My Sound Quality Axe-FX II Testing Results

R

relaxo

Inspired
I am working in a small song writing studio this month. I am recording final tracks on an album, so I did a couple hours of sound quality testing and this is what I found...

(To preface my results, "sound quality" is in the ear of the beholder and is OPINION, not fact. Also, we all may be using an AXE FX II, but we're not all hearing it even remotely the same. The monitoring chains, playing styles and room sizes and treatments vary wildly between us in these forums. I usually work in my studio Mercy Sound and exclusively play my Axe STD, Ultras and IIs through those huge Legacy masteingr monitors on the website. Through those, the Fractal Axes simply give the best tone I have ever heard in my life, beyond any album yet made in fact. Now, I am in a 5ft x 9ft untreated bare room with smaller monitors and my experience is still very positive, but not as overwhelmingly positive. Also, the fan noise which I thought was a non-issue in my big sound treated studio, is now an issue in this lively tiny bare room with no absorption. So, some of us should please stop arguing and speaking as if your experience is THE TRUTH. I used to be guilty of that folly even just two years ago.)


Now, on with this week's Axe FX II results:

TEST #1
A) Les Paul>Avalon 737 Pre >Mbox 3 Pro>SPIDF AXE IN
vs
B) Les Paul>Avalon 737 Pre>Analog rear Axe IN


(This test compares Mbox 3 Pro A>D with Axe A>D)


"B" sounded clearly fuller, nicer, more 3D and deeper.
Conclusion: Axe II has better A>D than the MBox 3 Pro

••••••••••••••••

TEST #2
A) Les Paul>Avalon 737 Pre >Mbox 3 Pro>SPIDF AXE IN
vs
B) Les Paul>Mbox 3 Pro>SPIDF AXE IN


(This test compared the 737 as a preamp DI with the MBox 3 pro.)


BIG surprise…draw…mbox sounded more exciting slightly, 737 richer and darker slightly.
Conclusion Mbox 3 Pro has a very decent DI preamp section!

•••••••••••••••
TEST #3

A) Les Paul>Avalon 737 Pre>Analog rear Axe IN
vs
B) Les Paul>Analog front Axe IN


(This test compared the 737 as a preamp DI with the Axe II as a preamp DI.)


"A" sounded clearly hands-down fuller nicer deeper.
Conclusion: $2000 Avalon 737 DI preamp sounds much better than built-in Axe FX DI preamp.


Note: All three tests were monitored with SPIDF AXE OUT>MBox 3 Pro analog outs.

••••••••••••••••
TEST #4

Testing from a few months ago at Mercy Sound using the five way mastering monitors showed that the digital output of the Axe II is FAR superior somehow to the digital outs of the Standards and Ultras. We use the Axe FX a lot on final takes at the studio and every single engineer chose analog outs on the STD and Ultra over the digital outs. The digital outs on the STD and Ultra sounded thin, hard and lifeless, shockingly similar to Guitar Rig and Amplitube to us. With the STD and Ultra, the analog outs into our high end preamps and then into the Digidesign 192 interface converters sounded hands down better (richer, more 3D, warmer, fuller, though less detailed) than the STD and Ultra spdif directly into the Digidesign 192 interface.

With the Axe 2, spdif directly into the Digidesign 192 interface sounded FAR better in every way (richer, more 3D, fuller, much more detailed) than the Axe II analog outs into the identical chain of high end preamps and then into the Digidesign 192 interface converters.

What did Fractal do in the II to improve the digital outputs so much? What an amazing surprise!
 
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Are these "blind" listening tests?

In other words, do you have one engineer that makes the connections and knows which is which and then a bunch of other engineers that listen to the two comparisons?

Or do you hook everything up and then tell people what they are hearing and ask their opinion?

If it is a "blind" test, have you ever tried telling them they were listening to something different without actually changing the connections?
 
Tests #1-3 were relatively quickie tests performed just by myself last week.

Test #4 consisted of two years of everyday experience with an Ultra, a Standard and a II with 10+ different engineers. No tricks/placebos were necessary...you knew instantly which was which. With any digital sound engine (not just Fractal products,) any engineer can clearly tell which output remains purely in digital and which goes analog when switched. The coloration that occurs when the digital output does the extra D>A then A>D dance is as clear as day, especially when run through even more layers of analog gear in between the DA and AD.
 
The Axe-FX II has a much lower noise floor than the Gen1; that might account for the differences in one part (IV) of your discussion.

Questions:

  1. Have you tested Guitar - Axe-FX II - USB - DAW yet?
  2. Why are you using the Avalon between the guitar and the Axe-FX?
  3. How does the Axe-FX II do in contrast to with/without the Avalon?
 
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Nice comparisons, any chance you have some clips? As you said, sound quality is subjective, and tone is a personal thing. Some people like dark, others like bright. Some clips might help.

