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Hi All.

Need a bit of clarification here. I've made an algorithm that connects the left input to both outputs, no other effects. I can't understand the behaviour of the wet to dry mixer and the fx loop, if the loop is set to no sum then the wet dry mixer fades the guitar from the left side to zero, if it's set to bypass then the wet dry mixer appears to do nothing, I don't really get the signal architecture. Looking in the manual I see the signal flow diagram, which makes sense, and the algorithm diagrams but neither of them seem to explain the behaviour I'm seeing. Could someone put me out of my misery? Thanks.

Nick.

I’m going to answer your question in 2 parts. The first part addresses the functionality of the “External FX Loop.” The second part attempts to address your “Wet / Dry Mixer” questions.

The following description of the “External FX Loop” is copied from MIDIWizard’s on-line help:

Effects (FX) Loop Return

How the FX Loop Return signals combine with the guitar input signal are as follows:

Bypass – the FX Loop Returns are off and completely ignored. From the factory, every program in the GSP-2101 has the FX Loop set to Bypass.

Summed – the FX Loop Returns are summed together with the guitar input signal using a 50:50 ratio. Use this setting if you are using a second effects processor to augment the GSP-2101. In this situation, you would connect the FX Send from the GSP-2101 to the input of the second processor and then connect the output(s) of the second processor to the FX Loop Return(s) of the GSP-2101.

No Sum – if plugs are connected to the FX Loop Return jacks, they are the primary signal source and any guitar input is completely ignored. If there is no signal present at these jacks, you don’t hear anything from the GSP-2101. When the jacks aren’t used, No Sum behaves the same as Bypass.

Use the No Sum setting if you have a second effects processor and you want to bypass the analog section of the GSP-2101 (the Compressor, Distortion, Analog EQ, and Master Volume). In this situation, you would connect your guitar to the input of the second processor and connect the output(s) of the second processor to the FX Loop Returns of the GSP-2101.

Now to your questions about the “Wet / Dry Mixer”. You did not provide any clues as to your User Algorithm connections so I used the standard Factory Algorithm 29 “No Digital” to simulate your problem.

Factory Algorithm 29 includes the standard chain of analog effects (Compressor, Distortion, Analog Graphic EQ, Master Volume, External FX Loop, and Stereo Noise Gate). This analog chain is included in all algorithms, whether they are Factory or User Algorithms. At the end of the algorithm chain, Factory Algorithm 29 includes a Wet / Dry Mixer so Factory Algorithm 29 should be identical to your User Algorithm.

I tried various “External FX Loop” settings and played with the “Wet / Dry Mixer”. I could not replicate the problems you are having. I can only conclude that the connections between the modules in your User Algorithm are not correct.