VIDEO: Mesa Dual Rectifier vs Kemper vs Axe-Fx III vs Helix (FREE RIG!)

  • Hey everybody I'm Mikko and this is my first post. :) I've been a Kemper owner for quite some time now and finally found the courage to start a conversation on this forum. You're most likely not familiar with my company "ML Sound Lab", I'm best known for creating some of the highest quality impulse response collections on the market. I've been labeled the "djent IR guy" as I've made the IR's that Periphery and many other djent bands use both live and in the studio. (Periphery III is a good example) I'm definitely more of an alternative-prog-rock guy myself. Anyways today I shot a pretty cool video comparing my Dual Recto to some of the modelers that I own which includes the Kemper obviously and also the Axe-Fx III and Line6 Helix. My aim here was to try and bring some peace to the "modeler war" as I believe all of these modelers are capable of sounding amazing. Check it out:


    External Content www.youtube.com
    Content embedded from external sources will not be displayed without your consent.
    Through the activation of external content, you agree that personal data may be transferred to third party platforms. We have provided more information on this in our privacy policy.


    Feel free to try out the rig, that's the sound of my blue and flowery Dual Rectifier. I've been thinking about expanding "ML Sound Lab" to also create Kemper profiles as I do have quite an impressive collection of gear including everything from Woodstock era Marshalls to modern high gain beasts and I've been creating guitar tones professionally for about 5 years now. After months of trying out different "profiling methods" I've finally discovered a way to perfectly capture my real amps and cabs separately while they still react with each other. I really don't like the idea of having separate profiles for studio and powered cab use. The way I do profiles should work perfectly for both use cases. The free rig you can download was done using my "secret methods" if you want to try it out. Oh and... I don't really know many Kemper users and I would love to have active beta testers. If you're interested in doing some beta testing for me please contact me through conversations and tell me about yourself.


    I hope this is all well-received here as I'd love to be a part of the conversation. :)

  • Nice, good demo. They're all close, but I do notice that the real amp just has a little something more than any of the modelers, I can't explain what but it just feels a little more complex and clean.

    My take on this was, they're all really close but if I'm nitpicking then -

    1. The AxeFX sounded the closest, but had a strange very subtle phasing/filtery effect underneath it.

    2. The Helix was very similar to the Axe but ever so slightly less low mids/bass or more pronounced upper mids, it didn't have the same filters effect but something felt flat.

    3. The Kemper seemed to have a more fuzzy/muddy tone for some reason than the others and a little less dynamic range. It sounded almost lo-fi like there's some clipping or SPDIF sync issue or some other jitter like fizz going on.

    While the differences were indeed subtle this is the first time in these shootouts where I've felt the Kemper was behind noticeably and in a way that makes me question if it's now simply getting too long in the tooth and may need an update that increases the frequency curve resolution in the OS or I even wonder if that is fixable in software at all ;(.


    I listened to them both through my studio monitors and then also through my CrapMac(tm) laptop speakers which might seem silly, but I find that because they are solely about the upper mids and treble they can be quite revealing of subtle differences that may be hard to discern from larger monitors where they're competing with the energy from the lower end.

  • I asked my wife to watch your video and give me her impressions as to which units sounded more like the real amp. She had no idea that I owned one of them and I intentionally did not tell her until after she gave me her opinions. FWIW, she has zero knowledge of gear. Everything is a thingy?.



    She said the Helix sounded tinny, that the Kemper (Green Thingy) sounded identical, and the 2nd Thingy (Fractal), was fairly close, but still sounded a little off compared to the Green Thingy.


    I happen to agree with her completely?


    Way to go Green Thingy from my wife, and I’ll say way to go for the really good profile!!!!

  • First of all thank you for the warm welcome guys. After using modelers and tube amps side by side for almost a decade now I've sort of decided to approach these things with a healthy attitude much like the ask-my-wife approach by Barry. There's an unlimited time of tweaking that you can do both with real amps and modelers. When creating these versus videos it's always really hard the volume balance the clips in a fair way and most of the time people will prefer the sound that's louder so just imagine how much time I spent trying to volume balance these clips by +-0.1dB here and there. Even though I can measure a difference I do feel quite confident that a large majority of people would not be able to tell which is which in a blindfold test and obviously the most important part is that all of these sounds "sound real" be it a modeler or a tube amp.


    Of course I could've continued tweaking to get the sounds closer and this was a really quick test, actually I could've created match EQ IR's for each modeler but I wanted to keep the test fair and realistic. I'm going to post a spectrum analyzer picture below but before I do, I want to make it clear that every tube amp sounds different and there are different versions of the Dual Rectifier with different brightnesses and all that. Also cabinet modeling will naturally add a low cut at around 100hz and a high cut starting at 4khz and inbetween those frequencies I think all modelers did a really good job. Here's what this comparison looks like WITHOUT CABINET MODELING:


    [Blocked Image: https://i.ibb.co/T02CwHh/justtheamps.png]


    White = Recto. Green = Kemper. Blue = Fractal. Red = Helix.


