Analog vs. USB recording in Axe fx II!

Izzyprad

Inspired
Hello,

I have been thinking about this topic a lot for past couple of weeks. I know Axe FX II includes USB interface (thank god, finally!), so if I were to do some pro studio recording with Axe FX II, wouldn't it be the best to use USB port into a DAW rather than going through analog cable method? Wouldn't that minimize signal degradation?

What concerns me the most is when doingre-amping. That's when your signal goes through multiple converters (A/D, D/A).

So let's see, if I were to do re-amping using USB in Axe FX-II, then it would be....

>Record dry guitar signal to DAW (A/D conversion)
>When reamping, send recorded digital signals to Axe FX for processing (Digital to digital - no conversion)
> All calculations in Axe FX (Digital)
> Record wet signal back into the DAW (Digital to digital - no conversion)
So here your guitar signal only goes through one A/D conversion.


No let's see for using analog cable method....

>Record dry guitar signal to DAW (A/D conversion)
>When reamping, send recorded digital signals to Axe FX for processing (D/A conversion)
>Axe Fx reading the signals (A/D conversion)
>All calculations in Axe FX (Digital)
>Axe Fx outputs wet signal (D/A conversion)
>Record wet signal back into the DAW (A/D Conversion)
So here your guitar signal goes through FIVE conversions! That's a lot!


Does that sound right? So USB recording is better than using Analog cables?
 
Wouldn't that minimize signal degradation?

When recording instruments like electric guitars that tend to have harsh frequencies at times, signal degradation can be the recording engineers best friend. Further, signal degradation can be the whole vibe of a smash hit like the Strokes or Phil Specter's wall of sound. What kind of tone do you want for your particular track?


Regarding USB vs analog outs, not being snotty, but being real...listen for yourself. Record tracks with analog outs and record them via USB and then compare. A lot will depend on your A>D converters on the analog side. In pro studios, engineers that love Axe FX I nearly exclusively use analog outs. People are not used to the pure digital sound...yet. With USB direct audio on Axe FX II, it is possible that Fractal has adjusted the tone of the digital so it's not so "pure digital" sounding like the old SPDIF outs. Pro studios have the advantage of amazing converters and many of you may well prefer the USB outs on Axe II, even if they are still unmodified "pure digital."

Also tone is as subjective as taste. Coke or Pepsi? Experiment everyone to find what YOU want. Elbow grease!
 
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I'm going to experiment with this. Will use 3 methods.

1. Direct via USB
2. Direct via S/PDIF
3. Direct via Analog outs

I'll let you know what I come up with.
 
Reminds me of when I was a naive recording engineer in my first year. I was on the forums b*tchin' every week that my digital synth didn't have digital outs and that made no sense. "Why go through D>A and then A>D again in the DAW when we should be able to go right into the DAW digitally?! Why have all the unnecessary signal degradation?!?! Arrrgggh," I moaned. But everyone around me making real albums who had digital outs still used the analog outs. I thought "that's lazy, old skool thinking. They should use the digitals out's It will sound so much better." Then I grew some different ears. Now I almost always ignore my digital outs and choose analog outs. I find it's a sound that fits better into my rock and pop mixes. Analog outs usually "feel" better in the mix and require less EQ (to me.) Also, what sounds good solo'ed is not always the same as what fits into the 24 track mix.

But digital sounds wonderful now compared to ten years ago. Yes, if you want detail and sonic information, you might choose digital direct. If you want your Axe to sound more like guitar sounds you've heard your whole life, you might choose analog outs.
 
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I'm going to experiment with this. Will use 3 methods.

1. Direct via USB
2. Direct via S/PDIF
3. Direct via Analog outs

I'll let you know what I come up with.

Thanks bkrumme. Will anxiously await your results. I have a firewire interface that I was using for midi and recording, but with the Axe II's USB interface I was hoping to just offload since it would put a good $250 back into my pocket (which is always appreciated!).

Look forward to what you find!
 
I'm curious about this, I was assuming that the best way to record from the axe-fx II would be through usb
 
I'm curious about this, I was assuming that the best way to record from the axe-fx II would be through usb

Easiest, definitely. Best, not necessarily. What's "better" could be different for you than it is for me.

For instance, with USB and S/PDIF, I'm locked into 48kHz/24bit. With the Analog outs, I can crank up my DAW to 96kHz. While it may not make much difference during the recording process, it WILL make a difference when I bounce the project down to WAV/MP3 since there are more samples to take away from when encoding.

All of this will be part of my tests. At the end of the day, though, it will all boil down to what sounds better to you.
 
Thanks for the info guys. Yeah I was hoping the same thing. I use RME Fireface 800 as my converter, and it is freaking expensive ($1800). I was hoping that if I use USB for recording, then that would allow me to sell this beast. hmm... I guess not.

I will anxiously wait for the result.
 
