Portable hardware DSP devices allow mobile producers to tap into the audio processing power once reserved for high-end desktop systems.
One of the key differences between DSP-equipped computer audio platforms such as Pro Tools and "native" systems just about everything else is the burden audio recording and mixing puts on the computer's central processing unit (CPU). Pro Tools HD systems (but not Pro Tools Le and M-Powered, which are native) include digital-signal-processor cards dedicated to running audio effects. By doing most of the heavy lifting, these DSP cards allow the user to manage resources and offer more consistent performance than native systems, which process all audio with the same chip that's in charge of email, hard drive operation, and so on.
On the other hand, native systems work with just about any hardware, can run on systems ranging from high-powered audio machines to laptops, allow you to choose yout audio interfaces depending on the task at hand, and tend to be more affordable than their DSP counterparts. However, folks using native software know all to well what happens when you overload that poor CPU by running more effects and instruments than it can handle distorted recordings, sputtering playback and sometimes devastating crashes. Yes, computers have gotten faster, but the software has also become more demanding, and even blazing machines have been known to hang due to CPU overload.
Powered plug-ins bridge the gap between DSP and native systems. By mating a hardware unit with a collection of effects (and sometimes instruments) designed to run on it, products such as T.C. Electronic's PowerCore, Universal Audio's UAD and Solid State Logic's Duende work within a software host in the same way as a typical "native" plug-in, while offering the performance boost of a DSP engine.
All three of these systems are available in a number of different physical formats, including PCI and PCIe expansion cards designed for desktop computers. But there are also options for mobile production, using either FireWire (PowerCore and Duende) or a laptop's Cardbus expansion slot (UAD), literally putting power once reserved for the studio in a package that can go anywhere.
Plugging-in
Setting up a system of powered plug-ins is a little more complicated than installing standard effects and instruments. It's a two-stage process: First the hardware is added to the computer; then the plug-ins are loaded.
If you have experience installing hardware such an external audio interface, you know the drill; before you start, you should check the manufacturer's website and get the latest drivers for the hardware, as well as the most recent update of the effects. Sometimes, there's an additional update that configures the hardware with the latest firmware. The good news is that major upgrades to the software
don't necessarily require new hardware, so unlike some computers the DSP device can remain useful years after purchase.
Only after the hardware is installed and updated will you add the plug-ins. The installers take care of the rest, simultaneously installing multiple versions of the plug-ins so that they can run with all of your music software. A few years ago, the benefit of powered plug-ins was limited to those using multiapplication formats (such as Core Audio and VST). Today, you can also use them with Pro Tools-family DAWs via a slick Fxpansion (fxpansion.com)"wrapper" program that allows Core Audio and VST plug-ins to run under RTAS.
Once installed, powered plug-ins appear in your DAW exactly the same way as other effects and instruments, and you load them into track and bus inserts just like their non- DSP counterparts. However, the plug-ins themselves won't run unless the hardware is attached and is recognized as available by the host software.
This is one area where FireWire devices are at a bit of a disadvantage: Yes, they can work with a wide range of computers, including both notebook and desktop models. But they also require power (the Duende can sometimes run on bus power provided by the computer) and if you're jostle the computer too much, the FireWire connection can drop. Sometimes, even a slight movement of the cable within the jack can cause the computer and device to lose communication. The ExpressCard option requires no power and stays in place when you move the computer but it can't be used with a desktop machine.
Powered plug-ins can run on the same channel strip as standard plug-ins, so you can, for instance, combine a Waves EQ running natively with an SSL dynamics processor running through the Duende. If you havemultiple DSP devices (for example, both a PowerCore and a UAD-2 Solo), effects from both can be used on the same channel with no conflict.
However, these hardware devices do introduce some latecy into the system. Depending on the host software, this can cause audible delay, especially when you're recording on a channel featuring a powered plug-in, unless you configure the hardware and software carefully.
The overall number and complexity of the effects you can run varies depending on the DSP chips housed in the hardware you're using, as well as the sample rate of your project. Higher end devices, such as TC Electronic's PowerCore 6000 (a FireWire rack unit based on the company's standalone System 6000 processor) have multiple DSP chips for extremely robust performance. But the latest compact devices are no slouches. The UAD-2 Solo, for example, can run seven stereo instances of the complex Dream Verb and as many as 51 mono instances of the Neve 1073SE channel strip. The Duende Compact can run up to 16 channels of DSP.
While the performance boost is nice, ultimately what makes powered plug-ins compelling is the quality of the effects that run on the hardware. Each of the devices we tested had its own sonic "personality."
The Duende's mission is to bring big-console SSL sound to computer users. So while the effects don't emulate hardware by other manufacturers, the effects you get are outstanding. In a way, the lack of choice makes using the Duende very efficient. You don't spend a lot of time trying to decide between, say, Pultec and Neve EQ plug-in.
However, if you're interested in emulations of a huge array of vintage gear, the UAD family has you covered. It comes standard with the Mix Essentials II bundle which includes UREI, and Pultec emulations, the DreamVerb reverb, and the CS-1 channel strip, plus a $50 voucher towards the cost of additional plugins from the Universal's library. This includes effects based hardware by Neve, Moog, Roland, EMT, Fairchild, and others. Version 5.4 of the software boasts a new Emperical Labs FATSO analog tape-simulator plug-in that lives up to its name.
The Powercore collection also boasts a number of vintage-style effects, but at its heart are T.C Electronic algorithms, such as MegaReverb, Chorus/Delay, and mastering effects from the company's Finalizer series. The bundled collection is augmented by an array of optional plug-ins including harmony and pitch correction effects ported over from TC-Helicon hardware.
All three of these systems offer outstanding sound, and a substantial performance boost over purely native plug-ins, especially on a laptop. Once you power up your plugins, you may never want to go "native" again.