Thread: MOTU conversion/audio quality vs APOGEE & RME

Originally Posted by bigtree

"re: I've done that a lot, you aren't alone."

What I meant was: I've often thought my mix was going to to sound completely different using something new or changing some method and its ended up sounding so close. Does this happen to you? Its a slow process to re-curve listening habits for me.

Big time. I go back and listen to old mixes thinking I must be 1000x better now and lo and behold there is improvement but not nearly what I thought. I REALLY revamped my studio this year going from "busting at the seams" with gear to "recording in a third world country". I basically sold everything that didn't blow me away and now I have the studio that fits me perfectly. This started in October and ended last week. I had about a month were other then my 2 buss(which is sacred, until I find something better:-) I only had one outboard compressor and I was used to having 8 channels of compression. I sold all but 2 API pre's and was relying on my console pre's. During this time I've tracked and mixed about 100 songs. As there is quite a time lag of tracking to mixing in most projects I had the experience of mixing through my console using mostly ITB plugs on tracks that were recorded with ultra high end classic gear like KM84's, distressors, shadow hills stuff etc. I also mixed tracks that were recorded on next to nothing gear wise(like SM57's on overheads instead of KM84's) and mixed mostly with ITB processing but still used my console for eq. Third I also am currently mixing stuff recorded on next to nothing gear wise but I have boat loads of gear again.

This was an awesome personal experiment. In all three of these instances I can't which is which because I am a bigger influence then the gear. I hate it when people say the gear doesn't matter because it does but when you've worked on the best it is easier to pull out great sounds out of nothing. I'm not saying I'm an amazing engineer. I am solid (one of these days I'll post something). I was astonished that there wasn't a major drop in quality. When I realized there wasn't I pulled out a new philosophy. When I would notice that I would consistently take too much time on something I would by a piece of gear to get me where I need to go quicker. I'd always get there but in this business you need to be quick as well. For example I noticed I was spending as much as 20-30 minutes on room mic's to get my snare were I wanted it. I found a piece of gear that gets me there in usually 2-7min now(docderr module). Now I am pulling out complex mixes like the ones I am doing for a big band with drums, horns, keys, 2 guitars, slide guitar and loads of back-ups in about 6 hours top to bottom. A standard rock mix is about 3-4 and a half hours. With the studio as busy as it is I need to mix a song everyday 7 days a week just to keep up. Of course some days I'll mix 2 or 3.

Sorry for the long drawn out answer.
Paul

Originally Posted by sdelsolray

I've used many different converters. A smaller group are converters that I have actually owned and used extensively. They are:

Digi001
Digi003
RME ADI Pro
Lucid AD2496 and DA2496
Lucid 88192
Lavry Blue

I only record solo finger style acoustic and classical guitar, recording and mixing only 2 to 4 channels, so perhaps the converters are not as critical in my application. In any Event, I do not hear much of a difference with different converters. Indeed, with ABX and null tests I did, there usually wasn't much of a difference at all.

For example, when choosing between the Lavry Blue and Lucid 88192, I thought I could hear a difference, but I'm never sure about such things, particularly when they sound virtually the same to begin with. Confirmation bias can easily come into play. The ABX and null testing I did confirmed that the difference was minuscule, sometimes not there at all. More importantly, as far as my listening went, one did not sound better than the other, just two (very slightly) different flavors of very nice. I sold the Lavrys and kept the Lucid. I am happy camper with the Lucid 88192. They function very well indeed, are built like a tank and are very reasonably priced.

Originally Posted by bigtree

sdelsolray, thanks for chiming in.

Fun topic.

How can a null test tell you they all sound close though? I don't get that at all.
I do believe you all don't hear enough of a difference, but not being able to pick the Lavry Blue's out of those is astonishing. Its so apparent to me.

I had to research the Lucid vs Lavry and found only one reference: http://www.gearslutz.com/board/gear-...d-88192-a.html I never trust shootouts but still read and think about it all.

I'm obviously shooting for that extra slice of the pie. I definitely agree quality mics and pre's show the most noticeable difference up front but cannot deny the subtle differences I hear are bigger than meets the eye.

Curious,

Do external clocks make an even greater improvement?

I'll explain what I did. I used one Gefell M295 mic into a Pendulum MDP-1a preamp. That preamp has two identical balanced outputs per channel. I ran one output to the Lavry Blue AD and the other to the Lucid 88192 AD. On each track I recorded a test tone first to eventually set levels. I also nudged one of the tracks to compensate for the slightly different latency between the Lavry and Lucid. Each converter ran AES/EBU to a SPDIF transformer coupled converter cable to SPDIF on my Digi003 dongle. I reversed the polarity of one track and listened to them together. They did not completely null, but what was left was only some high frequencies about -60dB down from nominal RMS level of the two tracks without reversing the polarity of one track (slightly above the noise floor). In other words, nearly inaudible when compared to listening to both tracks without a polarity reversal on one of them. I ABX'd the pair and I failed miserably (4-6 out of 10 correct on average).

To analyze clocking issues, I repeated the test procedure using various clocks - the Lucid as master via word clock, the Lavry as master via word clock and the Digi003 as master via SPDIF. Although the performance/takes were different for each of these tests, the resulting null tests were basically the same as far as I could tell. Each did not null perfectly but nonetheless only a bit of high frequency info was present down about -60dB from nominal.

I also repeated the listening portion of these tests using 4 different DA converters I had at that time - Digi003, Lavry Blue, Lucid AD9624 and Lucid 88192, multiplied by different clocking variations. Although I thought I could hear distinctions, the ABX testing put me in my place and demonstrated I could not tell a difference.

