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Spirit Protracker

8-channel Mixer By Paul White
Published July 1995

Paul White goes live recording armed with just an 8‑track recorder and Spirit by Soundcraft's new ProTracker.

Spirit by Soundcraft's tiny ProTracker mixer may not look much like a conventional desk — but that's because it isn't one. This little mixer has a number of possible applications, but I'm going to concentrate on its live recording abilities (see the 'Going Live' panel elsewhere in this article), where it may be used to get mic or line signals onto tape cleanly, while at the same time providing a basic monitor mix.

The ProTracker can essentially be viewed as eight mic/line DI boxes sharing a box with an 8:2 monitor mixer. Because signal levels are notoriously inconsistent in live situations, the ProTracker also incorporates a safety limiter which can be switched in or out for any channel, and which is set from a master threshold control. Individually switchable phantom power is available on all the mic inputs, and all the tape inputs and outputs are balanced, but there's also a lot that's not available — there's no EQ at all (though there is a high‑pass 100Hz filter), there's only one Aux Send, and there are no dedicated subgrouping facilities. Essentially, the ProTracker will help you make a good recording, but unless you can make do with the most basic of mixing facilities, you'll need a more conventional mixer at the final mixing stage.


The ProTracker comes as a mains‑powered, 3U rack unit with all the connections, other than the headphone jack, on the rear panel. Each of the eight input channels is comprised of a mic/line input with the aforementioned switchable 100Hz high‑pass filter, and phantom power may be fed to the inputs via individual switches on the rear panel. The line input is balanced, and another rear panel switch sets the sensitivity of the tape In/Outs to either ‑10dBV or +4dBu, while the Gain is set by means of a rotary control. To round off, there's a (globally switchable) pre/post‑fade aux send, and an insert point that can be separately switched into either the input or monitor path.

Each of the tape outs is routed via a limiter which may be switched in independently for each channel. The limiter threshold is set globally using a 7‑position stepped switch in the master section of the mixer, and though the lowest setting is +12dB, this seems to corresponds nicely to the maximum input level on an ADAT. It may not be appreciated that digital multitracks are usually calibrated so that a nominal 0dB input still leaves a reasonable amount of safety headroom. When using an ADAT here, a 0dB input seemed to register at around ‑10 to ‑12dB on the ADAT's own meters. The ProTracker's limiter has a reasonably fast 300 microsecond attack time, and if the signal is deliberately pushed into regular heavy limiting, the audible side effects are nice enough to be useful as an effect. A yellow LED shows when a channel is limiting, and a second red LED warns when the mixer input level is within 4dB of causing the internal circuitry to clip.

No recording mixer would be complete without a Pre Fade Listen button (PFL), and in the case of the ProTracker, this works as you'd expect, both for soloing the channel and putting up the signal level on the master meters.

Tiny though the ProTracker is, the channel layout follows an in‑line topography, the monitor section simply comprising a short fader and a pan control. As mentioned when discussing the input section of the channel, the aux send and insert point can be placed in either signal path.

Master Section

The ProTracker may be small, but it still needs a master section, and it's while exploring this area that you realise how clever this little mixer really is. Here you'll find the Aux Master knob and Pre/Post switch, as well as a fader to handle the stereo return (which also has its own PFL button), but there are a couple of less obvious buttons that require explanation. Mix to 7/8 takes the stereo output mix and feeds it through input channels 7 and 8 instead of the usual channel mic/line inputs. This can be used for a number of applications, including recording the entire mix onto two tracks of an 8‑track while still recording the first six channels onto separate tracks. Because this kind of routing could easily result in a feedback loop, the feed from the tape returns on channels 7 and 8 is disconnected in this mode.

The other neat switch is labelled Input to Mix, and allows the mic/line inputs to be fed directly into the stereo mix; the tape returns are bypassed in this mode, although the tape sends work as normal. Used with the Mix 7/8 switch, the input signals can be sent to the mix while the tape returns are still mixed to channels 7 and 8. If you're stretched, this makes it possible for the desk to be used to mix a gig at the same time as recording it!

