Main trade-off
NUX MG-30
Its included external switch occupies EXP1, so that same socket cannot also take a second expression pedal.
Head-to-head
NUX MG-30 vs NUX MG-400: Does your amp need the effects loop?
The short answer
Choose MG-30 if the rehearsal amp has an effects loop and you need its own preamp between your drive and delay effects. MG-400 cannot split its chain that way because it has no Send/Return. Choose MG-400 when the whole chain goes to headphones, a full-range speaker or one amp input and two onboard CTRL switches are enough. Its manual already documents Dry Out and Reamp, so recording an untreated take for later processing does not by itself require the MG-30. The MG-30 external switch is included, but adds a cable and uses the socket otherwise available for a second expression pedal.
Before you choose
The reasoning and the trade-offs
The rehearsal amp can make the loop essential
Suppose home practice uses headphones, but rehearsal uses an amp whose preamp you want to keep. If drive effects belong before that preamp and delay belongs after it, MG-30 can put the amp inside its movable Send/Return path through four cables. MG-400 has no loop, so its own chain cannot straddle that preamp. Choose MG-30 for this actual wiring requirement. If rehearsal uses a full-range speaker, or the whole processor goes into an amp return with the amp preamp bypassed, the split is unnecessary and MG-400 can cover the simpler connection.
What this is based on
Headphone practice plus reuse of a specific amp preamp crossed with effect placement. MG-30 manual printed pages 5 and 9-10 and current four-cable documentation, compared with the complete MG-400 panel inventory on printed pages 3-5. The amplifier must itself have Send/Return.
Main trade-off
NUX MG-400
There is no Send/Return pair for placing the amp preamp inside its effect chain.
Original MG-30 shown. The included NMP-2 LITE dual switch and its cable are not pictured.
NUX MG-30
- Choose it for
- Keep the amp preamp in a four-cable setup and place effects on either side of it.
- Use the included NMP-2 LITE for extra control, accepting its cable and the shared EXP1 socket.
- Main trade-off
- Its included external switch occupies EXP1, so that same socket cannot also take a second expression pedal.
Manufacturer photo shows orange footswitch caps. Their inclusion in the selected Amazon package is unverified.
NUX MG-400
- Choose it for
- Pack away one unit with built-in expression and two onboard CTRL switches.
- Use the documented Dry Out and Reamp workflow when computer recording is the main job.
- Main trade-off
- There is no Send/Return pair for placing the amp preamp inside its effect chain.
About this comparison
NUX MG-30 vs MG-400 for home recording and amp rehearsals. Compare four-cable routing, onboard controls and the USB jobs MG-400 already covers.
This is an editorial upgrade comparison for a guitarist buying one processor for headphones, a computer and an existing rehearsal amp. The shared job is credible without an asserted price gap. The decision is whether the amp needs split effect placement or the smaller all-in-one control layout already covers the routine.
Winner by situation
Start with what you need it to do
Keep a loop-equipped amp preamp between drive and delay
MG-30 supplies the processor Send/Return needed for that four-cable arrangement. MG-400 cannot split its own chain around the preamp.
- NUX MG-30
- Better fit
- NUX MG-400
- Not suitable
Pack away daily with two onboard CTRL assignments and expression
MG-400 keeps both CTRL switches and expression on the main unit. MG-30 uses its included external switch to extend onboard control.
- NUX MG-30
- Good
- NUX MG-400
- Better fit
Computer recording is the main reason to buy
Both have USB audio. MG-400 also documents Dry Out and Reamp, so that workflow alone does not justify the MG-30 upgrade.
- NUX MG-30
- Good
- NUX MG-400
- Good
Use the included MG-30 switch and a second expression pedal on EXP1 together
MG-30 EXP1 accepts either accessory. MG-400 has no corresponding external expression connection.
- NUX MG-30
- Not suitable
- NUX MG-400
- Not suitable
What matters in practice
The differences that matter
The rehearsal amp can make the loop essential
Suppose home practice uses headphones, but rehearsal uses an amp whose preamp you want to keep. If drive effects belong before that preamp and delay belongs after it, MG-30 can put the amp inside its movable Send/Return path through four cables. MG-400 has no loop, so its own chain cannot straddle that preamp. Choose MG-30 for this actual wiring requirement. If rehearsal uses a full-range speaker, or the whole processor goes into an amp return with the amp preamp bypassed, the split is unnecessary and MG-400 can cover the simpler connection.
How we reached this conclusion
Headphone practice plus reuse of a specific amp preamp crossed with effect placement. MG-30 manual printed pages 5 and 9-10 and current four-cable documentation, compared with the complete MG-400 panel inventory on printed pages 3-5. The amplifier must itself have Send/Return.
An included switch still has to be packed and connected
When the practice space becomes a family walkway again each evening, a separate switch is another item to reconnect. MG-400 places its two assignable CTRL switches beside up/down and the built-in expression pedal. MG-30 includes NMP-2 LITE, but its lead occupies EXP1. Choose MG-400 if two direct control assignments cover the songs and keeping the floor setup together matters. MG-30 becomes more useful when its extra control arrangement or an additional expression pedal is needed, provided you accept that the external switch and that pedal cannot share EXP1 at once.
How we reached this conclusion
Repeated pack-away and two immediate effect actions crossed with the physical controls and exact included accessories. MG-30 printed pages 7, 10 and 14, MG-400 printed pages 3 and 9-10. This is a setup comparison, not a claim that one switch layout is easier for every player.
