Dimed Real Plexi VS Dimed Simulation [Q8.01]

Slammin Mofo

Inspired
Here's a comparison between an Axe FX II Plexi simulation and my Mojave Scorpion amplifier:

FAS Plexi: https://instaud.io/VAM

Mojave Scorpion: https://instaud.io/VAN

EDIT: New comparison clip with matched EQ (first Mojave, then FAS Plexi)

https://instaud.io/VGx

Code:
The following setup was used for the Axe FX II Plexi Simulation:

Guitar (Duncan JB style Humbucker) -> Axe FX II (1959SLP Jump) -> UAD Apollo (no effects and no level adjustments) -> Logic Pro X

And this was the Mojave Scorpion setup:

Guitar (Duncan JB style Humbucker) -> Dimed Mojave Scorpion -> Suhr Reactive Load -> UAD Apollo (no effects and no level adjustments) -> Logic Pro X

The Logic signal chain was identical for both tracks: Rosen Digital Pulse IR Loader -> Valhalla Vintageverb ConcertHall preset -> Soundtoys Echoboy Jr. Dotted 8th Plex preset

I used the PIN 68 G12M20 (Idealised Null Amp/SINGLE_MICS_MPT) Impulse Responses of cabIR.eu:

MR-PIN68_A_421_M2_I.wav              100% left           0.07ms delay

MR-PIN68_room_414_M2_I.wav        100% right

Anyway....

What do you guys think? I have played around with all the different Plexi simulations and with some advanced parameters, but eventually I chose the 1959 SLP Jump model and I only changed the preamp tube type to Sylvania and increased the Motor Drive to 5.2.

Overall, I'm impressed by the Axe FX's Plexi simulations, however, one peculiarity that I just couldn't achieve with any Plexi simulation is the high-end "chirp" for lack of a better word. It becomes very apparent once I really start digging into the strings. Is there any advanced parameter that will get me closer to the real thing?
 
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To eliminate most of the EQ differences, I matched the EQ with an Ozone plugin. This is the result:

https://instaud.io/VGx

It sounds very close, but there's still something in the Scorpion top end that's not there in the Fractal version. Can you hear the "squishing" that happens in the Scorpion clip? I know it's just a detail, but every real cranked Plexi clip I've heard has that squish or chirp. You can hear it in this clip, too:



Is there a way to make the Fractal Plexi top end response a bit more similar to the real world equivalents?
 
It sounds to me like the Scorpion has less lows / more upper mids and highs in the preamp stage than the 1959SLP. Tone matching after the amp won't change the character of the amp compression. What if you put a tilt EQ or shelving EQ in front of the 1959SLP with the highs and mids emphasized?
 
Can you hear the "squishing" that happens in the Scorpion clip?

Compared to the EQ'd Axe clip? Not really. Just boosting the high end around 4.6k a couple of dB brings out the chirping. To my ears, the bigger difference I heard after boosting 4.6k was in the lows and mids. I'm pretty sure most listeners would have trouble differentiating the two in a blind test though, after EQ'ing that is.

There's probably a parameter that will accentuate the high-end chirp and squish you're referring to.
 
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I did a second try with an EQ block in front of the Fractal SLP. I increase the highs and lowered the mids a bit. Afterwards, I applied the Ozone matching EQ again.

https://instaud.io/VGV

I expected the Fractal amp to squish more, now that the EQ has lowered the low end and increased the high end that the preamp receives, but I still don't hear it.

The youtube clip above also features a Plexi replica loaded down with the Suhr reactive load, and even though the guy has used different IRs, I still hear that there are more commonalities in the top end and low end between the Mojave and the Suhr than between the Mojave and the Fractal SLP. That's why I'm doubting that this is mostly due to EQ differences, be it in front or after the amp.
 
Yes, I've played around with the supply sag parameter. I also played around with power amp hardness, negative feedback, variac, motor drive, PI shift, preamp tube hardness, transformer match etc. to no avail...
 
Try this. Boost 4669Hz by 2dB and cut 674Hz by 4.5dB using a Parametric EQ block. I tried it with your Fractal sample and this is the result:

https://instaud.io/VBB

Compare that to your original Mojave Scorpion sample:

https://instaud.io/VBD

Almost identical.

This was pretty impressive.

I heard 'squish' in different places there, and ended up thinking the Fractal version was a touch better (there was just a *hair* of brittle on the Scorpion on a few places...) But honestly, when it's this close, it's really opinion...both sound great.
 