The Mix L/R faders have yellow caps and control the Mix Out level; the signal is available on both balanced XLRs and unbalanced phonos simultaneously, as are the 2‑Track Returns. A separate pair of jacks carry the Left/Right monitor outputs, though plugging in a pair of headphones will mute these. Simple 8‑section LED meters monitor the mix level or the PFL level, and the headphone outlet is switchable to monitor the 2‑Track Returns, the Aux send, Channel 7/8, or the whole stereo mix. A separate headphone level control is provided, and when a channel is PFL'd, its signal overrides the current headphone monitor selection. That leaves only the limiter switch, which may be set in 2dB increments between +12 and +24dB.

If you need more channels, a pair of 9‑way 'D' connectors on the rear panel allows virtually any number of ProTrackers to be used together — so 16‑ or 24‑track recording isn't out of the question.


The ProTracker's strength is its simplicity — not only is it easy to use, it also has a very short signal path, and this results in very little coloration of the recorded sound. Working with an 8‑track recorder, where you want to record one signal or mic per track, the ProTracker is ideal, but it does fall down in one area in comparison to conventional mixers — with only eight channels at your disposal, you can't route complex subgroups to tape. This isn't too serious when you only have eight tape tracks to play with, but if you double up to create a 16‑track system, I feel you might find the routing options a little too limited. Similarly, the lack of EQ means that you can't do much with the sounds other than limit them or connect processors via insert points, and while this is absolutely fine at the recording stage, it leaves a lot to be desired if you have to do your final mix on the ProTracker.

I see the ProTracker mainly as a 'record‑only' mixer, and in this light, it performs brilliantly. The sound quality is exemplary, the limiter is a real life‑saver, and the fact that the mixer is only 3U deep means you could flightcase your entire mobile studio and still be able to carry it with one hand. If you want to work with 16 tracks (or even more), and you don't need fancy subgrouping, just link two or more ProTrackers together.

I'll finish as I started, by saying that the ProTracker concept is really based around eight mic/line DI boxes with limiting and phantom power combined with a simple 8:2 monitor mixer. When you add up the cost of buying all these bits as discrete components, the ProTracker makes a lot of financial sense — and it also reduces the live recording wiring nightmare to a bare minimum. OK, so it can't tackle every conceivable job, but in the majority of situations, it's all you need. A great idea — and something that I see myself using on a regular basis.

Going Live: The Protracker In Use

The only way to evaluate a mixer like this is to use it, so I volunteered to make a live recording of a local rock band at their rehearsal room. The idea was to use one ADAT to record the main backing tracks via ProTracker, then to bring the project into my studio, where a second ADAT could be used to overdub the vocals and obligatory guitar solos.

I set up a couple of dynamic mics close to the guitar cabs, fed the bass into the ProTracker via a phantom‑powerable active DI box, and miked the drums with dynamic mics on the bass and snare, and a couple of capacitor mics as overheads. As we were after a fairly live sound, close tom mics weren't used, and as it turned out, the tom level in the overall mix was fine. Using the PFLs to set the individual to‑tape levels, I next switched in all the limiters so that they'd operate just before clipping on the ADAT. A test recording confirmed that everything sounded OK, and that there was adequate separation. I then pressed the Record button and went to hide in the kitchen until they'd finished!

As it turned out, it's a good job I had the ProTracker's limiters at my disposal, because everyone seemed to get louder after the sound check, especially the bass player. The effect of the limiter on the bass produced a really punchy sound, so rather than reset the levels for another take, I left things as they were.

After the session, the phono mix outputs were plugged into the band's hi‑fi, and we listened back to a rough mix of the recording. The band were well pleased — even though we had had no EQ and no effects, it was evident that the recording quality was excellent. At the time of writing, the studio overdubs haven't yet been finished, but I'm already convinced that for conventional band recordings, this hybrid mobile approach is infinitely preferable to having a drum kit and three Marshall stacks set up in your lounge!


  • Excellent sound quality.
  • Compact and simple to use.
  • Good on‑board limiters.
  • Balanced tape feeds with a choice of operating levels.


  • Restricted routing options.


Ideal for those who want to make live recordings with a simple, portable, 'record‑only' mixer, but who have a full‑size mixer at home to finish the job.