That's not true. I used a GCX for years, sounded great. What you're suggesting is that any piece of equipment that has buffering is no good w/ a buffered guitar? That excludes a lot of equipment.
too some extent it is true and exactly why the audio switcher is used. to eliminate the loading of all the buffers in a chain. with no OBEL onboard and a buffer, sure you could run whatever buffered effects you want in the chain, but you are only loading down your signal(thanksRR) and altering your tone. it becomes muddled in the interaction of buffer to buffer interplay. when you move to an OBEL onboard the guitar without an on/off switch almost the same scenario, but when you put the switch onboard also, you get a single buffered output of the guitar, and a second loaded down effects loop which creates two different tones from the clean and effected signals. when you place an audio switcher(like a gcx) in the effect loop and individually have each one true bypassed out, you will get the same signal on both sides as there is no buffer to buffer interplay. they are true bypassed out of the signal. that said, what strummin states is true, you defeat your efforts placing a buffer in the guitar when using the buffered input of a gcx to true bypass the buffers in your pedals. with the onboard buffer on the guitar the gcx unbuffered input is ideal. without an onboard buffer, the buffered input of the gcx should be utilized. this is how peter cornish's effects systems all are, buffered at there inputs and the guitar cable plugged into it. but jerry and the boys knew that the cable capacitance and resistance of the cable created a filter and sucked some tone, so the buffers were placed onboard the guitar as close to the output signal of the pickups as possible. and while jerry didn't start there, he eventually got there having just the one buffer in his guitar that completely ran his signal unhindered by any buffers inline. that produces the cleanest, strongest unhindered signal possible to the preamp. even if you do everything else but don't put a buffer in your guitar, you deal with the guitar cable from guitar to amp. use a small one or a good one because they all have some sorta capacitance and resistance. no matter how small it is, it's there.
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