Here's a comparison between an Axe FX II Plexi simulation and my Mojave Scorpion amplifier:

https://instaud.io/VAM

https://instaud.io/VAN

EDIT: New comparison clip with matched EQ

https://instaud.io/VGx

Code:
The following setup was used for the Axe FX II Plexi Simulation:

Guitar (Duncan JB style Humbucker) -> Axe FX II (1959SLP Jump) -> UAD Apollo (no effects and no level adjustments) -> Logic Pro X

And this was the Mojave Scorpion setup:

Guitar (Duncan JB style Humbucker) -> Dimed Mojave Scorpion -> Suhr Reactive Load -> UAD Apollo (no effects and no level adjustments) -> Logic Pro X

The Logic signal chain was identical for both tracks: Rosen Digital Pulse IR Loader -> Valhalla Vintageverb ConcertHall preset -> Soundtoys Echoboy Jr. Dotted 8th Plex preset

I used the PIN 68 G12M20 (Idealised Null Amp/SINGLE_MICS_MPT) Impulse Responses of cabIR.eu:

MR-PIN68_A_421_M2_I.wav              100% left           0.07ms delay

MR-PIN68_room_414_M2_I.wav        100% right

Anyway....

What do you guys think? I have played around with all the different Plexi simulations and with some advanced parameters, but eventually I chose the 1959 SLP Jump model and I only changed the preamp tube type to Sylvania and increased the Motor Drive to 5.2.

Overall, I'm impressed by the Axe FX's Plexi simulations, however, one peculiarity that I just couldn't achieve with any Plexi simulation is the high-end "chirp" for lack of a better word. It becomes very apparent once I really start digging into the strings. Is there any advanced parameter that will get me closer to the real thing?



Those clips has quite a big differense. I miss lots of stuff in the fractal version. maybe increase speaker drive or motor drive or the balance between normal and bright gain. There´s no hair on the axe clip.
 
Those clips has quite a big differense. I miss lots of stuff in the fractal version. maybe increase speaker drive or motor drive or the balance between normal and bright gain. There´s no hair on the axe clip.

Are you refering to the comparison clip where both amps can be heard in the same clip or are you just talking about the two individual clips that I posted at the very top?

Here's my third attempt:

https://instaud.io/VSV

I increased dynamic presence and crunch quite a bit, as well as motor drive, speaker drive, harmonics and I put a tilt EQ in front of the Plexi simulation. I basically did everything to accentuate and enhance the top end, even to the point of exaggeration, just to let that top end shine through. The clip was also matched to the Mojave EQ response with Ozone.

I still don't hear it. The top end response is just not the same. You can hear it in this clip, too:



Every cranked Marshall Plexi has that distinct sizzling top end that I just can't get no matter how much I play around with the advanced settings. We can argue that there are minor differences between each manufacturer, but at the end of the day, those are still just Plexis. It should be possible, even without advanced parameters, to get a similar response from one of the many Plexi models inside the Axe FX II...

Have you ever dialed in a Plexi tone with the Axe that had that elusive top end, Thomas?
 
Am I missing something, you are comparing an marshall plexi to a Mojave scorpion? And they sound different? marshall plexi's against marshall plexis sound different, let alone it's a totally different amp.
 
Am I missing something, you are comparing an marshall plexi to a Mojave scorpion? And they sound different? marshall plexi's against marshall plexis sound different, let alone it's a totally different amp.

No, that's not what I'm getting at. I've posted a video of a Suhr SL68
and the top end response is almost identical to my Mojave clip, and keep in mind that I've used a different guitar, a different Humbucker and different IRs, which just goes to show that, even though there are differences between a Suhr and Mojave, the top remains almost identical.

Real Marshall Plexis, Suhr Plexis and Mojave Plexis have far more commonalities than differences. I've also played a couple of real and cranked Marshall Plexis and they sound very similar to my Mojave Scorpion, sizzling top end included.

Here's a clip of a real Marshall Plexi:



Even though he's using a Les Paul with no JB Humbucker in it and a different speaker, the basic character of the amp is similar to my Mojave clip. Can you hear that top end squish once he digs in?
 
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I've posted about this before. In the real amps you can hear a percussive impact, more rasp and more thump (what's being called 'chirp' here). I don't know how to dial that in. The closest I've come is with dialing dynamic presence way up, dynamic depth up a bit and sometimes pick attack.

Here's a plexi clip I did (using a semihollow).


The original has much more percussive bounce.
 
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