I find the Plexi models all quite dark. Explanation inside. Any help?

R

Random Hero

Inspired
I bumped another thread but think this warrants its own.

So for the longest time I’ve been looking for the ideal “Plexi” tone from a modeller. I guess we all know the sound I’m referencing but I’ve posted examples of the exact type of thing I’m talking about at the bottom of this.

To preface this, and I’m saying this for context rather than any other reason, I play professionally and know my gear etc. I don’t think the issue is me, though I am more than happy to be corrected if there’s something I’m missing..! This definitely isn’t a dig as I love Fractal gear and I’m about to use my FM9 on a UK tour.

On to the point - I find the Plexis in the current firmware quite dark and congested sounding and I don’t get why.
Earlier this week I started a little voyage into this after hearing the demo of the Metropoulos MetroPlex II I posted below. To me there is a lot of all of those descriptive words we use for Plexis embodied in that clip. It’s bright, has “kerrang” and “clank” and has those snarly upper mids and so on. For whatever reason, the models in the Axe don’t quite do that to me?
So I made some comparison clips using two amps in the Fractal - 1959SLP and the 100W High - and two “amps” in the Quad Cortex - a DI capture of the Plexi channel of a Friedman Smallbox and the Neural Plexi 100 Bright amp model. Listen for yourselves but for whatever reason, I can’t get the Fractal models to sound as bright or present or sizzly or whatever, not without extra EQ whether by way of a block or the output EQ or whatever.

Don’t get me wrong, there’s a depth and richness to the Fractal tones that I can’t quite get from the other unit so this isn’t a dig at all but I’m confused why I can’t get these tones without serious extra EQing? The Neurals sound closer to me in this context, EQ wise, and that surprised me.

- All of the clips above were using the same IR so it can’t be that, though I’m aware some IRs are much brighter but considering those tones exist using that IR, it’s not the IR. I also feel like once you start using overly bright IRs, something else is lost. Depth, weight, thickness and fatness.

- I’ve switched speaker impedance curves and whilst I do think it makes a difference, it’s subtle at best. It’s not night and day.

- I set the EQs on all three models (can’t control the capture EQ) to exactly the same.

I’ve also found that even when I dime them, I’m not getting as much brightness or sizzle as I’d expect, certainly not close to George Metropoulos in that clip..!

What say we? What’s the deal?

My recordings;
Same DI guitar track. Order is Fractal 100W High, Friedman Capture, Fractal 1959SLP, Neural Plexi model.



Examples;





 
Sounds like a plexi to me. Even Joe Bonamassa has plexis modded with a mid boost to bring the mids more forward and "brighter"

Try using a PEQ and boost around 2k with a Q of around 1-1.5 and sweep around until you hear the mids coming more "forward".
 
A really good starting place on most Plexi's (not necessarily modern amps) is Gain at 6, Bass at 5-6, Middle at 8, and Treble at 6 and presence at 6. The Tone controls really don't do much drastically on a Plexi. If you really wanna get there, try the JMP-1 Bass shift OD1 or OD2 with that 4 band EQ - that can get you there to Plexi land quicker, with a LOT more EQ control.

Make sure the IR is not dark either.
 
From a cursory listen on a common playback source (read: iPad) the 4 examples sound pretty close to one another. Given the 2 YouTube videos use completely different guitars, signal paths and recording methods, it is senseless to compare. I have a metroplex here, and honestly dont get anything out of it I wont get with the AxeFXIII models. It has tubes, they glow, they smell nice, it is super sexy, but I cant remember the last time it was powered on.

I do think your 4 examples all use a lot of gain, maybe moreso than the amounts presented in the Metroplex II video. Try backing off on the gain, try a different IR (or several), DEFINITELY try a dyna cab. There is nothing in those videos you cant get with an AxeFXIII. Sorry I cant be more help.
 
I agree with the above
I think all 4 of the clips sound good
The NDSP are a bit thinner brighter, The Fractal fatter and thicker in the low mids
One thing I would try in the Fractal Plexi play with the bright cap values also turn up the high treble in the amp ideal page
 
Random Hero said:
Middle cranked. 10. Treble up high, 7 and above.
Gain at 7 in the above clips.
Click to expand...
There’s a couple tricks you can try. Try these one at a time.
Raise the Low Frequency Cut in the preamp tab. My VH preset uses a dimed SLP 1959 and I set low frequency cut to 350hz.
Raise the Negative Feedback up a bit.
Raise power tube bias from 60% to 70%.
With the bright switch on, lower the gain to 5-6. The model brightens up as you lower the gain. Raise the input trim to get the gain up to where you like it.
Get Leon Todd’s LTTVmix-7 IR. It’s a bright greenback IR. Leon is 2112 on the forum. His IR’s are available on his website and axe exchange.
 
