Elma switches

[AndrewGM]

I've picked up two ELMA switches which are pale blue
that look and fee very high quality. I'v seen them in other peoples
passives and in gainclones.

The first has an action of.... on / off and has 8 silver plated solder tags ( 4 groups of two ) and four slim posts in the centre.

The second has and action on / off / on ( 3 positions )
It has 6 equally spaced silver plated solder tags and has two slim
posts in the centre.

Which one will be good for a selector switch for a passive pre amps please ?
How do you wire them, which tags are for what ?

I only want CD and AUX so have I bought the right things ?

Sorry for the basic terminology

Andrew

[Nuuk]

Andrew, if you haven't seen it already, this may be of interest.

You need to use a multimeter to see which tabs make contact with each other when the switch is in a certain position.

Use the 3-way switch (you could use the third position for nothing connected ie mute.

The two pins in the middle are the output pins, the two banks of three are for inputs. Just make sure that you match up left and right channels.

You could of course use the 8-way switch, and switch both signal and grounds!

[AndrewGM]

Nuuk Thanks

I'm not sure what you mean re switching grounds - 8 way switch but I do understand the other explanation.
Presumably the two centre ' outs ' will go to the
strepped attenuator ' in's ' and away I go.
Great

I ordered a DACT style stepped att with surface mount resistors in 10 K.
I'm going to use it on a 3886 based gainclone when the boards
eventually get here and in the meantime on an old mosfet
project I've had for years.
It was originally a HUGE £450 dual mono Denon integrated from the 80's which is stripped of it's pre amp and any other crap I could get rid of. ( cost me £25 !! )
I've changed all the critical bits to Rubycons and 1 % metal film res, short silver cables in and out, better bridge rectifiers, large Aerovox caps and it measured square at 100 watts each on a friends Oscilliscope. It also drove Isobariks loud too - which was an eye popping test for an old amp !!
The point of this desription is : would a 10 k pot also work
with this monster as say, an integrated ? ( pot in amp )

Thanks for the link - I had not seen it before.
It's a big site isn't it ?

Many thanks

Andrew

[Nuuk]

The point of this desription is : would a 10 k pot also work

It will "work" but the question is how well?

[AndrewGM]

Will work - but do you mean it wil either be very loud or very quiet at low settings and need turning right up to the top
or just sound quality, soundstage, detail, imagery etc etc

In a 3886 Gainclone based system will it be fine ?
10 K seems to be the value of choice on other posts

I guess I can just keep buying them until I find the right one...
More expense !!

Thanks

Andrew

[Nuuk]

10K is the value that is required for inverting GC's. For a non-inverting GC you can go higher, eg 20K 50K.

It's all about impedance matching with what goes before and after the pot.