4CM What's the advantage?

slinky005

slinky005

Power User
If your power amp has a serial and/or parallel loop, is there any reason to use the 4 cable method?
I am about to do my first show with the Axe going thru a cab and trying to find the best method.
Using a JVM head into my 1936 cab -want to only use the power amp section of the amp.
 
4CM method would not be used for this set up. It is only an advantage if you are using the whole JVM head, not just the power amp.
 
4cm allows you to use effects in front of the amp an din the loop at the same time. I do this with my JVM head, it's a little hissy but besides that works very well.
the Effects sound top notch. If you wan to use the amp models just run an output from the Axe into the return of the loop.
 
Also to add - in 4 cable method you have the option of using your JVM's preamp or the Axe's amp models per preset.
 
Sounds crazy but I love the sound of the Axe into the serial return - cabs and amp modelling on.
I have tried at high and low volume and to my ears it's cookin'.
I've tried turning sag off (and cab off) and eq-ing but anything I end up with doesn't have the oomph that I get the unconventional way.
Goes against popular wisdom but what the heck.
 
I used to run the Axe through a Mesa 2:90 & real cabs when I first got it & thought it sounded better with the sag (per amp modeling) on. A lot of the feel & character of the amps sims is there. I didn't like it with cab sims on. Sounded way to dark & boomy to me. The beauty of the Axe is there are so many ways to use it so go with what ever works bets for you.
 
Trying to wrap my head around this method.
From what I understand this should allow me to use the amp with the Axe in a standard fx loop for the fx only.
As well I should be able to go direct from the Axe into the loop but bypass the preamp on my JVM therefore allowing me to use the amp blocks on the Axe.
Just to confirm - I am using my serial loop not my parallel correct?
And to switch between JVM preamp and Axe do I just bypass the Fxloop in the Axe?

I have followed the diagram below using my serial loop.

4CMethodd.jpg
 
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slinky005 said:
Sounds crazy but I love the sound of the Axe into the serial return - cabs and amp modelling on.
I have tried at high and low volume and to my ears it's cookin'.
I've tried turning sag off (and cab off) and eq-ing but anything I end up with doesn't have the oomph that I get the unconventional way.
Goes against popular wisdom but what the heck.
Click to expand...

I find that works with some, but not all,of my patches
 
use the parallel loop at 100%, you'll that your levels will be much easier to
balance. check out th eJVM forum there is a whole thread abut using 4CM over there.
from that post (JVM forum is private so you'd have to join to see this)

"Using the serial loop for 4CM is problematic in my experience. Talking in terms of 'instrument level' (-10dB) and the more powerful 'Line Level' (+4dB) ...

The JVM serial loop runs at line level so consider the hookup and levels

Cable 1: guitar --> AxeFX Input.
All at instrument level. No problem.

Cable 2: AxeFX Loop send --> JVM Input.
JVM input is at instrument level therefore Axe FX Loop must be set at -10dB.

Cable 3: JVM Serial Loop Send --> AxeFX Loop return
JVM Loop is sending at Line level but ... uh oh ...the AxeFX Loop is at -10dB and will be potentially overloaded

You could set the AxeFX Loop to Line level but now you will likely get distortion at the JVM input ... probably what you are hearing on clean green.(this is what I was dealing with)

If you can adjust the AxeFX Loop send and return levels independently you may be able to get things working but on other MultiFX units I have found that this increases noise.

Better solutions are:

1) Use the JVM Parallel loop at 100% Mix at Instrument level (-10dB). This is by far the easiest and works pretty well but the loop MUST be at 100% or you will experience comb filtering (phasey nastiness). There is also a level drop which you must correct using the AxeFX output to get things back up to normal volume.

2) use a transformer device to convert the +4dB Serial loop to -10dB. Money.

I would suggest that you go with option 1. Set everything on the AxeFx and JVM to use -10dB (Loops on both units and output on the AxeFX) and see how you get on."
 
Thx for all that kmanick.
Would the transformer device help balance the level difference between the Axe into the amp and the amp on it's own?
This is currently the reason I can't use this method - just not enough headroom.

Another question:
I don't need any effects before the JVM I only want to have the option of using the Axe amp OR the JVM amp with the Axe in the fx loop.
Is the 4CM still the only way to do this?
 
