Pre-amps into amp FX loop return ~ a question with a twist . . .

ChrisMusic

I am totally out of my depth with this one.

Recent discussions on here have got me thinking about trying different pre amp type pedals straight into the FX loop return.

There seems little point having good EQ on the pedal and then re-EQing it all again in the pre-amp, that is part of the rational anyway.

The AMT range look really interesting and according to @monquixote & @digitalscream sound pretty good too.  The YT demos certainly sound very credible.

The Bogner Red seems like a good bet too, but not line level and not good straight into power amp, so probably designed to take into account pre-amp gain and contouring I guess and that will be a big variable in how it sounds.

Now for the twist in my question, whilst longer term something like the EVH may well beckon (the germ of this idea was born in Drew's EVH thread), I currently have a DT25.

I have no idea about the architecture of the DT25, especially with the amp switching.  I assume that it is switching both pre-amp and power amp characteristics.

So by going straight into the power amp section via the loop return, does anyone have a good guess as to what I might expect to happen when switching?  I do like the idea of class switching etc, but I'm not sure what will happen in practice.

Is this a good or a bad idea?  Have I missed any other options?

How much influence does the power amp have over final tone?

(Ideas around Kemper and AxeFX are starting to haunt me too...)

I also want to run all this in stereo with another DT25, so I am guessing there is a minefield of potential ground loop issues too, and I don't know what level the FX loop operates at, but I am guessing it will be line level.

digitalscream

To be honest, you're probably in the best position to determine what the power amp's effect on tone is given that your amp can switch classes. If you were using an AMT pedal, it should be absolutely fine; the only thing I'd say is that you should keep the pedal's output volume all the way off before powering up...if your amp has the master volume before the loop, you're effectively running it at full volume

monquixote

I don't know much about the DT25 I'm not sure what it will do, but I suspect you will be able to use the preamp out of the AMTs into the loop without much bother. 

I'm not sure a DT25 would really be my ideal choice for solid state modelling pedals TBH. I'd probably go with a simple valve or solid state amp with a good clean channel.

If you are playing about with these sorts of pedals don't overlook the Tech21 Character pedals. 

dunstanmus

I realise you want to utilise your amp. Have a look at the Two Notes CAB. You can do what you are looking to do but go straight into computer or PA and it sounds awesome. Deffo works well with Bogner Red.

Cheers Rich

ChrisMusic

Cheers for that guys.

The DT25 is my current amp, so I am hoping that the configuration switching will give me extended sonic flexibility, depending how it has been implemented. (these things are seldom as simple as they seem)

The question about power amp influence on final tone is more about keeping one eye on the future, and whether SS or valve output sections will have a major difference, and whether FRFR may be the way to go with AxeFX / Kemper or keep it more traditional as @Drew_fx has been thinking recently.

The EVH and the AMT Stonehead are very different beasts, but are on my radar, and obviously represent each technology.

And FRFR is going to be a minefield too, I cannot imagine that is without the influence of amp and speaker coloration adding to the variables.  Interesting journey, this.

I have not been back into playing again for long enough to get a handle on current amp technology etc, and in the past I was never really happy with what I had, so it is all a bit of a wonderful experiment at the moment, along with a little guidance from you guys. 

Cheers,

Chris

ChrisMusic

@dunstanmus - thanks for that Rich, I'll check it out, always good to get feedback from someone who has tested things out in performance - cheers, Chris

ICBM

Just try it. Run anything - any overdrive or distortion pedal you have, or just the guitar if you don't (although a clean signal will show up changes less) - into the FX return, and operate the switching on the amp.

My guess as to what will happen… nothing, unless you use the physical switches on the amp. All the rest will probably be done in the digital domain. So if you want to run two amps, just set them the same.

ChrisMusic

Thanks ICBM.  The physical switches on the DT25 are only 'soft switches' anyway.  Do you know how I would find more info about this amp and how it works, the L6 site is woefully lacking.  Even basic info on its architecture would help (as long as I can understand it that is).  I thought when I bought it it was a valve amp with digital switching, I'm not sure about the modelling aspect of it.  I got it when I first started back playing again, so maybe a bit of a newbie moment, seems like quite a nice amp though.

It would be nice running stereo power sections, to use the two pre amps as a 4 channel, but I guess any power amp configuration would be switched at the same time as channel changes.  (It has channel switch jacks and midi too btw)

I take it from your reply that you think the class switching (etc) may be digital pre-amp stuff, or did you mean digitally switched power amp stuff?

ICBM

I assumed the switches were physical switches which changed things in the power amp. If they're soft switches, they could be operating relays or some other form of switching which is changing stuff in the power amp and then that could be controlled by the preamp too.

Just try it, it will be fairly obvious.

I'm pretty sure that it will be a digital modeller with a valve power section, even if in this case there may be more going on in the power amp - but there can't be a lot with only one 12AX7. They're not above misleading terminology about this sort of thing though, I remember there was something about the Spider Valve which implied the valves were part of the modelling, but really it's just a Pod with a valve power amp.

Drew_TNBD

Interesting thread. Makes me think though, what exactly are you trying to get here? Is the DT25 not giving you everything you want??

ChrisMusic

Found a great YT demo of the Two Notes Torpedo CAB Speaker Simulator, so I thought I would share it.

Pete Thorn does these things so well.

I didn't know about this, or the company, so thanks for pointing them out @dunstanmus

>link to Two Notes site<

edit: added a link to an Ultimate-Guitar review (which reads more like PR but lots of info too)

ChrisMusic

Thanks ICBM, I'll take some time with this and run the amp through it's paces.

The latest DT25 update makes it seem much more like it is a modelling front end from the facilities, although I've not done the update yet.  When I bought it I assumed from what I had read that it was digitally switched analogue signal path.  L6's website was very non committal, or I was just naive, and I seemed to know more about the amp than the guy I bought it off.

I did have my suspicions about the modelling thing, but it is basically just vol, gain, EQ, master, plus reverb, two channels of normal style controls, presettable out of four basic amp types.

That along with the architecture switching; pentode / triode and class A / AB, and Bogner design, which is what drew me to this in the first place.

It does sound pretty good to my ear, which admittedly after years away from the whole music biz thing they need re-educating and re-nuancing (if there is such a phrase).  The presumed abilities to independently (?) switch the power amp architecture should make this a good base for starting these experiments, and hey, I own it already, so zero extra hassle and cost for now on that score.

So in answer to your question @Drew_fx, you know the score, there is always another sound, another approach, another avenue to explore.  This is all part of the wonderful journey of expressing the ever-changing sonic landscapes trapped inside our minds.

I have one eye on the future too, so whilst the DT25 is fine for now, it has limitations, and there are other solutions beckoning on the horizon.  Anyway I have no idea what direction this chapter in my life will take me, so a good working knowledge of the technological solutions will leave me much better armed when, and if, opportunities present themselves.  And hey, I am just enjoying the ride, and the journey, so why not.

ChrisMusic

Just thought I would ask if the logic is there for what I am asking ?

It seems maybe a little unconventional but reasonable to me.  Especially in looking beyond the DT25 to the future.

But I feel like a bit of a newbie all over again, so what do you guys think?