Those !@^R%!# attenuators are great!!
Sorry for the thread title, but I decided to spank together another ladder attenuator last night (in just one hour!) from a switch I had in the drawer for about three years. I have made a few back then, but learned a lot to make them even better (and simpler, read below the picture) in the meanwhile.
I just forgot how much detail is preserved at low level setting with a proper attenuator! It just occurred to me how I have been conditioned by the lack of detail (that increases by decreasing the volume) of a normal pot that it seems with the ladder that the lower I turn it the more detail is revealing. [
] So....ever wondered why the more you turn up the volume of your system the better it sounds? Well it will always be of course [}
], but now I hear punchy bass dynamics and acres of depth even at low volume!
For those interested I have some tables with values for 10K, 20K, 25K, 50K, 100K and 250K resistor values. I also have some series attenuator resistor value charts, but due to the inferior quality of these (but still a million times better than any potentiometer!!) I don't specialize in these type of attenuators...
The one I made yesterday is a 20K ladder attenuator with a four deck 24pos. Elma switch. Still needs to be placed in an enclosure or preamp or integrated amp. It's not as beautiful as I've seen them here and there, but it works just the same:
What never ceases to amaze me is that even though there are at least 10 steps that use the same resistor value for Rin many builders populate all the contacts with resistors!?? You may notice that it seems like there are resistors missing on my attenuator? They do! You can simply parallel all these contacts so that all these positions use just this single resistor! This also saved quite some time, because I do match all the resistors for the left and right channel very accurately.
I also made a few odd values like 17,5K by using the 16K of the next step and just link a 150R resistor to the previous position! That way I got a REALLY nice linear impedance and a REALLY nice logarithmic characteristic. Actually it is almost like there are no steps at all!
------X-max. can be several meters on any driver, too bad it can be done only once...------
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Pics can help a lot to diagnose something from any place on the globe...
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