A dry take does not make MG-30 a necessary recording upgrade
A guitarist who can record only while the room is free may want to play the part once and adjust its processing later. MG-400 explicitly offers Dry Out and Reamp, so that workflow does not require buying MG-30 or keeping a separate guitar interface solely for this job. Choose the unit around the amp connections and foot controls you actually need. MG-30 still makes sense when its loop solves rehearsal wiring, but a USB label alone is weak justification for the upgrade. Verify the computer, driver and DAW routing, and do not assume either mode name promises simultaneous processed and untreated tracks.
How we reached this conclusion
A limited recording window plus later tone decisions crossed with MG-400 printed pages 11-12 and MG-30 printed page 12. The conclusion uses the affirmative MG-400 routing diagram, without assigning undocumented channel counts to either unit.
Choice A
Original MG-30 shown. The included NMP-2 LITE dual switch and its cable are not pictured.
NUX, MG-30
NUX MG-30
Keep the amp preamp in a four-cable setup and place effects on either side of it.
- Best matched use
- Keep the amp preamp in a four-cable setup and place effects on either side of it.
Checked facts
- Keep the amp preamp between effects: Movable Send/Return and documented four-cable connection.
- Controls that stay on the main unit: Three onboard switches. NMP-2 LITE dual switch and cable included.
- Expression and future control changes: Built-in expression. EXP1 accepts an extra expression pedal or NMP-2 LITE.
- Record now and choose processing later: USB audio with separate recording and playback levels.
Choice B
Manufacturer photo shows orange footswitch caps. Their inclusion in the selected Amazon package is unverified.
NUX, MG-400
NUX MG-400
Pack away one unit with built-in expression and two onboard CTRL switches.
- Best matched use
- Pack away one unit with built-in expression and two onboard CTRL switches.
Checked facts
- Keep the amp preamp between effects: Complete connection inventory has no Send/Return sockets.
- Controls that stay on the main unit: Up/down plus two assignable CTRL switches onboard.
- Expression and future control changes: Built-in expression, with no external expression socket in the panel inventory.
- Record now and choose processing later: Normal, Dry Out and Reamp are documented, including the editor routing diagram.
Meaningful differences
What changes the fit
| What changes | NUX MG-30 | NUX MG-400 | Why it matters |
|---|---|---|---|
| Keep the amp preamp between effects | Movable Send/Return and documented four-cable connection. | Complete connection inventory has no Send/Return sockets. | MG-30 can divide its effects around a compatible amp preamp. MG-400 sends its complete chain to the chosen destination. |
| Controls that stay on the main unit | Three onboard switches. NMP-2 LITE dual switch and cable included. | Up/down plus two assignable CTRL switches onboard. | Count the separate switch and its lead when the setup is cleared from the floor after practice. |
| Expression and future control changes | Built-in expression. EXP1 accepts an extra expression pedal or NMP-2 LITE. | Built-in expression, with no external expression socket in the panel inventory. | MG-30 has an expansion choice, but the two external accessories compete for one connection. |
| Record now and choose processing later | USB audio with separate recording and playback levels. | Normal, Dry Out and Reamp are documented, including the editor routing diagram. | MG-400 already provides a dry-recording and later-processing route. Mode names do not establish simultaneous wet and dry tracks. |
What you give up
Every choice has a cost
If you choose NUX MG-30
- Four-cable use needs an amp with a loop, the additional cables and deliberate amp/cab settings.
If you choose NUX MG-400
- A later need for effects on both sides of the amp preamp means changing the rig or adding separate pedals.
Recommendation switch
The decision flips if...
The real amp preamp must remain between two parts of the processor chain
Choose NUX MG-30. MG-30 provides movable Send/Return for four-cable use, subject to a compatible amp loop and correct block settings.
One destination takes the whole chain and two onboard CTRL switches cover the songs
Choose NUX MG-400. MG-400 keeps those controls together and already supports dry recording and reamping.
What matters in practice
Before you choose
Keeping the real amp preamp between two groups of effects needs an effects loop in the processor. Recording over USB alone does not.
What this comparison cannot tell you
- This compares original MG-30, not MG-30 MKII. GEN2 firmware is not a hardware identity.
- No simultaneous wet-plus-dry recording-channel claim is made.
- USB audio does not replace the documented DC power requirement.
- No measured sound, latency or patch-gap advantage is claimed.
What the facts say
What the comparison shows
Useful conclusions from the current guitar multi-effects comparison, followed by the checked facts used to reach them.
See the checked facts and calculation notes
| Product | Needs matched | Checked facts | Source records |
|---|---|---|---|
| NUX MG-30 |
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| NUX MG-400 |
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Ready to choose?
Check the price. Read the owner reviews.
Open either model on Amazon to check the current price, customer reviews and delivery options.
Original MG-30 shown. The included NMP-2 LITE dual switch and its cable are not pictured.
NUX MG-30
Keep the amp preamp in a four-cable setup and place effects on either side of it.
Use the included NMP-2 LITE for extra control, accepting its cable and the shared EXP1 socket.
See price & reviews on AmazonManufacturer photo shows orange footswitch caps. Their inclusion in the selected Amazon package is unverified.
NUX MG-400
Pack away one unit with built-in expression and two onboard CTRL switches.
Use the documented Dry Out and Reamp workflow when computer recording is the main job.
See price & reviews on AmazonLinks open in a new tab.