TC Electronic Powercore Firewire

Photo: Mark Ewing

TC's plug-in powerhouse is now available as an external, Firewire-connected rack unit.

TC's existing Powercore PCI card has been a popular choice for both Mac and PC users looking to augment their computer's own processing power with additional DSP. The key to its success is that its high-quality, DSP-powered plug-ins place minimal drain on the host computer, yet as far as the user is concerned, they look and behave like any other VST-style host-based plug-in.

The PCI card is supplied with a number of extremely good-quality plug-ins, most notably two different reverbs, one based on algorithms taken from TC hardware and the other a new algorithm that blends elements of the TC sound with 'classic' characteristics that are reminiscent of older Lexicon reverb processors. While some host-based reverbs can be quite impressive, the restrictions on available CPU power means they can never be as sophisticated as reverbs that run on their own DSP chips, and once you've heard the difference in quality, there's no going back. The other bundled plug-ins cover modulated delay, EQ, dynamics, multi-band dynamics and a voice channel (Voice Strip) with five processing stages. Additional plug-ins are available from both TC and third-party companies to extend the capabilities of the Powercore.

Going Mobile

Unfortunately, the PCI card format is incompatible with the majority of laptop computers and also with 'slotless' Apple iMacs, and given the increase in both power and screen size offered by these types of machines (not to mention low physical noise in the case of laptops and the G4 iMac), they are particularly attractive to musicians. To address this issue, TC have developed a Firewire version of Powercore built into a 1U hardware rack, and though it costs around 50 percent more than the PCI version, it has approximately 50 percent more processing power, allowing more Powercore plug-ins to be run simultaneously. Powercore Firewire currently runs under version 1.7 of the Powercore operating software, which may also be used with existing PCI Powercore cards to provided full OS X support with Audio Units compatibility.

Powercore's MegaReverb plug-in.Photo: Mark EwingInside the 1U case are four Motorola 56367 DSP chips, each with 512 kilowords of SRAM and running at 150MHz, a 266MHz Motorola 8245 Power PC chip and 8MB of on-board SDRAM. Three Firewire connectors are fitted to the rear panel for connection to the host computer and to facilitate the connection of other Firewire devices or additional Powercore units, and power for the unit comes from an in-line adaptor. A blue Powercore logo on the front panel completes the picture and prevents the otherwise plain box from being visually boring. However, the blue logo is not merely for show as it begins to pulse during boot-up and will also flash once to indicate that a plug-in has been loaded. If Powercore crashes for any reason, the blue logo goes out.

As well as working within Mac-based VST environments, TC have now included support for the new Apple Audio Units (AU) format via an inbuilt wrapper program. There's no direct support for RTAS or MAS formats, although the latter may become less important as MOTU are apparently planning to implement Audio Units support in Digital Performer soon. The Audio Units wrapper program is also designed to handle third-party Powercore plug-ins such as those available from Waldorf, D-Sound and Sony. It is important to reiterate that all Powercore plug-ins must be specially written to run on the Powercore DSP platform, so you can't use Powercore to run your existing host-based plug-ins. However, by using Powercore to supply high-quality EQ, dynamics and reverb (as well as a number of third-party and optional TC plug-ins), you can free up the maximum amount of your host CPU power for your favourite software instrument plug-ins. The same bundled set of plug-ins comes with Powercore PCI and Powercore Firewire. Internet connection is necessary for authorisation when installing optional plug-ins, though no authorisation is needed for the bundled plug-ins.

Both Mac and PC platforms are supported, though Mac users need OS 10.2.4 as a minimum requirement, whereas Powercore PCI will run under Mac OS 9. On Windows, Powercore may be used in Direct X applications such as Sonar by using a suitable wrapper program, such as Cakewalk's VST-DX Adapter.

Plug-in Bundle

The bundled plug-ins comprise Mega Reverb and Classicverb, Chorus/Delay, an enhanced version of EQ Sat, Voice Strip, Powercore CL, 24/7·C Limiting Amplifier and Master X3, a multi-band mastering dynamics processor based on the Finalizer algorithms and providing compression, expansion, limiting and dithering. You also get the Powercore 01 monosynth on the install disc, which was previously available as a free download. The compressors are available in mono and stereo versions for compatibility with existing sessions, and in new projects, the plug-ins automatically insert as mono or stereo depending on whether the audio channel is mono or stereo.

ClassicVerb is the jewel in the Powercore crown.Photo: Mark EwingFor me, Classicverb is the jewel in the Powercore crown, offering 16 reverb algorithms encompassing the usual plates, halls, rooms and cathedrals as well as a spring and a long-decay-time FX setting. Modulation is provided which works inside the algorithms to help randomise the reflections (rather like Lexicon's proprietary Spin and Wander parameters), where the user has control over speed and depth. Tonality can be adjusted using the high and low Colour controls plus a variable-frequency high-cut filter, and of course there's a dry/wet balance control. The remaining controls are very simple, and adjustments can be made in the graphical decay window by dragging handles with the mouse, or the values may be changed directly using up/down arrows. The main variables are restricted to pre-delay, decay time, pre-gain and decay gain, though there's also a choice of reverb styles as well as modulation speed and depth adjustment.

By contrast, Mega Reverb is based around the Core 1 and 2 algorithms taken from the TC Electronic M5000 and features an enhanced reverb tail design. The user interface makes good use of graphics for easy setup, including a choice of room shapes. The decay time can be adjusted in three frequency bands, the crossover points of which may also be set by the user. Mega Reverb is more of a room simulator than Classicverb and its well-rounded, lifelike character provides a welcome contrast to Classicverb.