1. Try turning the gain down, particularly for the tone in that first metropoulos clip.
2. Try turning Presence up.
3. What are your Speaker compression and distortion settings at? Lowering those might help.
4. I would also suggest experimenting with your guitar pickup height. Setting the pickups lower will yield a less compressed tone with more dynamics.
5. You’ll probably need a different IR to sound closer to those YouTube clips. Close mic’ing adds a certain girth to the notes, and pulling back the mic thins the notes in a way that is different from EQ. I would try to go for something where the mics have a little distance from the amp. Dynacabs are great for this. I personally like the ribbon mic as far back as I can put it.
6. I personally like messing with the negative feedback and transformer match parameters on a Plexi to make it feel tighter, more open, and less flat/compressed.
 
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If you want to thin it up, try reducing low end in the Input EQ that’s in the Amp block.
 
Thanks guys. I really don’t want this to come across is I’m digging out the product. I love the product. I’m totally open to trying things and seeing if there’s something I’ve missed.
I also see a lot of “you’re doing this wrong or that wrong” but my point is that with either the real amp or models from other companies, it appears easier to get closer to this right away without going “under the hood” as it were and that surprised me. Not that it’s an issue - just curious.
Searching the forum, I’m not the first to suggest a little darkness so I don’t think I’m completely nuts 😂
And also, if every video clip I’m posting has that thing, it can’t be that futile to compare it to a model without knowing the signal chain. Using various IRs with the Fractal models so far I haven’t got quite there, whereas say a Headfirst capture of a dimed out 1987X into the same IR as posted here does seem to get there. As I’ve said, there’s a richness to the Fractal that isn’t elsewhere but… yeah.

On to the replies…

RoshRoslin said:
Sounds like a plexi to me. Even Joe Bonamassa has plexis modded with a mid boost to bring the mids more forward and "brighter"

Try using a PEQ and boost around 2k with a Q of around 1-1.5 and sweep around until you hear the mids coming more "forward".
Click to expand...

Interesting, thanks. It does sound like a Plexi, albeit a dark one.

I will try the EQ for sure, but my point is that the models sound inherently darker vs other examples - in general.

dr bonkers said:
You need to crank the high end.

Also, if it's still dark, you are pairing the amps with the wrong cab IRs.
Click to expand...

Ok, but that makes it sound like user error. The same IR produces much closer to what I’m hearing otherwise with the capture and QC model - including with a real 50w I used to own - and the models have less of that sizzle and brightness inherently.

austinbuddy said:
A really good starting place on most Plexi's (not necessarily modern amps) is Gain at 6, Bass at 5-6, Middle at 8, and Treble at 6 and presence at 6. The Tone controls really don't do much drastically on a Plexi. If you really wanna get there, try the JMP-1 Bass shift OD1 or OD2 with that 4 band EQ - that can get you there to Plexi land quicker, with a LOT more EQ control.

Make sure the IR is not dark either.
Click to expand...

IR is the same across everything in the clip I posted and it isn’t dark on some of the examples.

The settings for the clips I posted were Treble Gain 7, Bass 3, Mids 10, Treble and Presence 7. Rolling the mids back a little does brighten it a tad but it’s subtle again. My point is that on a real dimed Plexi there is far more hair and sizzle.

Bruce Sokolovic said:
From a cursory listen on a common playback source (read: iPad) the 4 examples sound pretty close to one another. Given the 2 YouTube videos use completely different guitars, signal paths and recording methods, it is senseless to compare. I have a metroplex here, and honestly dont get anything out of it I wont get with the AxeFXIII models. It has tubes, they glow, they smell nice, it is super sexy, but I cant remember the last time it was powered on.

I do think your 4 examples all use a lot of gain, maybe moreso than the amounts presented in the Metroplex II video. Try backing off on the gain, try a different IR (or several), DEFINITELY try a dyna cab. There is nothing in those videos you cant get with an AxeFXIII. Sorry I cant be more help.
Click to expand...

Maybe my examples do have more gain, a tad, but the MetroPlex is dimed completely, and I’m using far more conservative settings. If I was to dime it out, the increased input gain would only smooth it and darken it further. Moreover adding treble and presence to a real Plexi circuit only seems to increase the gain, or at least the perception of it. Especially presence.

I will continue to try IRs but as I keep saying, this IR does get me there on other devices?

Randalljax said:
I agree with the above
I think all 4 of the clips sound good
The NDSP are a bit thinner brighter, The Fractal fatter and thicker in the low mids
One thing I would try in the Fractal Plexi play with the bright cap values also turn up the high treble in the amp ideal page
Click to expand...

I’ll try the high treble. I haven’t really touched that as I’d assume the actual models would get there. I don’t really see that I should have to increase the bright cap beyond 5000pF??

rcm78 said:
There’s a couple tricks you can try. Try these one at a time.
Raise the Low Frequency Cut in the preamp tab. My VH preset uses a dimed SLP 1959 and I set low frequency cut to 350hz.
Raise the Negative Feedback up a bit.
Raise power tube bias from 60% to 70%.
With the bright switch on, lower the gain to 5-6. The model brightens up as you lower the gain. Raise the input trim to get the gain up to where you like it.
Get Leon Todd’s LTTVmix-7 IR. It’s a bright greenback IR. Leon is 2112 on the forum. His IR’s are available on his website and axe exchange.
Click to expand...

