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Hi Marc

nichrome wire is made of Nickel and Chromium, and has a relatively high resistivity, and therefore resistance, depending on diameter.
Look here for typical values: wires.co.uk : Bare Nickel Chrome / Nichrome Section

I have had good results with Costantan wire which has a better TC than NiCrome - this wire sounds better that any commercially available resistors I have tried. Ideal for low values. I have been using this wire in my amps as o/p degeneration & o/p resistors / fuses for years.

wires.co.uk : Copper Nickel / Constantan / Eureka Section

But I am informed that manganin is considered better that constantan: even lower TC and also much less nickel in the mix and thus less "magnetic" but I didn't try it yet.

WIRES.CO.UK MANGANIN
 
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My coils of constantan are more than 5 years old and the appearance has not changed in that time.

NAIM uses same solution for years

;)
 

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:up::up:

120mm fits perfekt in a modu 4U/300 with 165mm internal height, giving a nice chunky look :D
and those heatsink should make it indestructable in any load ;)

It can be nicely installed in 3HU (132 mm) as side external heatsinks as well. 120mm x 170 mm SSA BIGBT HP PCB plus 400VA/120 mm (diameter) x 80 mm toroidal transformer, fits perfectly on a 132 mm x 300 mm x 40 mm Fischer heatsink as compact all-in-one amplifier module. ;)
 
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OK as you wish, but all the bigs caps are soldered at the end of construction, when all other components are already installed. All under PCB BJT's must be mechanically fixed to flat firm surface and than soldered to PCB, after low profile components (diodes, LEDs resistors, etc.). SSA "construction work" (installation) manual will follow. :D

It all depends on priorties one demands to follow. Major one ahead of this design here is to maintain high bandwidth results from protoboard measurements. It will be PITA to get there but anyway ... ;)

P.S. This will be double sided PCB and big caps are 50 mm height.
 
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ARGGGG double side pcb board....a pity to etch at house....so it seems that i need to spend many time on eagle for sigle side way.... with more room needed. LC i suppose that BIGBT HP in lowaer rail voltage count same parts number as your hightest version...only value changing inside????

Marc

Note : NJL4302DG arrived today so yet i have 5 couples NJL4281DG/4302DG for SSA_TT_35V
 
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