audio with realistic timbre
 

A DIY series stepped attenuator (3)

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The resistors. Place them in order to be used. I use 0.1% tolerance however 1% tolerance will do fine (practice). Go for the best...?
Each resistor is bent before mounting. One lead a bit higher then the other. You also can determine each resistor's direction by keeping the tolerance marking at one side.
The solderlugs of the switch are turned 45 degrees with a pair of pliers, so that the eye-lets face outwards. This will ease up mounting the resistors. I've mounted the resistors at the innerside of the decks, but it is also possible to mount them on the outside. As you can see, the return lead is kept under the resistor to prevent a "short circuit".
The first resistor is soldered at one lead only, putting the second in place. Than these are soldered together and so on. The leads are cut to length when soldered although this is not supposed to be done after soldering...So cut carefully!
One deck ready! Start at step one with zero ohm and increase in value as you go round. The source is put to step 24, ground to step 1 and the selector to the amplifying stage. This way, at step one, the source will "see" full impedance while creating the maximum attenuation for the amplifying stage.
Ready! This way, the switch's dimensions are kept to a minimum and the tolerance between the two decks will be 0.1% or less!! No "normal pot" will have such specs!!

As you may have noticed, I used more common values in stead of the E96 values as mentioned in the schematic. This really works fine and is done because my supplier had only these values at 0.1%... Go for the best and stick to the mentioned values in the schematic!!
Good luck!

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