[zyss]

Placette audio active pre (stepped vishay s102, 126 steps)

 

[zyss]

http://www.mfaudio.co.uk/phonebox.htm

 

[Linnenberg]

Incidentally I tumbled over this thread because „palchiu“ posted a picture of our spa1. It seems, that the participants here lumped together discrete stepped volume controls and chip based solutions. It is absolutely clear, that a chip is always a stepped attenuator device, because the uninterrupted, mechanical approach of a potentiometer is impossible to realize. By no means, this implies that they are working in the same way a stepped attenuator build with switches and discrete resistors does.

Not technically and not sonically. Please bear in mind, that resistors in chips are solid state semiconductor devices that do not conduct equally in both voltage directions; their linearity is thus limited to a small headroom. The switches are in fact CMOS transmission gates. Parasitic capacitance and dynamic nonlinearities are unavoidable in chip based circuits.

Linnenberg Audio was one of the first companies employing the Crystal Semiconductor CS3310 in 1994. Soon we had to learn, that the convenience of these chips is bought dearly with sonic disharmonies.

 

[zyss]

Harmony Design Ear909.

 

[Kurotetsu]

I was actually in the market for a volume controller, I decided to invest in a stepped attenuator over a potentiometer because I had heard that they lasted much longer and were completely passive. I wound up getting this:
 
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=190711418106#ht_3690wt_1165
 
I got it yesterday and it works really well. It has plenty of inputs and outputs and the L/R channels stay balanced even at low volume (something that didnt happen with the volume control on my Zero DAC). I haven't done a true A/B comparison between that and my Zero DAC, but I KNOW for a fact that the Zero was amplifying the line level input before it got to my active monitors (which means the signal was being double amped, which I know is bad) because I could increase the volume through the Zero higher than what my active monitors were putting out when I fed the line level input directly into them. That the attenuator can't amplify the signal unnecessarily means that its already better than the Zero's controller. My only complaint is that the volume knob is stiff and not smooth, but I expected that going in. That seller also has a cheaper version that doesn't use Dale resistors, but they appear to be sold out.