Home Studio Line 6 POD POD X3 (Live) Tips and Tricks recording The Digital Age Tracking

Analogue versus Digital: Can YOU tell the difference?

As digital gear becomes more prevalent I see the same question asked over and over again, “Should I record using the analogue outs or use the USB (or S/PDIF) outputs?” The popular answer is, “keep it digital or you’ll lose sound quality!” Is there any merit to this claim that sound quality is lost if you do not “keep it digital” all the way? Does it matter in a home recording studio which you choose? Let’s find out.

The audio files

Following are three sound files. They are all a guitar playing through a Line 6 POD X3 Live. One take was recorded to three stereo tracks simultaneously using the USB driver for POD X3, the 1/4″ outs of X3 into the 1/4″ ins of an Echo Layla, and the S/PDIF out of X3 into the S/PDIF in of the Layla. There is absolutely no post-processing done on any of these tracks. Here are the files: sample A, sample B, sample C. You can guess Layla analogue, Layla digital, or POD X3 USB for each track. Email your guesses to [email protected]

Analogue versus Digital: Expected results

No “scientific” experiment is complete without stating your expected results. I have listened to the sound files myself in blind testing. With enough responses I fully expect there to be no clear winner. The real result I hope to achieve is the illustration that it does not matter. The gear of today is so capable in all modes of operation that you will get musically usable, pro sounding results no matter which outputs you use. Let us spend less time quibbling over theoretical differences in sound quality and undetectable additional A/D to D/A conversions and more time making music. That is, after all, what draws us together as a community to have these discussions in the first place.

I will hold off posting the results until I get enough responses. I’d like to get at least 1000 responses before posting results so it could take a while. Post on your favorite audio forums and get people involved taking this test. I’d love to have as many perspectives as possible. Spread the word!

Line 6 POD X3 LIVE Guitar Multi-Effect Pedal
Line 6 POD X3 Live
This is the preamp/modeler used to create the sound clips on this page. One of the sound clips is recorded using the USB drivers of this unit.
price check
Musician’s Friend
Guitar Center

Echo Layla3G PCI Audio Interface
Echo Layla
This is the soundcard used to record the “other” two samples. One sound clip went through the analogue inputs while the other went to the S/PDIF input. This is a great home studio soundcard with great converters.
price check
Musician’s Friend
Guitar Center

Live Wire S/PDIF RCA Data Cable 1 Meter
Live Wire S/PDIF
This is the cable I used for the S/PDIF part of the test. S/PDIF comes in a few flavors that include optical. If you are going to be doing some digital recording make sure you get the right cables. The S/PDIF cables with RCA ends are coaxial (coax) while the ones with TOSLINK ends are optical.
price check
Musician’s Friend
Guitar Center

Test results

I was holding out for 1000 responses and now have the required number of guesses. With a thousand responses there were 1.2% percent of correct answers, and I suspect a few of those were just luck. The correct answers are

  • A = analogue signal
  • B = digital via S/PDIF
  • C = digital via USB

NOTE: There has been some discussion about the 1.2% figure and what would be the likely correct percentage if everyone was truly guessing. There has also been some suggestion that the 1.2% means people hear the difference but it is the opposite of what they expect. I would like to say that I agree with the theory of those conclusions but they are also incorrect. The reason we have such a low (1.2%) of correct guesses is that the many participants did not submit guesses but instead gave up at, “I don’t have a guess, I just can’t tell.” I counted those hundreds of submissions as incorrect.

Could you tell the difference? I hope this has served to illustrate the point that you don’t need to worry so much about ideal signal flow or additional analogue to digital conversions. You’re going to get great results no matter which path you take for your home studio recordings. You will make much better recordings if you focus more on inspiration/creativity than worrying about the ones and zeros. Have fun!

20 replies on “Analogue versus Digital: Can YOU tell the difference?”

These sound absolutely identical. I couldn’t even make an educated guess. I’m so damn tired of people ripping line 6 stuff, or for that reason, any modelers… all the wonder has left this world. 20 years ago, if someone handed you a weird shaped electronic thing and said, this models hundreds of amps and effects with 95% accuracy, is SOME tone quality a sacrifice you’d be willing to make?

Your blog is important in dispelling these crap myths. Thanks.

Dude your a liar that sound is the same XD LOL

jaja its the same sound for me cant get it really :D

If I had to guess, A would be the pure digital, B and C sounded a little “browner” to coin an EVH tone description. I guess B and C were a little rounder and slightly more musical, but I couldn’t differentiate any more than that between B and C. So that’s my 2 cents. Looking forward to the results. I really appreciate the effort you are putting into dispelling the myths.

Rock On!

