Jaded Faith
Well-known member
I am re-posting this to help others and document the discussion started in the thread at http://mtsforum.grailtone.com/viewtopic.php?p=125114#125114.
There are an incredible number of ways to set the MTS system up. Proper gain staging has everything to do with the response and feel the amp and modules provide. The catch with this system is the large number of user variable points to change the level. You have a gain pot, a module level pot, an effects level, an output pot (on the RM4) and a Master volume on the power amps. With great flexibility comes great potential to ruin or improve the tone and feel.
How high you set the module level can be more important than how loud you set your Master volume on the amp for pushing the power section. Setting it too low will choke or starve the preceding stages. Doubt me? Try this test:
Put your multimeter on DC voltage and place the black probe into the common and the red into any of the bias points. With the amp on play you should have your normal bias setting, say 32mV. Now set your gain on the module at 11:00 and the level at 9:00. Put the amp Master at around 9-10:00. Start chugging a palm muted open E chord. Watch the meter read higher, probably about 49mV.
Now start cranking the module level and keep going up to wide open. Watch the meter as you do it. You will wind up around 160mV easy. This is the impact of the module level in how hard you hit the power amp. The Master on the amp will impact this, but not as easily as the module level. That has a direct impact on feel.
Think of all the times someone complained their MTS amp didn't feel like a "Brand XXX" amp. With less spots to adjust the level (in place of some of our volume pots there are preset resistive divider network in those amps, meaning a choice has already been made for you).
This is also what is impacting those comparing the RM4 module level to the level they would use in a combo or head. There's an additional output level on the RM4 providing another point to alter this balance.
There are an incredible number of ways to set the MTS system up. Proper gain staging has everything to do with the response and feel the amp and modules provide. The catch with this system is the large number of user variable points to change the level. You have a gain pot, a module level pot, an effects level, an output pot (on the RM4) and a Master volume on the power amps. With great flexibility comes great potential to ruin or improve the tone and feel.
How high you set the module level can be more important than how loud you set your Master volume on the amp for pushing the power section. Setting it too low will choke or starve the preceding stages. Doubt me? Try this test:
Put your multimeter on DC voltage and place the black probe into the common and the red into any of the bias points. With the amp on play you should have your normal bias setting, say 32mV. Now set your gain on the module at 11:00 and the level at 9:00. Put the amp Master at around 9-10:00. Start chugging a palm muted open E chord. Watch the meter read higher, probably about 49mV.
Now start cranking the module level and keep going up to wide open. Watch the meter as you do it. You will wind up around 160mV easy. This is the impact of the module level in how hard you hit the power amp. The Master on the amp will impact this, but not as easily as the module level. That has a direct impact on feel.
Think of all the times someone complained their MTS amp didn't feel like a "Brand XXX" amp. With less spots to adjust the level (in place of some of our volume pots there are preset resistive divider network in those amps, meaning a choice has already been made for you).
This is also what is impacting those comparing the RM4 module level to the level they would use in a combo or head. There's an additional output level on the RM4 providing another point to alter this balance.