My son has a technical effects loop question I can't answer

Chad Beattie

Experienced
I'm getting older and lazier and just going with the "if it sounds good, then go with it" mantra...

But my much smarter and curious son who has been playing with the Axe-Fx III asked me if using a real amp with an effects loop how would you mimic that in the Axe-Fx. I honestly have no clue. He was saying something about the effects loop sitting between "preamp and power amp".

I did say that often in the physical world the reason they do things a certain way is because that is the only option. And thus if it sounds good then that is what to focus on in the Axe-Fx :) But figured someone would have an answer if I asked on the forums.

Thanks
 
An amp effects loop is the compromise. It was designed to let you put effects “after the amp” like you could in a studio, but clearly it’s not after the cab. So I personally am not trying to chase that sound.

On the axe you can’t insert something before the power amp so I believe there’s no way to do it. However since the amp effects loop is the compromise, I’d rather have the intended thing which is effects after the mic on the cab which we can do easily.
 
You can't do that specific thing, as noted above. But keep in mind that you can put a stomp box between the amp and cab, or even after the cab, which you can't do in the "real amp" world. Well, at least apart from micing the cab and running through outboard effects/PA, that is. In actual use, putting the effect in different places in the signal chain alters what the effect actually processes. For practical purposes, moving the blocks in the Axe FX grid accomplishes the same thing, tonally, and works as well. It could be argued otherwise, but I haven't found any advantage to the actual effects loop in my amps. On the contrary, the Axe FX is easier to use effectively (no pun intended) and you can do things you simply couldn't do otherwise.
 
I struggled with this when I first got my AxeFx. In the real tube amp world, my lead tone was my rhythm tone with a chorus (very slow and wide) and DLA pedal in the effects loop pushing the power tubes (I simply engaged the effects loop for my leads, and disengaged it for rhythms). This gave me the boost, saturation, smoothness, and HF roll-off I wanted for the leads. I struggled really hard to get that sound with the Fractal stuff, and couldn't... at least not the way I was used to doing it. But with 4 amp channels per preset, I was able to dial in a similar lead response relative to my rhythm tone. It is possible to emulate, but you have to be creative in how you get there.
 
They don't use the effects loop that often it in the studio. In the studio they usually record the track dry and add delay und reverb and whatever afterwards. And they often turn the master way up and drive the poweramp way into distortion. So....
 
T
Interestingly, there’s no easy way to do exactly what the Axe-Fx is doing using real gear either.
This! (Except there is, kind of...)

Back in the day, a lot of people wanted to duplicate with their live amp what was being done in the recording studio, which was to put studio quality time-based and modulation effects on a guitar, and to have them within their own control rather than that of a front of house engineer. The problems with running any of these effects between the guitar and the amp were twofold. It meant the effects sound was massively distorted and compressed by high gain preamps, and the levels and impedance were all wrong for most of the nicest rack gear, as low impedance line level studio effects units didn't often play nicely with high impedance instrument level signals. Not sure what the first commercial guitar amp with a line level effects loop was, definitely out of my price bracket at the time, but it worked and lots of people wanted it.

When I finally got myself into a position to try and do this properly I ended up with a Marshall JMP-1 feeding a 50 watt per channel Marshall stereo tube power amp into 2 JCM800 4x12s, a Boss ME-5 to provide "up front" stomp effects and midi control for channel switching (to me this seemed mind blowingly state-of-the-art for the mid-90s), and I got as far as borrowing a Yamaha SPX90 before realising I didn't particularly like the guitar sounds I was getting, so aborted on an expensive project. Within a couple of months I was back out of debt, and using an old Marshall JMP Mk II 50 watt head into a Simms-Watts 4x12, some stomp boxes (inc. first TS-10, yay!) and a WEM Copicat, all up front of the amp.

It took me a while to get my head around the Fractal way of doing things, but it's doing the near impossible. It mimics what was being done in the studio in the 80s without the compromise of any power amp distortion colouring or compressing those time based effects. The way to do exactly what the Axe FX is doing with real gear would be to take stomp boxes, a real amp and cab, a quality microphone or 2, an isolation chamber for the amp, a studio desk with some nice outboard rack units, and a good FRFR cab for monitoring out to the rehearsal room or gig.

To me, the power of the Axe FX is completely mind blowing. I am guessing that some of the things Fractal doesn't achieve as perfect imitations of real life are because the real life examples are massively compromised. There are times when I want a chorus or delay to sound like it has been completely brutalised by preamp distortion, and there are others where I want it to sound like a studio effect that has been laid on after. History sent us through a period where the best we could do was to insert the effects we want to sound "natural" somewhere in the middle of all that mess, but I think we have only done it because it's the best we can achieve. Fractal achieves the two things I really need, pretty much perfectly. Bitterest pill was that Fender spring reverb sounds work perfectly after the cab block. Who'd have thunk it? I'm so used to them being between the preamp and the power amp.

Now I know mileage of many other will vary, and I write all this with no disrespect to 4CM users. I know many achieve great results and tones with something that feels right and works for them (and the Axe FX is well set up to be part of such a rig). We all have to do what works for us.

Short answer for your son: Effects loops are a compromise that we accepted because the power amp colours the "effected" signal so much less than the preamp. Laying the effects on after the cab isn't possible in a conventional amp setup (without taking a recording studio on the road with you), but it is in the Axe FX, and for many of us that is a much, much better way of doing things.

