I was recently comparing several powered speaker systems, but didn’t like the audible *Pop* I heard when plugging and unplugging the 3.5mm headphone jack into each of them. I made a switchbox that eliminates this pop by switching the one input (my mobile phone) to any of the four outputs. I didn’t have the right rotary switch at the time I built it, so it actually has two knobs that select where the input signal goes, meaning I can have two systems playing at the same time. Alternately, the box can be used to switch either of two inputs selected with one knob to either of two outputs selected with the second knob. Even more alternately, the box can be used to switch four inputs to a single output.
I few days later, after I purchased(!) the correct rotary switch, I built a second switch box. This one has stereo logarithmic-taper potentiometers wired as voltage dividers, effectively acting as independent volume knobs on each channel. With these volume controls, the playback levels of speaker systems with different gains can be matched, for ease of comparison.
Cool! I find that the most important thing in comparing amps and speakers is having a really good source. I have a non-oversampling, digital-filterless, battery-powered DAC (an Ack dAck! 1.0) I’d be happy to bring in one night, or even lend you for a little while.
Any chance that the “upgraded” version of the 2 is available for purchase? If not, do you have suggestions as to similar available products that you’d recommend? Thanks.
Unfortunately, its not available for sale, but I can give you some directions/advice on how to build your own. If you’re not up for the DIY solution, commercial alternatives do exist. For example, OSD Audio’s 6 or 4 channel model SSVC6 or SSVC4, and the Niles/OSD 2 channel model SSVC2.
Just found your audio box as i am looking to do something similar myself.. You said to start with you did not have the right encoder but later got one… What type was it? I am looking to build a simple box which can flick between two audio sources… I am totally new to this so any help would be greatly appreciated especially on wiring the rotary as this is baking my noddle a little
You can use any dpdt switch like this classy one from Radio Shack and three 1/8″ headphone-cable type jacks like this. It’ll help to have a multimeter to get the wiring soldered to the correct toggle switch pins and jack contacts!