    Personally I feel like the biggest difference was the amount of gain between the modelers. I maybe got just a little bit more gain and saturation on the Kemper when compared to the real amplifier. The Fractal was a little bit cleaner and actually I fine tuned the Helix gain pretty well. The real Mesa amp has a resonant peak at around 80hz which was a bit hard to get from the modelers but like I said before, an IR will naturally cut the lows from about 100hz down so it's not a big deal. Then at the opposite side of the spectrum (literally) you'll see how all modelers handle the uber high frequencies which also gets cut by IR's almost entirely. This is where I had to do some tweaks to get the modelers to line up with the real amp which I believe comes down to which ever revision of the Recto was modeled for these units. Anyways all the "differences" are mainly due to this being a rather quick test and me not taking the time to really fine tune everything. I'm pretty confident that I can get the sounds even closer though already it's really hard to hear a difference even though you can measure it.


    So I'm sure you now understand how much of a geek I really am. :D

  • Here's what this comparison looks like WITHOUT CABINET MODELING:


    [IMG:https://i.ibb.co/T02CwHh/justtheamps.png]

    White = Recto. Green = Kemper. Blue = Fractal. Red = Helix.

    So.... assuming those are accurate plots (and I assume they are), they show why a lot of people hear a certain "Kemper sound" up in the highs, especially on non-Marshall distortion profiles. You can clearly see the peaks between 5-7k and the extra high end content above 11k. I'm super interested in seeing if more plots results show the same relationships across other profiles.


    It's a perfect example of why we need high- and low-cut in the cabinet block.

  • Welcome and there's always place for one more good new vendor here and I'm looking forward to your profiles eventually. :thumbup:

    Think for yourself, or others will think for you wihout thinking of you

    Henry David Thoreau

  • So.... assuming those are accurate plots (and I assume they are), they show why a lot of people hear a certain "Kemper sound" up in the highs, especially on non-Marshall distortion profiles. You can clearly see the peaks between 5-7k and the extra high end content above 11k. I'm super interested in seeing if more plots results show the same relationships across other profiles.


    It's a perfect example of why we need high- and low-cut in the cabinet block.

    Hey it's great to see a familiar face! :)


    I think in the right hands all of these units are fully capable of replacing tube amps. That graph I posted is a millisecond snapshot of the same riff being played through all units so it's a very unforgiving graph to look at since it reveals differences in dynamics more than your regular match EQ which might be a 10 second graph comparison. The problem areas for all modelers are the super low end and the super high end which ultimately is inaudible in a mix context however my aim will always be getting rid of all differences in the end. I most definitely can get all of these modelers even closer. This was limited to a 5min tweak process for comparisons sake.


    I've found that there's a lot that goes into profiling "as accurately as possible" which is something I've been trying to study ever since I got the unit. Obviously I'll keep most of my findings somewhat secret but I can discuss some general topics for sure. Signal volume levels are super important and a bit hard to monitor to be honest. Refining is extremely powerful as in it can make or even break your sound. So I don't really believe there is a "certain Kemper sound" but rather you can do something in the profiling process that can make certain profiles sound a certain way.


    But sure, high and low cut in the cab block would be great. PA speakers don't sound too nice way up high especially.

  • Messed around with free profile. Added in a green scream, EQ in X slot, chorus,reverb. No post editing. I am not sure how this sounds, as I am unable to completely hear with my right ear due to a head cold.


    External Content soundcloud.com
    Content embedded from external sources will not be displayed without your consent.
    Through the activation of external content, you agree that personal data may be transferred to third party platforms. We have provided more information on this in our privacy policy.

  • I was looking into maybe swapping my Kemper for a AxeFX II when I heard a demo where the AxeFX sounded clearly a bit better, and I thought it might be nice to have something that was more “amp like” when tweaking.


    I quickly got over that. I poured over dozens of demos, and it seemed to be a crap shoot as to whether the AxeFX beat the Kemper or vise versa. The conclusion I came to was, if the Kemper sounded worse, it was most likely due to how the profile was made or tweaked. I don’t think that even the AxeFX III is better than the Kemper. It’s just a different approach.


    One other thing I am noticing is, that I think for some types of amps, especially high gain models, it’s probably better to profile it with a DI/load box of some sort, and then use a cabinet from another profile or a converted IR.

  • I slightly adjusted the profile from my last clip. Added back the mids. I still cannot fully hear out of my right ear ;(


    *Since my guitar is setup for low tuning. I tuned it to B standard and played the riff on the higher strings.


    External Content soundcloud.com
    Content embedded from external sources will not be displayed without your consent.
    Through the activation of external content, you agree that personal data may be transferred to third party platforms. We have provided more information on this in our privacy policy.

  • Nice work Mikko

    Listing through my 1 headphone work earpiece ( but NOT watching the video) I couldn't hear any difference. I think that says:

    1) the differences are so small that only someone really listening back to back will notice i.e. Joe Public won't

    2) I'm too lazy/deaf to care about detailed nuances

    3) all units ( as I think we all agree) are really top notch.


    What a great time to be playing guitar!