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Sorry can't help you out on those two questions, I use effects in front in my set up (wah, drives, whammy pedal voice box)
so I just set it up like it says to do in the manual. I don't use any amp sims at all.


slinky005 said:
Thx for all that kmanick.
Would the transformer device help balance the level difference between the Axe into the amp and the amp on it's own?
This is currently the reason I can't use this method - just not enough headroom.

Another question:
I don't need any effects before the JVM I only want to have the option of using the Axe amp OR the JVM amp with the Axe in the fx loop.
Is the 4CM still the only way to do this?
Click to expand...
 
slinky005 said:
Thx for all that kmanick.
Would the transformer device help balance the level difference between the Axe into the amp and the amp on it's own?
This is currently the reason I can't use this method - just not enough headroom.

Another question:
I don't need any effects before the JVM I only want to have the option of using the Axe amp OR the JVM amp with the Axe in the fx loop.
Is the 4CM still the only way to do this?
Click to expand...

I run a JVM in 4CM (with the Output 2 mod in the Axe) and the way to do it is to use the parallel send and serial return in the JVM. This avoids the clipping that the serial send would cause. This will bypass the Marshall's built in reverb but this isn't an issue given that you have the Axe's reverbs available.

4CM is the easiest way to achieve either JVM preamp with Axe post effects, or Axe preamp with Axe post effects. Even if you don't want the pre effects in front of the JVM, the way to select between the two preamps is all in your grid setup in the Axe....

So assuming you're not using any switchers to take the Axe in and out of the Marshall's signal path and fx loop, if you want the Marshall's preamp, make sure your guitar's signal goes to the FX Loop block in the grid, so that it will then go straight to Output 2 of the Axe and into the Marshall's front input in typical 4CM style. You can then use your Axe post effects as usual when the Marshall's send goes into Input 2 of the Axe where you can then add effects in the grid post FX loop block.

If you just want Axe preamp (or even power amp and cab simulations as you like to use above), simply make a row for your signal path in the grid that avoids the FX Loop block so that it goes to an Amp Block (and optional Cab block) and then to any post effects you want. This avoids In/Out 2 on the Axe so the sound goes straight to Output 1.

Create presets that each have one of the two grid layouts above and switch between presets to effectively switch between preamps.

Some points worth considering. If you are planning on switching between both Marshall and Axe preamps, i would suggest not using power amp and cab modelling simply to maintain an overall tonal consistency for the mix your guitar is placed in. You would be effectively running an amp into a cab into an amp into a cab which will end up sounding rather bass heavy and more prone to vanishing in a mix.

You might also find that a lot of the Axe preamp models need their presence and treble rolled back when playing through the Marshall's power section.
 
slinky005 said:
A lot of great info, thx man.
Click to expand...

No worries man..enjoy!

I actually run my 4CM with an RJM Effect Gizmo. This allows me switch the Axe in and out of the Marshall, and i have the Marshall's dry preamp send going into a line mixer so that it's mixed in parallel to the Axe's post effects. This means i can avoid all the analogue to digital conversion and back. However the Axe is incredibly transparent so you don't necessarily need a switcher.

Overall, 4CM gives you a huge advantage because you can use any combination of Marshall, Axe preamps and effects.

Also, are you using a later generation Axe II that already has the Output 2 mod built in? If not, you might get some hiss going into the front input of the Marshall.
 
So I have a mark I II I'm guessing I do not have the output 2 mod? what is that exactly? I'd like to kill as much of the hiss I get (which is not a lot BTW)
that I can.
 
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Luca9583 said:
No worries man..enjoy!

I actually run my 4CM with an RJM Effect Gizmo. This allows me switch the Axe in and out of the Marshall, and i have the Marshall's dry preamp send going into a line mixer so that it's mixed in parallel to the Axe's post effects. This means i can avoid all the analogue to digital conversion and back. However the Axe is incredibly transparent so you don't necessarily need a switcher.

Overall, 4CM gives you a huge advantage because you can use any combination of Marshall, Axe preamps and effects.

Also, are you using a later generation Axe II that already has the Output 2 mod built in? If not, you might get some hiss going into the front input of the Marshall.
Click to expand...

I have the Mark II. Does that have the mod?
 
I'm pretty sure the Mark IIs have the mod as standard so you should be good to go. In the earlier generation units, Output 2 was wideband, so when using 4CM with certain amplifiers (including the JVM) you would get a lot of hiss from that output into the amp's input. As a result, the mod is available for those earlier units to reduce the bandwidth.
 
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