Are there passive attenuators that don't zero volume and only offer one input ?


I am not sure how many people would like those features, but its worth asking in case someone would try to sell such a thing.

Which is to say it is essential I should think  to be able to zero volume, and have more than one input, do you agree ? 
dbxrecord
This is BS, do your own homework.
The very best is the NSL32SR2S and is the most expensive, second is the NSL32SR2.
The R3 is the cheap one and doesn’t go low enough in volume unless over powered/stressed and won’t last if done so.


First off observe the incivility of language being used in the first paragraph, and the attitude of demeaning.  He would do well to learn to tackle the subject, & not the writer.

Lets look at the subject. The manufacturer Luna inc states  for the NSL32SR2S " low distortion"   , and for the NSL32SR3 " best distortion characteristics "  best,  in my dictionary The Concise Oxford has the following meaning: " of the most excellent, or outstanding, or desirable kind "

The second part of his reply,  its easy to assess that pricing of goods of any business relates to the number of units being sold. Indeed the SR2S is more expensive as a direct result of fewer being stocked and one would have to then think units sold, a weak point in his reply to raise.  Trying as we see, to attribute higher cost, as being better. As example today DigiKey stocking 13611 of the SR3, and just 897 of the SR2S.

but lets go on, he states as we see 
doesn’t go low enough in volume unless over powered/stressed and won’t last if done so.

He refers here to 20 ohms of difference that the SR2S has when powered with 20ma of current, vs  the SR3,  his attribution being needed to go low enough in volume. 

Herein the problem, finally exposed, deep breath ... one does not need to raise current, to achieve low or zero volume with LDR's.  In fact other designs achieve current draw of no more than 3ma total at all volume levels which includes the entire circuit, with the benefit of no stress at all, to the LDR's

Another issue being lowering shunt resistance too low, appeasing to achieve low volume, does nothing,  other than squashes available dynamics in music. It is far better to have a higher resistance to begin the shunt resistance range, with the NSL32SR3 its possible though to have 100 ohms at zero volume, and 56k by mid volume with the shunt pair , and to have  25 mega ohms at zero volume with the series pair and 18k at mid volume.   That though does take quite a bit of design effort.... but it can be done.
Other designers providing LDR attenuators worked this out many years ago how to zero volume, and to provide more than one stereo input,  without using higher current , they even went to the trouble of publishing how to do it, for everyone's benefit.  



I owned the Placette Passive and one of my friends still owns one. They are fantastic. Mine was a 4 input, one output version. My friend's unit is a 3 input, 2 output unit.

I would still have it, except I decided to go to an integrated amp to free up some audio rack real estate.


The S3 ’s are widely all over the place, almost impossible to get few "quad matched sets" to do a Lightspeed properly with close to zero volume low volume, unless they are forced matched with servo feedback arrangement and by over driving some which "raises the distortion substantially" to meet the others which will kill them over a very short period.

NZ shysters
Chris Daley? JAVA ldr passive preamplifier $3.5K!!!!!!


The S3 's are widely all over the place, almost impossible to get few "quad matched sets" to do a Lightspeed properly with close to zero volume low volume, unless they are forced matched with servo feedback arrangement and by over driving some which "raises the distortion substantially" to meet the others which will kill them over a very short period.



Actually the SR3 are better in my experience than the SR2S for matching. There is no need either, to use servo feedback arrangements.
Keeping current 3ma for the whole circuit is the key. Sweeping between lowest volume and highest should achieve variance of just 2.78ma to 3ma , for the entire circuit, encompassing the load of 4x NSL32SR3 

There is no need to go any higher at all, which keeps distortion extremely low, and achieves much better stability with cell resistance. 

R(on) of 20ma per device, or anywhere near that figure, is thus neatly avoided .   





Whatever, why did you start this thread, if you know all the answers