I have never accepted digital mixing fully, and have always sent my Pro Tools mixes out to analog line amps and bus compressors to get that undeniable depth, width, punch and realism. Bob Katz, a known authority on such matters, has said that this technique is all that’s needed, and that the need for analog summing is a “red herring.” In other words, all you need to get “that analog sound” is two channels of analog flavor by routing out to some analog gear in stereo. He and many others have insisted that what we mixers like about analog summing is really just the harmonic distortion we pick up by routing out to analog gear. Indeed, I do like that.

However, there are those on the other side of the fence who insist that analog summing is giving them more than just the harmonic distorition. They tend to claim that the stereo field opens up, that the reverb and delays they use are more evident and elegant, that there is a greater depth to the soundstage, and so on. I knew I liked the sound of a console, but I hadn’t really done much to compare digital and analog summing, other than to work in different scenarios and think: “that was different” and “I like the sound of a console.”

Last year I bought a Dangerous Music D-Box, which has an 8 channel summing mixer. I hadn’t used that summing mixer until this week, when I thought it was time to give it a shot. I really wanted to make an apples-to-apples comparison, so here’s how I configured my trial mix: Pro Tools HD -> Lynx Aurora 8-channel D/A converter -> D-Box summing mixer, then the stereo outputs of the D-Box -> Vintech x73i line amp -> API 2500 bus compressor -> Cranesong HEDD 192 A/D converter -> Pro Tools for the print. (Everything is clocked to an Antelope OCX-V).

For the analog summed mix, I stemmed the drums to channels 1-2, the guitars to 3-4, the effects and bells to 5-6, the bass to 7 and the vocals to 8. For the digitally summed mix, I simply bussed everything out to 1-2 and printed a mix. In this way the only difference between the two scenarios is that I summed in analog in one and in digital in the other. I’m still getting the coloration of the D-Box summing amp’s circuitry in both cases.

The digital mix:

Audio clip: Adobe Flash Player (version 9 or above) is required to play this audio clip. Download the latest version here. You also need to have JavaScript enabled in your browser.

The analog version:

Audio clip: Adobe Flash Player (version 9 or above) is required to play this audio clip. Download the latest version here. You also need to have JavaScript enabled in your browser.

Is there a difference? Yes, and my vocabulary is about to sound the same as everyone elses: the analog summed mix is wider, deeper, more musical, more spacious, etc… Especially noticable to my ears is the detail in the effects, the delays and reverbs. They seemed more audible in general, but also more spacious.

In general, the best way I can describe the difference between these two mixes is that the ITB mix sounded like I feel before I do yoga, and the analog summed mix sounded like I feel after yoga – as if some tightness had relaxed and opened up the various elements of my body so that each molecule had that much more space. I know, it’s a pretty lame, new-age analogy, but there it is. Which did I prefer: the analog summed mix, for sure.

I also looked at the waveforms, and they were different, as you can see by comparing Fig 1 and Fig 2. I have no idea how to make any sense of what’s going on in these waveforms, but my sense is that the analog summed waveform is more complex, which fits my understanding of analog gear: it’s vastly more complex and nuanced than digital – just ask any plug-in designer.

If nothing else, this experiment helped me understand that the D-Box’s summing section is worth using, and given the price of that unit its value just shot up considerably as an indespensible centerpiece to my mixing studio. I’m happy to have confirmed my suspicion that analog summing is superior to digital summing. But is it vastly different? – well, not vastly different (it is only 8 channels), but for me it’s all about making small differences at every stage of the mix, such that the cumulative effect is a better, more musical, mix. I don’t ever expect one piece of an elaborate chain to hold the key to the sound. I do yoga every morning becuase it makes my day better, not becuase it makes my day.

I just installed an Antelope Isochorm Digital Clock in my mix room, and it’s an amazing contribution to my system. Anyone could hear the difference. Everything sounds so much more open, punchy, and easy on the ears. In fact, it sounds more analog. I hadn’t thought of this angle when I was writing the review of these clocks for Tape Op (with Jessica Thompson), but it’s true. Someone told me Joel Hamilton said it was like working on tape again, and it just made sense, but I’d say it also is like working on a console becuase it’s so wide and open sounding. But it is like tape in that the harshness is gone – just gone. The top end is smooth and airy, and the bottom is fat and punchy. It’s a vast improvement, and I am thrilled to have this thing ticking away in my rack.

What a clock does is regulate the 0s and 1s streaming at ultra fast rates through the system (a CD streams 44,100 of them per second). When the spacing between these numbers isn’t right, you get distortion – called “jitter” in clock lingo. With a more stable clock, the reduction in jitter allows the sound to open up and carry far fewer of the anomalies we have heard in digital over the years. In my case, the Antelope Clock is feeding both my Lynx Aurora converter, my Cranesong HEDD converter, and my Dangerous Audio D-Box D-A converter that I use for monitoring. When I consider what an impact the Antelope is having on so many aspects of my gear – including how Pro Tools and all the plugins are operating – it’s a no brainer that this is a killer piece of kit for any digital system.