Great review otherwise tho ;)
 
Um....how do I state this politely? Uh....I guess I can't, so I'll just say "ok". If you "hear" a radical difference between the A/Ds and preamps (all with specs that strain the discerning accuracy of test equipment), more power to you. Especially since the source material is a guitar modeler and you are listening in a 5ft x 9ft untreated bare room with fan noise.
 
relaxo said:
With the STD and Ultra, the analog outs into our high end preamps and then into the Digidesign 192 interface converters sounded hands down better (richer, more 3D, warmer, fuller, though less detailed) than the STD and Ultra spdif directly into the Digidesign 192 interface.

With the Axe 2, spdif directly into the Digidesign 192 interface sounded FAR better in every way (richer, more 3D, fuller, much more detailed) than the Axe II analog outs into the identical chain of high end preamps and then into the Digidesign 192 interface converters.
Click to expand...

The digital output is a direct link to the data coming from the processor. So if you prefer the digital output sound on the II that just means you prefer the algorithms in the 2. There's no "secret sauce" that we apply to the digital data in the II vs the Std/Ultra.

My hunch would be that your high-end pre-amp add some pleasing high frequency roll-off or other colorization. I would assume you prefer this colorization on the Std/Ultra because the quality of the amp modeling and/or the IR's you were using was not as good as it is in the II.

You didn't mention if you tried the analog outputs directly into the Digidesign interface without your pre-amp (unless I missed it)? If you did, I would expect it to sound virtually identical to the SPDIF directly into the Digidesign. So it seems to me it is the extra pre-amp stage that is coloring things when you go analog and the difference is not the SPDIF vs Analog outputs of the Axe-FX.

Hope this is helpful.
 
steadystate said:
Um....how do I state this politely? Uh....I guess I can't, so I'll just say "ok". If you "hear" a radical difference between the A/Ds and preamps (all with specs that strain the discerning accuracy of test equipment), more power to you. Especially since the source material is a guitar modeler and you are listening in a 5ft x 9ft untreated bare room with fan noise.
Click to expand...

When I play, fan noise becomes almost irrelevant, I like medium rock volumes. Some tests resulted in strong differences, others surprising little difference. Tests 1-3 in the small room should be taken with a grain of salt. Even if they are accurate or not, what does it matter to the vast majority of Axe users?

But test #4 is huge. The Ultra and STD overwhelmingly sounded better via analog outs and the II strongly sounds better with digital outs in my opinion.

AdamCook said:
You didn't mention if you tried the analog outputs directly into the Digidesign interface without your pre-amp (unless I missed it)? If you did, I would expect it to sound virtually identical to the SPDIF directly into the Digidesign. So it seems to me it is the extra pre-amp stage that is coloring things when you go analog and the difference is not the SPDIF vs Analog outputs of the Axe-FX.
Click to expand...
My career is testing and choosing equipment at my studios and I did test the analog outs of the three Axes directly into the analog ins of the Digi 192 converter on numerous and different occasions. I already described the sound of the Ultra and STD digital outs. To me, the Axe II analog outs sound less clear, less detailed, about equally and in the same range as the II's digital outs in mid and bass weight. The analog outs have a honker midrangey tone as a whole than the II's digital outs and can be defined as more lo-fi. The II's digital outs are far more spacial (3D.) I have found on my 100's of discussions on Gearslutz regarding the Axe that many people prefer a lower-fi tone to the pure goodness of superb, rich and full digital outs, especially when it comes to guitar tone because it's what they're used to with tube amps, paper cones and worst of all, tone sucking mics>analog recording chains…very lofi compared to excellent digital. It's all in the ear of the beholder.

But Adam, there is a very sizable difference between digital and analog outs on all three Axes directly into the Digi 192 interface, even with all peripheral analog gear bypassed. I would feel 100% comfortable laying $1000 on the table that I could pick which was which, it's that stark. Now, again, not better for all, but different. Other people with very different quality of A>D interface converters, monitoring chains, rooms and ears may experience vary different results and easily find the analog outs more to their liking.

AdamCook said:
There's no "secret sauce" that we apply to the digital data in the II vs the Std/Ultra.
Click to expand...

I couldn't have described it better, it does seem like there is a secret formula discovered and added to the Axe II. Not that the analog outs are bad or worse than the Ultra's. They're excellent. It's just the the didgital outs of the II sound so amazing! It makes me want to use USB I/O rather than spdif with my Mac so badly for the workflow benefit, but I can't....but huge problem that's been covered in other threads in the bugs forum.


PS my font got messed up, what's the standard font and size in here?

 
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relaxo said:
But Adam, there is a very sizable difference between digital and analog outs on all three Axes directly into the Digi 192 interface, even with all peripheral analog gear bypassed. I would feel 100% comfortable laying $1000 on the table that I could pick which was which, it's that stark. Now, again, not better for all, but different. Other people with very different quality of A>D interface converters, monitoring chains, rooms and ears may experience vary different results and easily find the analog outs more to their liking.
Click to expand...

relaxo. . . have you looked at the signal chain within the Digi 192 interface? Is the digital input signal path and the analog input signal path identical? Are they truly "apples to apples", or could it be that something in a signal path is causing the difference you hear? For example, perhaps the digital signal path bypasses some audio circuitry that is causing a degradation with the analog input.

Terry.
 
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