Close, very differences in all those.. Im going to have to say number one was analog……….two was the USB…………..and three was S/PDIF out of the X3….
I just bought a X3 and cant wait to see if it will do what I want it to…

Just to compare the sounds means the modeler has come a long way and is now very well suited to recordings and live play.

Only a guess as the riff makes them all sound the same..
A=USB, B=Digital, C=Analogue

A better test with sustain, fade and hard hits is needed. ;) imho

You guys are talking about “dispelling the myths”. Sorry, but how can you do that when the listening material is MP3? MP3 may sound like your average CD on a low quaility audio setup, but I can clearly hear the difference of MP3s on a setup of a Rotel Stereo Budget Pre-Amp and a pair of Musikelektronik Geithaun RL-904 active-coax (, feeding the pre from a budget notebook (Siemens Amilo-A)

So, what sense does it make to test the way we hear the sound of three recordings after the way we hear the recordings already has been defined by a 5:1 psychoaccoustic compressor.

Afar from that, I do believe, that analogue equipment is very excellent these days.

BTW: Those speakers are so bloody amazing. I heard them against many of the flagship speakers of the consumer High-End speaker manufacturers and they beat most, except a very few exceptions. Personally I have the RL-906, which is active too but much smaller and cheaper. I use them at home for listening to music. The bass is dry as dust and goes pretty deep for such a small box, voices are, well, can I say original? And positioning is excellent due to the coax. But the very best is their extreme (!) musicality. I know guys who sold their electrostats because of these. Very fast speakers. Well, just wanted to make you know.

P.S. Why not re-test, this time with FLAC or APE samples? Those can be converted to WAV loselessley. I would be very interested in that.

It’s more like 10:1 psycho-acoustic compression. Mp3 is the most widely used format for digital music distribution. It is only going to get more prevalent. The test is not to tell if you can hear a difference in a scientific listening environment (such as your own). The test is to hear if the people downloading and listening to your music will ever know the difference. If you can hear the difference and are making music only for your own listening pleasure, then by all means, do whatever you need to do to feel good about your expensive equipment. If you are making music for people to listen to then there is no sense killing yourself over that final 0.02% quality difference.

I will post up the uncompressed .wav sound samples as well (soon). Trust me, there isn’t really any more difference there than here.

I think the reason people rip on Line6 and other modelers (but especially Line6) is that thier copy writing and manual writing departments give the impression you will plug in and sound exactly like Jimmy Page on Album X, track Y. They leave out the part that following the mic model has to be all the same studio processing to get to the “famous sound”.

I once walked through a Line6 manual and started listing each place where the manual alluded that the model sounded like some famous track. I stopped at 36 such hits.

The reason people rip on it is… the marketing department built unrealistic expectations.

FLMason: I think the reason people rip on Line6 and other modelers (but especially Line6) is that thier copy writing and manual writing departments give the impression you will plug in and sound exactly like Jimmy Page on Album X, track Y.

Well, I don’t really think it’s hype per se. You REALLY CAN sound exactly like Jimmy Page with a modeler. there’s just one CRUCIAL factor they fail to mention. You have to be able to PLAY as well as Jimmy Page too…which is where most of the noobs who buy their gear fall woefully short. All one has to do is get on YouTube and listen to some of the impressive stuff people have recorded through Line 6 gear…such as the following…

…recorded using a Flextone III XL.

Just a cursory listen to the many recordings made with Line 6 gear will be enough to prove to anyone that it’s possible to sound like *insert your favorite guitarist* using their processors. You just gotta have the talent to go with the gear.

A analog sounds , between B and C couldnt destinguesh between spdif and usb, but it had a very slight harshness. My ears are sensitive when it comes to mids and highs.
heard the difference thru my Slogic HFI 550 headphones.

For the average listener it wont matter at all, so yeah I get your point.

Its all about the customer and they dont listen thru studio monitors with trained ears, so small differences really don’t matter to them.

Keep Up the good work!

I just stumbled on this. I know you did this test a while ago, but it should be mentioned that the USB and SPDIF outputs probably create a bit-for-bit identical waveform, as long as the sampling rate and bit depth is the same.

In other words, there is not only no audible difference, there is no difference between them period.

So it is more instructive to ask how many people correctly identified A as analogue, regardless of whether they pretended to hear a difference between B and C.

But all seriousness aside, I agree with your main point that the difference here doesn’t really matter (especially on the average user’s speakers).

That is an excellent point and you are certainly correct on all counts. When I first created the audio files for the test I expected that and a bit-by-bit comparison of the files revealed that they were identical.

My interest in this test was more about what sounds best than what is technically best. I chose B to be best sounding as it has the most dynamic impact. This is most easily heard in the beginning of clips. The differences are really small and basicly non-existent but still this slight difference I percieved would make to use S/PDIF with the tested combination. Change the soundcard and result might be different.

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