Ron W
Active Member
Here's what just might be the ultimate Marshall Class 5 combo. All circuit mods were done by Lyle Caldwell at Psionic Audio. Lyle is well-known as a modder's modder when it comes to the Marshall Class 5. Here are the stats on this killer Made in the UK, Class 5 combo:
- Marshall Class 5 Version 3 C5-01 combo with low power switch + 3 piece back; this is the final and most desirable of the 3 versions produced.
- Psionic Audio "True Plexi" Mods
- Psionic Audio "Variable Voltage Circuit" (Lyle's take on power scaling)
- Psionic Audio Custom Switchable Gain Mod (not part of "True Plexi" mods)
- Mercury Magnetics MCL5-OS Output Transformer with switchable speaker outputs for 8/16 Ohms
- Speaker upgraded w/10" Celestion Greenback
Be sure to check out Psionic Audio's FB page for a full description of the True Plexi mods with lots of pics. The True Plexi mods are not to be confused with some of the more common DIY Class 5 mods:
https://www.facebook.com/PsionicAud...2759226442415/730513733666958/?type=3&theater
You can also check out this link which shows the Mercury Magnetics OT mod I had Lyle do on this Class 5 that lets you switch between 8/16 ohms as well as run a external cab in parallel with the combo speaker, or an external cab with the combo speaker disabled:
https://www.facebook.com/PsionicAud...2759226442415/773382156046782/?type=3&theater
Here's how Lyle describes the True Plexi Mods on his FB page:
People have asked about these switches. Here goes:
Bright affects both the amount of treble and bass on the High Treble "channel." Left is warmer with more lows, right is brighter with fewer lows.
Channel is a three way switch. Left is the "Normal" channel, right is the "High Treble" channel, and middle is both channels "jumpered."
JTM/JMP:
Left (JTM): both channels share a cathode circuit (more bass for the High Treble channel) and there is no bypass cap across V2a's cathode resistor, for slightly lower overall gain without as much emphasis over 700Hz).
Right (JMP): each channel has its own cathode, with the High Treble having fewer lows, and the bypass cap is on V2a's cathode, for an overall gain increase with more emphasis over 700Hz.
If you wanted to duplicate this package, here's what you'd spend:
Class 5 Version 3 Combo: 350
True Plexi Mods: 275
Variable Voltage Circuit: 100 (when done w/True Plexi mods, otherwise $200)
Switchable Gain: 50
Mercury Magnetics OT Upgrade w/switchable speaker output & Ohm selectors: 250
Celestion Greenback 10": 115
Class 5 C110 Extension Cab: 175
Celestion Gold 10": 175
(2) Class 5 Slip Covers: 70
TOTAL: $1175
The Class 5 in stock form is a bit of a one trick pony, albeit a very good one. However, Lyle's True Plexi mods take it into an entirely different tonal territory. His take on power scaling lets you easily dial in "bedroom" volumes. Want to go to "11"? Just turn it all the way up and it's out of the circuit.
The switchable gain mods give you 3 different (low, high and normal) levels of gain for any given setting.
The 10" Celestion Greenback is a nice upgrade over the stock speaker. The Mercury Magnetics output transformer gives you all kinds of internal/external speaker options, as well as some really nice tone.
The cab is in excellent condition, with just a couple of small scuffs/snags on the lower rear area. Comes with stock tubes (Marshall branded JJ EL84 and (2) Marshall branded 12AX7A's.
SOLD shipped CONUS PayPal friends and family. Regular Paypal add 3%
- Marshall Class 5 Version 3 C5-01 combo with low power switch + 3 piece back; this is the final and most desirable of the 3 versions produced.
- Psionic Audio "True Plexi" Mods
- Psionic Audio "Variable Voltage Circuit" (Lyle's take on power scaling)
- Psionic Audio Custom Switchable Gain Mod (not part of "True Plexi" mods)
- Mercury Magnetics MCL5-OS Output Transformer with switchable speaker outputs for 8/16 Ohms
- Speaker upgraded w/10" Celestion Greenback
Be sure to check out Psionic Audio's FB page for a full description of the True Plexi mods with lots of pics. The True Plexi mods are not to be confused with some of the more common DIY Class 5 mods:
https://www.facebook.com/PsionicAud...2759226442415/730513733666958/?type=3&theater
You can also check out this link which shows the Mercury Magnetics OT mod I had Lyle do on this Class 5 that lets you switch between 8/16 ohms as well as run a external cab in parallel with the combo speaker, or an external cab with the combo speaker disabled:
https://www.facebook.com/PsionicAud...2759226442415/773382156046782/?type=3&theater
Here's how Lyle describes the True Plexi Mods on his FB page:
People have asked about these switches. Here goes:
Bright affects both the amount of treble and bass on the High Treble "channel." Left is warmer with more lows, right is brighter with fewer lows.
Channel is a three way switch. Left is the "Normal" channel, right is the "High Treble" channel, and middle is both channels "jumpered."
JTM/JMP:
Left (JTM): both channels share a cathode circuit (more bass for the High Treble channel) and there is no bypass cap across V2a's cathode resistor, for slightly lower overall gain without as much emphasis over 700Hz).
Right (JMP): each channel has its own cathode, with the High Treble having fewer lows, and the bypass cap is on V2a's cathode, for an overall gain increase with more emphasis over 700Hz.
If you wanted to duplicate this package, here's what you'd spend:
Class 5 Version 3 Combo: 350
True Plexi Mods: 275
Variable Voltage Circuit: 100 (when done w/True Plexi mods, otherwise $200)
Switchable Gain: 50
Mercury Magnetics OT Upgrade w/switchable speaker output & Ohm selectors: 250
Celestion Greenback 10": 115
Class 5 C110 Extension Cab: 175
Celestion Gold 10": 175
(2) Class 5 Slip Covers: 70
TOTAL: $1175
The Class 5 in stock form is a bit of a one trick pony, albeit a very good one. However, Lyle's True Plexi mods take it into an entirely different tonal territory. His take on power scaling lets you easily dial in "bedroom" volumes. Want to go to "11"? Just turn it all the way up and it's out of the circuit.
The switchable gain mods give you 3 different (low, high and normal) levels of gain for any given setting.
The 10" Celestion Greenback is a nice upgrade over the stock speaker. The Mercury Magnetics output transformer gives you all kinds of internal/external speaker options, as well as some really nice tone.
The cab is in excellent condition, with just a couple of small scuffs/snags on the lower rear area. Comes with stock tubes (Marshall branded JJ EL84 and (2) Marshall branded 12AX7A's.
SOLD shipped CONUS PayPal friends and family. Regular Paypal add 3%
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