To close the loop on this (pun intended) I discussed with the owner of SoundSculpture, maker of SwtichBlade GL and other cool products. Here is answer. Quick version is that the SBGL does not need any DI or ReAmp boxes to connect a guitar, a line level device such as the H9000 or a guitar amp FX loop. The SBGL does have some headroom bandwidth, which is completely manageable and only deters unsophisticated users. I guess what I’m thinking now is to have one FX Chain with IO set at -10dbV for the FX in front of the guitar preamp (form guitar) and and 3 FX chains set at +4dbU for line level coming from FX loops and other guitar preamps (TriAxis).
From Ken @ SoundSculpture
There are always 2 things to consider when interfacing a guitar to anything (or anything to anything). One is the level of course and the two common levels are as you mentioned, -10 and +4. -10dBv is considered “instrument” level and is typically the level seen by a guitar output or the output of a common stomp box guitar effect. Line is simply a signal that is about 12dB hotter. The level of a signal is not related to the other thing that needs to be considered, namely the impedance which is essentially the “drive” capability of a source. There is only one place where impedance is of concern here and that is the output of a guitar which has very little “drive”. This is not to be confused with level.
So to answer your question, the GL will “buffer” the guitar signal, which is what you want, although will not change the level. From there, the GL output can go directly into the h9000r with that unit set to -10dBv (instrument level) so it can use the lower signal level of the guitar. The output of the h9000 should also be set to -10dBv so the level coming out of the unit is the same as the level going in (guitar level). An output from the GL can then be plugged directly into your amp and it will also see a guitar level signal.
No reamp is needed.
Hope that helps.