Liam
 
So....dumb idea here...

The Axe FX III has multiple amp blocks, right? I know you can disable power amp modeling. Can you also disable the preamp? If you can, it's simple:

... > Amp 1 (power amp off) > effects loop blocks > Amp 2 (preamp off) > ...

If you can't disable the preamp emulation, then you could replace Amp 2 with a neutral-sounding amp model and set the preamp flat and clean. That would be a serious compromise, but....so is an amp's effects loop.

Alternatively, you just leave power amp modeling off and don't worry about it.

Most of the time when people use effects loops, they're getting all the "tone" from the preamp and the power amp is run clean just to make it louder. I don't like running amps like that. Heck, hating even well-regarded master volumes but wanting to play quieter is a large part of why I tried out modeling in the first place. But, if you're comparing Fractal to an amp with a loop and the master on 1...you get that by turning the power amp off in the Fractal.

I can't think of a reason why you'd actually want to do this as opposed to just putting the "loop" effects after the amp block. But, that's how you do it.
 
Yeah, unfortunately, you can't recreate that in the Axe III. I wish you could. Many see them as signal compromise, but I found the simple loop on my Matchless to be quite useful. Wish I had that option with the Axe, but I'm still very happy running my pedalboard in front.

It would be amazing, though, if we could get the authentic FX loop for the amp, and an "ideal" tube buffered FX loop option.
 
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I'd like to bottom line this topic, which has been discussed quite a bit in this forum:

If you can't get a sound you are happy with from an Axe Fx III, there's something wrong with your ears. ie, there's no need to do things exactly like the way an amp and pedals do it: Fractal does it better (from a sound standpoint)...and it's 10,000 times easier!

My 2.5 cents.
 
I'd like to bottom line this topic, which has been discussed quite a bit in this forum:

If you can't get a sound you are happy with from an Axe Fx III, there's something wrong with your ears. ie, there's no need to do things exactly like the way an amp and pedals do it: Fractal does it better (from a sound standpoint)...and it's 10,000 times easier!

My 2.5 cents.
Bottom line this topic? Are they about to lock this thread? o_O
It's not possible on Axe FxIII. Maybe in the next generation unit the preamp could be encrypted not to expose the inner workings of it?
 
I don't think a loop is desirable at all?
To me a loop is not more than a weak compromise at best. They had no better way to do it. But why should you want one in a perfect digital world?

The idea was to put everything in the loop that should not get distorted, like delays and reverbs, but even that part of the plan failed when you cranked the poweramp. So your reverb was more or less distorted, depending on how loud you needed your amp. You want that?

You could also ask for shunt blocks that steal some highs and crackle at times, so you could emulate the typical stuffed up 90'ies guitar rack.

But why? My sound is way better now than it has been back then, why should I look back?
 
Bottom line this topic? Are they about to lock this thread? o_O
It's not possible on Axe FxIII. Maybe in the next generation unit the preamp could be encrypted not to expose the inner workings of it?
So, the reason why I gave my bottom line opinion is because it's a somewhat irrelevant topic. Fractal does it better...why would they go backwards and do it like amp/pedals do it? As many have said, the amp way is a work around and not as good for sound quality. It was invented due to limitations.
 
So, the reason why I gave my bottom line opinion is because it's a somewhat irrelevant topic. Fractal does it better...why would they go backwards and do it like amp/pedals do it? As many have said, the amp way is a work around and not as good for sound quality. It was invented due to limitations.
Some of the best art (music, movies, etc) comes from people trying to work around something that is not ideal. One person's compromise is another person's ideal.
 
I'd like to bottom line this topic, which has been discussed quite a bit in this forum:

If you can't get a sound you are happy with from an Axe Fx III, there's something wrong with your ears. ie, there's no need to do things exactly like the way an amp and pedals do it: Fractal does it better (from a sound standpoint)...and it's 10,000 times easier!

My 2.5 cents.
I disagree. The Fractal stuff is meant to be the closest digital recreation of the real amps it models, correct? Aren't we always talking about accuracy? I mean, Cliff changes the bias excursion in an amp due to new measurements or measurement techniques... seems accuracy is the #1 goal.

Are amp FX loops critical? No. Are they well designed? Mostly no, but some have little to no negative effect on tone (tube buffered FX loops for example).

I ran wet effects through the loop of my DC30 for a long time and liked the way they affected the power section of the amp. That's a distinct sound vs running the effects in front of the preamp or after the amp and before the cab (which you can't do with a real amp). Having the ability too recreate the FX loop sitting between the preamp and power amp is really a matter of accuracy than anything else, but it would be nice to be able to recreate that aspect of the real amp too.

Just my $.02
 
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The idea was to put everything in the loop that should not get distorted, like delays and reverbs, but even that part of the plan failed when you cranked the poweramp. So your reverb was more or less distorted, depending on how loud you needed your amp. You want that?
Yes! In some circumstances. It's a distinct sound when the power amp of a DC30 is breaking up with delay and reverb in the FX loop.

When did you ever run effects after your cab live? Never. Is it better or worse? Depends. I don't like the sound of effects after the amp/cab, some do. The fact that you can't recreate that setup live with a real amp (without effects at FOH) makes it a no-go for me... just doesn't sound right as a live rig... too sterile and clinical.
 
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