Hi, just got my new Roland R05 this afternoon and found there is a hidden menu you can access by pressing the "A<>B/Split" button together with the "Menu" button.
It will display what looks like the normal menu screen but with an extra option choice #8 that says "Special Setup".
When you select that option #8 it takes you into a bunch more parameters that you can set and fiddle with.
The most useful one for me at the moment is turning off the "Record" red led light whenever you go into record mode. That's good for stealth mode recording in dark places so it won't catch attention.
There is also a mic gain setting which is default I think to 18DB gain. You can adjust it in fixed increments up or down a litlle bit. I think the next higher gain step jumps to 28DB gain, the next lower setting is like 13DB gain (I cannot remember as I don't have it in front of me now). There is also a setting called "Mic Bias" which is default set to *0.9. I have no idea what it is for except my guess is how much battery voltage it sends to the mic plug in power.
Many other adjustments are in there to tweak reverb timings and all that too, there's more too but I just cannot remember the list. But there you have it. Nice easter egg they gave us.
Preamp noise? I have no conclusive opinion yet compared to my Sony PCM-M10 and PCM-D50 mic-in preamp noise levels. But the R-05 seems to be just as quiet by my initial impressions.
No, I have not tested line-in overload levels. I don't use line-in currently.
Updated: to correct menu selection choice #6 to #8 for the "Special Setup" after I looked at it again. Also there is not adjustments for reverb settings, but rather the "Auto Record Start" parameters instead as well as the AGC level and attack settings.
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