I listened through active Quested monitors and AKG 240DF headphones.

Dunno about the external vs. internal clock issue. Dan Lavry makes a strong (albeit quite technical) argument that decent external clocks are never better than decent internal clocks but at best are equal.

Although somewhat anecdotal, I conclude that for my uses, and to my ears, conversion is not much of an issue when dealing with modern converters. Much more important are player, instrument, engineer, room, mic, and preamp, in that order (more or less).

Brad from Lavry was kind enough to allow me to post this .

Regarding "Null testing"-

Basically; null tests are useful to determine if two files are identical. If they are different; you hear only the difference.

For those unfamiliar with the term; this test is to determine whether or not two digital recordings (files) are identical. In order to make a meaningful comparison, any potential difference must be addressed so that when the two files are added (mixed) "out-of-phase" they cancel each other, and the difference is silence. This requires the files to contain exactly the same audio content, for the files to be sample-accurate with each other, and for the level to match very exactly.

Typically, the files are placed on two separate tracks and one of the two tracks is moved in the timeline to align the waveforms to a sample-accurate position. The polarity of one track is inverted so the audio content of the two tracks are "out-of-phase" with each other. If there is any difference in the level, the digital level control can be used to minimize this; but unless the difference is zero or exactly equal to the step-size of the digital level control; there will be a small level difference. This would cause two files that are identical in every other way to not cancel out completely.

The usefulness of a null test is extremely limited in determining the difference from the "ideal" as, for example; if either file is "brighter" than the other (has more treble), the difference will be very bright. It is not possible to determine which of the two is brighter by simply listening to the difference; or whether one has more low treble and the other has more high treble and the audible effect is a combination of the two. This applies to ALL differences, including distortion. If one file had only even-order harmonic distortion and the other contained only odd-order harmonic distortion, the null test result would contain both even and odd order harmonic distortion and there would be no way to determine which file contained what distortion simply by listening to the null test result.

So, like many tests; the null test tells you exactly one thing and the results need to be interpreted accordingly. The main reason I used a null test in the past was to determine whether the CD plant had done processing to the Mastered file I sent before manufacturing the CD. In this case; the only important thing was whether or not there was ANY difference. If there was; I knew that something had changed and would contact the plant to arrange to have it re-done. In this case; it did not matter what the difference was (or how it sounded).

The only other application was to determine if the files remained in time with each other. This can be useful if there is a chance that either an edit or a digital "glitch" caused some of the original file to be missing from the copy. In this case; even if there was an audible difference caused by something like AD and DA conversion, it would remain constant unless there was an edit or missing samples. At the point where the change occurred; the "difference" output would suddenly increase in volume because the two waveforms were no longer close enough in content for phase cancellation to "null" most of the signal.

Brad Johnson
Lavry Engineering, Inc.

This topic has been posted as a Sticky:
Null Testing

I don't consider myself a converter expert by any means. However, I have used Motu, M-Audio, RME, Mackie Onyx, Lynx Aurora and others. You should be able to get really good results with any of them. I have gotten recordings and mixes with all of them that I am happy with. In my experience while there are differences, but they are certainly not "night and day" differences. An old Midiman Flying Cow 2 channel converter I think sounds better than their M-Audio Delta converters or a Mackie Onyx every time. RME sounds better than MOTU....but I would say the Lynx sounds best of all these that I have mentioned. Worth the money? I would say yes, but I would personally put mics, preamps, monitors higher on my priority list than converter differences.

I recently swapped out Motu interfaces for Echo Audiofire 12's and the difference was more than noticeable. The imaging and clarity improvement was staggering, noise was reduced and clocking has also improved. Sorry but it is just so obvious to your ears it's not funny, unless of course you have suffered substantial hearing damage, in which case you should not be behind the console anyway. Motu Gear is not terrible sounding overall but it is certainly not in the same league as Echo, Apogee or Lynx stuff. RME is not too bad either.

Some of those differences you are hearing could be due to differences in impedance matching & gain staging. And that would create an audible difference in what one might think is just the converters. You are dealing with differently designed analog input and output electronics. So it isn't really fair in saying one is actually better than another. Most of the signature sound you get comes from your technique of recording & mixing. I feel that way and so does rocksure. A good recording transcends any converter. Tonal quality may be different between units but only you can decide what kind of sound works out best for your technique. Every situation is different and everything offers different tonal coloration. Best is a relative and subjective term. For instance, what do you consider better or best, API vs. Neve, Neve vs. API? They're both fabulous. They both sound incredible. They both have similar advantages. They both sound different. They both sound different also merrily through different gain staging techniques in how you are running them. In my book, both are considered best for my purposes. I have no need, and no desire nor intentions to try anything differently than that. If I wanted a different sound than what my ALESIS HD 24 XR gives me, I might opt for the MOTU 2408? And that's also provided I may utilize a combination of both sets of different converters and analog input/output. I could do identical mixes both ways and choose which one I think sounds " better ". And there is nothing keeping you from doing that. In fact I recommend it. How else are you going to go for your ultimate sound unless you experiment a little?

Variety is the spice of sound
Mx. Remy Ann David

Seems the majority of people tend to believe that there is a different levels of conversion quality, but then some believe that the human ear cannot detect it if there even is one.
The guys over at sound on sound said that unless you have really really great state of the art monitor speakers and a great room that you wouldn't hear a difference
between a Motu converter and a Lynx or such.
I really would like to be able to save the $1000+ by going with an Motu828 instead of RME UFX but only if I'm completely confident that the Motu would sound just as good as the RME.