How would you improve this rehearsal setup? (Axe-Fx 3)

Last night was my first practice with a brand-new AXE-FX III. I recently sold my Kemper in favor of the AXE-FX III because it can run multiple guitars at once, allowing me to route our second guitarist into my rig and…hopefully…get a nice tight and crisp sound by offering me a ton of control over our tone.

We play high-gain stuff, 7-string and 8-string guitars, and very loud - so it's naturally a very challenging environment. My hope that we could find a better, more cohesive sound with digital modeling than we could otherwise with real amps now that we are both direct. Better noise gates, EQ, multi-band compression, etc.

It sounded okay - we managed, but far from what I'd like to hear.

To keep it short and to the point:
  • Sound was okay at low volumes, but once the drums kicked in (and our drummer is LOUD) things got mushy. A lot more sound was in the room and it just got hard to discern what was what. Keep in mind we don’t even have a bass player right now. I know this is pretty common issue people run into - where's the best place to start tweaking though? In what order would you do things?
  • Rig rundown: AXE FX III -> Matrix GT800FX in stereo mode (400W each channel) going to two 16-ohm 4x12 cabs. I cut <150hz on the CAB blocks to try get rid of the mud in the PAs. I attached a diagram to help clarify.
  • I ran the CAB sims out to FOH (output 1 L/R), while just the AMPs in SSPA + Cab mode (output 3 L/R) out to the Matrix GT800FX and real 4x12 cabs. To clarify, I am not running two guitars through one amp block in stereo. Instead I used a mixer block to combine two separate signal chains, before sending to an output panned hard left/right.
  • If we play with IEMs, we sound incredible. I love playing with IEMs but it takes a lot of setup, and for small gigs it’d be nice not having to rely on them. I really like to dial in a good FOH sound first. The IEMs are a nice "this is what we COULD sound like" reference point however.
My gut instinct is that the GT800FX isn’t powerful enough for two guitar cabs at the volume we need - and having to rely on both the PA system and the two cabs, is simply too many sound sources fighting in the small room. The PA alone lacks a lot of tone the 4x12s offer (sounds tinny, lacks the oomph), but the two cabs aren’t loud enough to surpass the drums. Is this a reasonable conclusion? Or is there something else I could be doing wrong? Perhaps a better way to setup the room? I really don’t want to sell the GT800FX, and I don’t think the GT1000FX would make a big difference in this scenario. Perhaps the GT1600FX would work, but then I’d need a new rack and that's just even more gear and money I don't want to spend. We rent the practice space - so the PA system, mixer, and cabs are not ours.

Ideas? I’ve attached a diagram of how the practice space looked last night. How might you have done things differently if this is what you had to work with?
 

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Reduce bass so it’s not mucking up the mix.

Consider trying neither real amp/cab or full range, maybe not both at the very beginning. It’s hard to balance those 2 especially if you’re not familiar.
 
Yeah I definitely plan on sweeping the bass at volume next time to try and set that better. I'd prefer to use just the cabs exclusively as you suggested, but I think my GT800FX isn't powerful enough - unless I'm doing things wrong. I turn it up until the little red peak light hardly lights up, if at all.

I'd also like to add that when using both amp/cab & PA together, it felt like there was a very subtle delay between the cab and the PA systems response. The cab responded quicker than the PA. This make sense of course - there are fewer blocks in the AX3 signal chain for the cab output and perhaps that helps lower the latency I assume - among a variety of other reasons that could cause this. Perhaps I could add a very small delay to compensate for the PA on the cab side, is there a way to do that on the AXE-FX? Something like the sample-delay block in Logic Pro.

(also I attached a diagram of my AXE-EDIT to the original post)
 
Yeah I definitely plan on sweeping the bass at volume next time to try and set that better. I'd prefer to use just the cabs exclusively as you suggested, but I think my GT800FX isn't powerful enough - unless I'm doing things wrong. I turn it up until the little red peak light hardly lights up, if at all.

I'd also like to add that when using both amp/cab & PA together, it felt like there was a very subtle delay between the cab and the PA systems response. The cab responded quicker than the PA. This make sense of course - there are fewer blocks in the AX3 signal chain for the cab output and perhaps that helps lower the latency I assume - among a variety of other reasons that could cause this. Perhaps I could add a very small delay to compensate for the PA on the cab side, is there a way to do that on the AXE-FX? Something like the sample-delay block in Logic Pro.

(also I attached a diagram of my AXE-EDIT to the original post)
Blocks don’t add perceptible latency really. If you were closer to your cab, simply being farther from the P.A. would do this.
 
You're probably right. I was standing with the PA behind me, and the cab about 8ft in front of me. Kind of the reverse of your typical show format where the stage monitor is in front of you, and the amp/cab behind you. Why does that setup work well for so many venues and performances? Larger room? Amp/cab not actually all that loud since it's being mic'd?
 
Your instinct is probably correct. The Matrix GT800FX is only 120 WRMS per side into 16-ohm loads. That does not give you near enough headroom to handle musical peaks.

To get where you need to be, look for something that's 300 to 500 WRMS into a 16-ohm load (per side).
 