Thanks for the info guys. Yeah I was hoping the same thing. I use RME Fireface 800 as my converter, and it is freaking expensive ($1800). I was hoping that if I use USB for recording, then that would allow me to sell this beast. hmm... I guess not.

I will anxiously wait for the result.

You certainly COULD forego the Fireface 800 and still get very good results. The few recordings I've done with USB on the Axe II have turned out like any other 48kHz recording. The question you really need to answer for yourself is whether you need the Fireface 800 for OTHER instruments. You certainly *could* record vocals with the Axe II, but you're not going to be able to mic up a drumkit.
 
You shouldn't find any signal degradation over USB reamping. There shouldn't be any d/a or a/d conversion in the process, 1's and 0's is all it is.
 
I don't have a dog in this fight so to speak, but I've noticed a strange shift recently. A few, some high profile, Axe users advocated analog out over S/PDIF for recording in the recent past. However, with their new AXE II, they are tossing up recordings and glowing about the positive attributes of the USB audio: USB digital streams should be no different than S/PDIF it seems to me. Like I said, I don't care either way.

just sayin

enjoy
 
I don't have a dog in this fight so to speak, but I've noticed a strange shift recently. A few, some high profile, Axe users advocated analog out over S/PDIF for recording in the recent past. However, with their new AXE II, they are tossing up recordings and glowing about the positive attributes of the USB audio: USB digital streams should be no different than S/PDIF it seems to me. Like I said, I don't care either way.

just sayin

enjoy

I don't know the technical details, but Cliff explained last year why S/PDIF wasn't the first choice, over analog outs. Something to do with the way S/PDIF could degrade your signal, anyway it's an older thread, the info is there...
 
I did not know that the USB output are sampled at 48kHz (as SPDIF). I thought it would be at 44.1Khz. If USB output is in 48 Khz, then I can understand the why someone would prefer Analog over USB/SPDIF.
 
Hey... it's not like we are recording on tape these days.
Why don't you record both?..... for a while, until you form an opinion about the issue.

;)
 
Thanks for the info guys. Yeah I was hoping the same thing. I use RME Fireface 800 as my converter, and it is freaking expensive ($1800). I was hoping that if I use USB for recording, then that would allow me to sell this beast. hmm... I guess not.

I will anxiously wait for the result.

I have the Fireface UFX and it's sweet! I had the FF800 until a friend stole it :). If you are just recording the guitar then no biggie tossing it but for mult vocals or other instruments not so much. The UFX is kinda cool in that as a stand alone with the II and no PC I can record direct to a USB thumbstick or external drive. So many more options!
 
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You certainly COULD forego the Fireface 800 and still get very good results. The few recordings I've done with USB on the Axe II have turned out like any other 48kHz recording. The question you really need to answer for yourself is whether you need the Fireface 800 for OTHER instruments. You certainly *could* record vocals with the Axe II, but you're not going to be able to mic up a drumkit.

I guess I should have read the whole thread before replying above! :)

Couldn't agree more with you. I am interested to see your results from the compare. I had compared the SPDIF and Analog on the Ultra and could not tell a difference to my ears. Maybe I too will do a 3 way compare with the USB included. So much to do with all the new stuff!!! This day job is really starting to interfere!!!
 
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I guess I should have read the whole thread before replying above! :)

Couldn't agree more with you. I am interested to see your results from the compare. I had compared the SPDIF and Analog on the Ultra and could not tell a difference to my ears. Maybe I too will do a 3 way compare with the USB included. So much to do with all the new stuff!!! This day job is really starting to interfere!!!


My understanding is, most people try to avoid SPDIF because of sampling rate issue. SPDIFs are sampled at 48 khz, while the standard CD format is in 44.1 Khz. So, if you have other tracks recorded at 44.1 Khz, and guitar track at 48 Khz in the same project in your DAW, then your DAW can puke. Atleast it used to back then. Another issue is when doing the final mixdown (assuming your DAW didnt puke). When your DAW converts 48 Khz to standard 44.1 Khz (CD) there is some signal degradation.

But some do hesistate to use SPDIF because they say it sounds somewhat "Digital". But it's all subjective. Depends upon what you are trying to achieve, I guess.
 
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Alright guys. Here's a clip of all 3 methods. Same riff three times once with USB, once with Analog and once with S/PDIF.

 
People are not used to the pure digital sound...yet. With USB direct audio on Axe FX II, it is possible that Fractal has adjusted the tone of the digital so it's not so "pure digital" like the old SPDIF outs.

There is no such thing as listening to "pure digital". The signal has to be converted to analog in order to hear it.

With all the delicate work that has gone into the axefx to make it accurately model an analog system, it makes zero sense to intentionally degrade the signal quality by going D/A - A/D.

The only valid reason to use the analog output is if your project is at a sampling rate other than 48khz, as described above.
 
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