Congratulations on the purchase of
your new
RANDALL
Amplifier!
We at Randall Amplification appreciate that
you chose our brand of guitar instrument
amplifiers and wish you years of great tone
and enjoyable playing time with our proven
MTS Series.
Please review the safety instructions
below and be aware that the
documentation provided in this manual
references 120volt USA versions of the
models covered. Note that the POWER
listed on the back of the unit should be for
your countries’ power standard.
A M P L
I
F
I
E R S
RM50/RM80
M O D U L A R T U B E C O M B O S
O W N E R S
M A N U A L
*Note that RM20 has same operation as
RM22 (shown) but with only one MTS slot*
1. Channel Selection Switch
(Footswitchable)
2. 1/4” Guitar Input
3. Channel 1 Boost Switch
(Footswitchable)
4. Channel 1 Boost Gain- Controls the amount of tube
overdrive
(Footswitchable)
5. Channel 2 Boost Switch
(Footswitchable)
6. Channel 2 Boost Gain- Controls the amount of tube
overdrive
(Footswitchable)
7. MTS Preamp Module Slot #1
8. MTS Preamp Module Slot #2
(RM22 models)
9. MTS Module Thumbscrew- 2 per Module
10. Channel 1 Boost Level- Controls the amount of
volume increase when engaging boost function.
11. Channel 2 Boost Level- Controls the amount of
volume increase when engaging boost function.
12. Density knob controls the low frequency EQ
response of the power amp section
13. Presence knob controls the high frequency EQ
response of the power amp section
14. Power switch turns unit on and off
15. Switch for Silent/Standby/Live Modes
•
Silent Mode
sends amp signal to XLR output and
mutes speaker outputs- The amp can work
standalone without speaker hooked up (Automatic
when no external speaker connected on Head
versions)
•
Standby Mode
- amp is powered but no output-
Leave in this mode when powering on and off
• Live Mode
- Standard output to speaker or cab.
16. Power cable input for mains connection.
17. Fuse socket
18. Footswitch connection for included footswitch
• 1/4” one button switch for RM20 models
• Multi-pin 3 button footswitch for RM22 models
controls channel selector and Boost function for
each individual channel.
19. External Speaker output 4/8/16
Ω
operation
(
Combo models have internal cord to connect to
internal speaker)
20. Preamp 1/4” line output
21. XLR Direct Recording Output (Speaker Simulated)
22. Power Tube Bias Section (see attached
Document)
23. Effects loop return - connect from output of
external effects unit
24. Effects loop series send - connect to input of
external effects unit
