This may give some insight on what each tube does the effects the next tube ect:
V1 is the vital initial gain and tone for both channels .
V2 Is your cascade overdrive tube fed from v1 , this can be a challenge finding your crunch flavor .
V3 is the Equalizer recovery , use your ears turning the treble- mids and bass to see how you like it for your guitar.
V4 Effects loop send return , its critical if your using it like me, a too brite tube can cause a smearing sound and the overdriven chorded notes are covered up !
Phase inverter 12ax7 , this tube will distort into mush by the gain in channel 2 if wrong tube is there.
I suggest for the PI use a balanced sovtek 12ax7 lps to have a chance getting channel 2 close to where it can be !
The channel 2 OD tube I use a NOS Phillips labeled EI 12ax7 its a Yugoslavia grey smooth long plate with gain and crunch !
I could not get a decent Sino tube to work very well except if you want mush at gain 6.5 !
A EH gold pin 12ax7 did well gained up into crunch , the Tungsol was ok but to bright and spiked highs on my single coils was a no no.
I discovered the FX v4 also gained up and equalized the frequencies or badly over pushed the highs when the wrong tube was there, a TAD Russian 7025 was nicely doing the job well.
I have the 12ax7 black plate family and smooth overdrive was there but I needed crunch and highs.
I like the tube tone and round notes the Russian tubes have and the Genalex 12ax7 gold has better gain than a 12ax7wa but both have it going on where others were more hi fi like !
I had good luck thru out several years on my R30 and no problems !
Have fun and wright down your tube test results because it helps !
V1 is the vital initial gain and tone for both channels .
V2 Is your cascade overdrive tube fed from v1 , this can be a challenge finding your crunch flavor .
V3 is the Equalizer recovery , use your ears turning the treble- mids and bass to see how you like it for your guitar.
V4 Effects loop send return , its critical if your using it like me, a too brite tube can cause a smearing sound and the overdriven chorded notes are covered up !
Phase inverter 12ax7 , this tube will distort into mush by the gain in channel 2 if wrong tube is there.
I suggest for the PI use a balanced sovtek 12ax7 lps to have a chance getting channel 2 close to where it can be !
The channel 2 OD tube I use a NOS Phillips labeled EI 12ax7 its a Yugoslavia grey smooth long plate with gain and crunch !
I could not get a decent Sino tube to work very well except if you want mush at gain 6.5 !
A EH gold pin 12ax7 did well gained up into crunch , the Tungsol was ok but to bright and spiked highs on my single coils was a no no.
I discovered the FX v4 also gained up and equalized the frequencies or badly over pushed the highs when the wrong tube was there, a TAD Russian 7025 was nicely doing the job well.
I have the 12ax7 black plate family and smooth overdrive was there but I needed crunch and highs.
I like the tube tone and round notes the Russian tubes have and the Genalex 12ax7 gold has better gain than a 12ax7wa but both have it going on where others were more hi fi like !
I had good luck thru out several years on my R30 and no problems !
Have fun and wright down your tube test results because it helps !