Your instinct is probably correct. The Matrix GT800FX is only 120 WRMS per side into 16-ohm loads. That does not give you near enough headroom to handle musical peaks.

To get where you need to be, look for something that's 300 to 500 WRMS into a 16-ohm load (per side).
Thanks for your reply. Up until now I felt unsure if it was just me, or it simply was not powerful enough.

I think what I may do next time is use the GT800FX in bridged mode for just one cab (520W in 16-ohm), then use the Marshal head already in room to drive the second cab, with the AXE-FX as just an effects processor for it. I'll try and report back if that cleans things up.
 
What does the amp put into 4ohm?
Would you consider rewiring the cab to 4 ohm?

Or even running just 2 speakers in each cab to get 8ohm?

Or... Crazy I know.. can you get the drummer to play softer?
 
I don't know enough about the amps so will steer clear of that bit.

But I would emphasise the frequency separation angle - if you ever get to hear solo'd tracks from your favourite guitar album you'll likely be shocked at what it sounds like, very little bass etc.

So look at your frequencies, make sure you're leaving the kick drum and hi-hats room to exist, try not to clash with the snare.

Also avoid having both guitars taking the same frequency bands - if you've not thought of that.

Final point - adrenalin

Eh?

Maybe when the drums kick in, you're both digging in harder - you say the drummer is loud, that's a provocative thing gets the juices flowing.

So you did in harder to the strings.

But because of the noise, you can't hear yourself and you play harder still.

The other guitarist is doing the same.

etc.etc.

You mention in ears you don't have this so much, I think that in-ears take some of that excitement away.

Also remember the more distortion you have in your sound - that tends to boost low end, so as you're hitting the strings harder you're generating more gain and more low end.

Final, final point -

Compression - related to the above, loud, live drums are dynamic things - if you already maybe have borderline too much compression, the comparison to live drums will emphasise that, plus as you dig in (as above) your strings will compress more, your amp model will compress more - you lose more and more dynamics.

Try moving through your chain, remove as much compression as you can - maybe lower master volume levels on amps, try bypassing the multi-band compression you talk about etc. see if that makes a difference, digital makes it very, very each to produce impressive sounds with compression that get lost in a mix.

Hope something above helps
 
Thank you all for your responses. We did a rehearsal last night with the cabs alone, one being driven with my Matrix, the other being driven by a JCM2000 head w/ the AXE controlling it's SEND/RETURN loop. It was a big improvement over last time.

But I would emphasise the frequency separation angle - if you ever get to hear solo'd tracks from your favourite guitar album you'll likely be shocked at what it sounds like, very little bass etc.
Absolutely. I took it a step further yesterday and cut way more bass than I normally do in my studio mixes. Hard into the 200's and 300's this time, this helped a lot with getting that crisp - high attack sound we were after. It felt wrong cutting out those frequencies at first, but I guess that's pretty normal for live stuff? I usually roll off around ~120 in my studio mixes.

Your instinct is probably correct. The Matrix GT800FX is only 120 WRMS per side into 16-ohm loads. That does not give you near enough headroom to handle musical peaks.

To get where you need to be, look for something that's 300 to 500 WRMS into a 16-ohm load (per side).
I'm starting to doubt this now. From my understanding, the other amp in the room (a 100W JCM2000 tube head) was overpowering my Matrix 800 in bridged mode (max of 520W). The master knob on the tube amp was only at 5. I'm very skeptical that I was delivering close to 500W RMS to the cab and still being over powered by a 100W JCM2000 head. Other sources say that amount of power would be painful. The cab's themselves (Marshall 1960A) are also only rated to 300W in mono mode (16-ohm). 🤔

I think I found the real problem:
I reached out to Matrix, and did a lot of digging around this forum and I believe I've been using the GT800FX incorrectly. I had the output on the AXE-FX set to -10dBu, instead of +4dBu. The GT800FX should give me a max of 120W per side in stereo mode into 16-ohm cabs. 20W more than what the JCM2000 can deliver, and that's plenty loud on it's own. I figured I was clipping the input to my matrix when I saw the signal LEDs go from solid green to red, but from my understanding it's pretty hard to clip the input stage of the Matrix - if that's even possible. I think both the red and green are coupled to the output stage, so I was indeed maxing out the amp but sending it a really quiet signal. It all seems obvious to me now - I read the user manual a handful of times but it only just clicked for me.

Anyway, hope to try this setup again next Monday, but have both cabs driven by the Matrix in stereo mode - allowing for me to have more precise control over the sound of the second guitar.
 
and our drummer is LOUD

Tell him (or her, been there as well) that dynamics is not just for p**sies. That drumming with precision and control is infinitely better then just banging those drums like a caveman. Or cavegirl.

Loud drummers are annoying because they force everybody to turn their volumes up, causing volume wars. And volume wars are one of the biggest reasons why bands have bitter breakups. I experienced one myself for that very reason. At least the asshole guitarist with his full Marshall stack that absofraggin'lutely has to be turned up full for the proper sound has become a dying breed. The caveman drummer on the other hand has proven to be a far more virulent hard to kill strain.
 
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