I’ll try all of this and report back.

giantslayer said:
1. Try turning the gain down, particularly for the tone in that first metropoulos clip.
2. Try turning Presence up.
3. What are your Speaker compression and distortion settings at? Lowering those might help.
4. I would also suggest experimenting with your guitar pickup height. Setting the pickups lower will yield a less compressed tone with more dynamics.
5. You’ll probably need a different IR to sound closer to those YouTube clips. Close mic’ing adds a certain girth to the notes, and pulling back the mic thins the notes in a way that is different from EQ. I would try to go for something where the mics have a little distance from the amp. Dynacabs are great for this. I personally like the ribbon mic as far back as I can put it.
6. I personally like messing with the negative feedback and transformer match parameters on a Plexi to make it feel tighter, more open, and less flat/compressed.
Click to expand...

1) It’s on 7, the Metropoulous is on 10.
2) It’s on 7. 10 does sound closer but not the same.
3) Stock values
4) Ok - possibly, but I don’t need to do this with the real thing or other models. Plus they’re pretty much at a stock height.
5) I’ll try this.
6) I’ll try this.

chris said:
If you want to thin it up, try reducing low end in the Input EQ that’s in the Amp block.
Click to expand...
Ok cool, I can try this. But I don’t need to do this with the real amp or other models?
 
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Random Hero said:
Thanks guys. I really don’t want this to come across is I’m digging out the product. I love the product. I also see a lot of “you’re doing this wrong or that wrong” but my point is that with either the real amp or models from other companies, it appears easier to get closer to this right away without going “under the hood” as it were and that surprised me. Searching the forum, I’m not the first to suggest a little darkness so I don’t think I’m completely nuts 😂
Click to expand...
maybe the specific amp modeled in the Axe is darker than the others.
 
Our modeling is at "speaker level". DI captures and the outputs of other products are at "speaker jack" level. The sound from the speaker is slightly darker than the voltage at the speaker jacks. So comparing other products through the same IR will always yield a slightly darker sound with Fractal products.

Also other products use static speaker impedance curves. We use dynamic speaker impedance modeling. When a speaker is driven hard the impedance at high frequencies decreases and the sound becomes darker.

IMO, the Fractal models sound far better than the other clips.
 
FractalAudio said:
Our modeling is at "speaker level". DI captures and the outputs of other products are at "speaker jack" level. The sound from the speaker is slightly darker than the voltage at the speaker jacks. So comparing other products through the same IR will always yield a slightly darker sound with Fractal products.

Also other products use static speaker impedance curves. We use dynamic speaker impedance modeling. When a speaker is driven hard the impedance at high frequencies decreases and the sound becomes darker.

IMO, the Fractal models sound far better than the other clips.
Click to expand...
Very interesting - thank you. I guess this does explain the differences.

I also think the Fractal models sound better, there’s much more depth and a 3D quality. It’s the high end.

I’ll keep tweaking.
 
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I tend to agree with the OP about the Marshalls in the Axe sounding quite dark but I'm basing this on the fact that I've actually used real Plexis and JCMs into a Suhr RL - tremendously bright, can get absolutely ear piercing and eardrum shattering. Is it pleasant when listening to it isolated? No, not at all. Does it work in a mix context? Hell yeah. That (and mids bumped at the right frequencies) is why these amps sit well with and cut the through the mix so well at the same time.
FWIW, I wasn't able to really compensate for this with the Axe.
Do I hate the Axe models? No, not at all, they sound perfect in every regard. But I miss that very high end sometimes.
 
Random Hero said:
Ok, but that makes it sound like user error. The same IR produces much closer to what I’m hearing otherwise with the capture and QC model - including with a real 50w I used to own - and the models have less of that sizzle and brightness inherently.
Click to expand...
Think of it not as user error but as philosophical rigidity that is causing you issues.

The QC is a different model. Your real amp has different component tolerances and in some cases different circuits than the Fractal models.

Using the same IR and expecting it to work is like expecting the same tires you use to go grocery shopping will also win you a NASCAR race.

Some IR files, whether due to the room recorded within, mic selection/placement, cab construction, speaker type/tolerances, and recording signal chain just handshake better with the amp model due to your amp settings, instrument, and playing variables.

One size does not fit all. Unless you are sitting in front of the same real plexi amp that was modeled by QC and Fractal simultaneously, the controls will be different settings to get the same resulting sound because of component drift and the inherent modeling differences.
 
Add a Post Phase Inverter Master and turn it down from 10 until you get your desired brightness.

That’s what I do and it will brighten and sizzle that Plexi right up.
 
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