I'm running stereo outputs from my MXR stereo chorus into A and B inputs on the VL Amp Selector. Following the instruction manual, I have outputs 1 and 3 from the Selector connected to the two amps I want to reflect the stereo chorus, and a third amp connected to output 2 for which I want no chorus. Problem is that when I use both stereo outputs from the MXR Stereo Chorus only two channels of the amp selector function--outputs 1 and 2. Outputs 3 and 4 have no signal. This doesn't accord with what is described in the instruction manual. If I use only the mono out from the MXR Stereo Chorus, then all three amps will work. What is the problem here? Please advise on how to use stereo effects while running three amps simultaneously. Thanks!Unfortunately, what you are trying to accomplish is impossible, for two reasons:
1. You cannot feed an effect-processed guitar signal - in your case a stereo chorus - into any device - in this case a VL Amp Selector - and then expect to get an unprocessed signal from any of that device's output jacks. All it has to work with is the incoming "preprocessed" signal you're feeding it; there is no way the Amp Selector can remove the chorus from that signal before sending it to any particular output which, in your case, would be Output 2.
2. Here is an excerpt taken from Page 4 of the Amp Selector manual under the Connections section:
If you are going to use two guitars (or the other channel of stereo effects) simultaneously with different amps, you can connect the 2nd guitar into Amp Selector Input-B. If you do this, the Input-A instrument will only access amps 1 and 2, and the Input-B instrument will only access amps 3 and 4.
In other words, whatever is connected to Input A gets routed to Outputs 1 & 2 only, whatever is connected to Input B gets routed to Outputs 3 & 4 only, and if you only have a signal connected to Input A, it gets routed to all 4 outputs, so based on your description your Amp Selector appears to be working exactly as designed. When you use the stereo inputs, you're hearing one channel of your stereo chorus from Outputs 1 & 2 and the other channel should be at Outputs 3 & 4. Again, if you are using both inputs, there is no way you can get an unprocessed (no chorus) signal from any of the Amp Selector outputs.
However, after double checking your connections, if you are still not hearing anything from Outputs 3 & 4, you may have a bad cable connected to Input B. Easiest way to test this is to just swap out the A & B Input connections. If you now have a signal at Outputs 3 & 4 but nothing at 1 & 2, the cable is the problem. If you still have no signal at Outputs 3 & 4 it's not the cable, but either something is wrong with the Amp Selector's internal Input B signal routing, or your MXR Chorus isn't producing a stereo signal. You can check the latter by simply connecting both channels of the chorus directly to two amps. If that works, then test the Amp Selector by connecting two guitars to Inputs A & B and see if Guitar B is sending a signal to Outputs 3 & 4. If not, you're next step will be contacting Voodoo Lab Customer Support.