EQ Sat is designed as a mastering-quality EQ using the same algorithm as the Finalizer. It has a stereo signal path, now with low and high shelving bands, plus three bands of fully parametric EQ. A soft saturation function is available to emulate a little analogue warmth. Also based on Finalizer algorithms is Master X3, a multi-band dynamics processor capable of expansion, compression and limiting. Dithering is also included for bit-depth reduction. The interaction between the bands can be adjusted by applying what TC call Target Factors to reduce the number of parameters requiring user adjustment. Soft clipping is also available, again to help capture that analogue character.

Chorus Delay is based on the TC Electronic 1210 Spatial Expander.Photo: Mark EwingThe 24/7·C compressor/limiter appears to be modelled after the classic UREI 1176, and can be used to provide compression or limiting for mixing and mastering. Both the sound and user interface (including the counter-intuitive direction of the controls) of the original are closely modelled, and increasing the input drives the limiter harder according to the selected ratio. As with the original, you can jam down all four Ratio buttons at once by holding down the shift key as you click on them! One concession to the 21st century is the addition of auto-gain sensing, which adjusts the output depending on the program material.

Chorus Delay is based on the TC Electronic 1210 Spatial Expander and is dedicated to creating modulated delay effects such as chorus, flange and slap delay. It can also create more conventional echo effects with variable feedback. Again, a neatly designed graphical interface makes it very easy to use while a BPM-delay time scale has been added to make setting tempo-related delays easier.

Powercore CL behaves like a good analogue compressor and is designed for general-purpose dynamics processing. It offers all the standard compressor parameters, sounds musical and doesn't do anything unpredictable. Voice Strip also offers compression, but is built to operate much like a hardware voice channel, except of course it has no mic preamps. The processing stages comprise compression, de-essing, EQ, low-cut filter and a gate. The compressor algorithm is optimised for vocal use, as are the EQ ranges. Powercore 01 emulates the Roland SH101 monosynth, both audibly and visually. It is good for cutting lead sounds and fat basses and, as far as I can remember, sounds pretty much like the original.

Optional plug-ins include TC's own Master X5 five-band dynamics processor and the Assimilator 'fingerprint equaliser', and later in the year TC/Helicon will be adding Voice Modeler, which can be used to change or improve the character of a voice. Sony have developed the Oxford EQ and Inflator plug-ins, while Waldorf have the D-Coder and D-Sound have tube emulation.

Performance Issues

Photo: Mark EwingThe latency penalty of using Powercore is related to the buffer size set up in the host program, so if one plug-in is used in each signal path, the latency will double compared to using only host-based plug-ins. There is also a further proportional increase for every Powercore plug-in stacked in series, but given that most host software can achieve extremely low latencies when used with the right hardware, this increase should not impose a serious limitation. However, it can be problematic when using host software that doesn't include inbuilt plug-in delay compensation, so the bundled plug-ins also include a delay compensation module for those users whose host programs don't look after this automatically. According to TC Works, PC users actually have an advantage, as they tell us Firewire communication is handled more efficiently by the PC architecture.

The larger the audio buffer size, the lower the loading on the CPU of the host computer, but of course larger buffers mean higher latencies. High latencies are no problem when mixing but are intrusive when recording, especially where virtual instruments are involved. The minimum I/O buffer size for Powercore to work properly is 128 samples, but it is optimised for 1024-sample buffer sizes. Unless you're really pushing the limit of your system as regards plug-in usage, the lower buffer sizes seem to work perfectly reliably. Apparently If you find that you have an high CPU load when using Powercore plug-ins within Logic under OS X, you can go to Logic's Audio menu, select Audio Hardware and Drivers, and then set Process Buffer Range to 'small' or 'medium', as the larger the setting, the greater the CPU load. If you are running on a multi-processing Macintosh, setting the ADMA buffer to a value of 2 in the control panel is also said to help gain a small performance boost.

Voice Strip.Photo: Mark EwingPowercore also includes a No Latency mode that works by modifying the way Powercore communicates with the computer so that data is sent directly rather than in blocks. This is enabled by clicking on the Powercore logo at the bottom of the plug-in window, which will light up red. Before you ask why such a useful feature isn't always active, the answer is that it hogs power from your onboard CPU (by my estimate it slightly more than doubled the CPU loading), but it is useful to turn it on when you're playing a Powercore software instrument in real time or monitoring an overdub with a live effect. The time you need most plug-ins is when you're mixing, where higher latency is of no consequence.

Powercore's hardware and all the included Powercore plug-ins support 96kHz processing, though the higher the sample rate, the greater the DSP overhead. As a rule, if you double the sample rate, you halve the number of plug-ins you can run. During my tests (at 44.1kHz), I had five reverbs running in a track along with a couple of limiters, a chorus and a channel strip and the control panel showed I was using around half of the Powercore's available processing power and much less than half its memory.

Testing

The Powercore software installed automatically onto my Mac G4 running OS 10.2.6, though it rightly refuses to install if operating systems earlier than 10.2.4 are being used. Any problems experienced with the beta version of software I started out with vanished when the release version 1.7 was shipped to me and the system ran just as smoothly as my PCI Powercore card.

Photo: Mark EwingTesting with Logic Audio Platinum, I found that as soon as I inserted a single Powercore reverb, Logic's performance meter showed around 15 percent CPU loading, but this didn't increase significantly as further plug-ins were loaded. TC are still working to get the CPU overhead down further, but of course I have to review what's available now. Powercore 01 used not to work in Logic because of MIDI routing issues, but as Powercore's AU support includes full MIDI compatibility, it now works fine. It's a gritty little monosynth reminiscent of simple instruments such as the Roland SH101, and only takes around a quarter of a DSP chip to run.

To The Core

The Powercore Firewire provides 50 percent more processing power than its PCI cousin.Photo: Mark EwingI'm a huge fan of Powercore and have been using the PCI version in my studio for a long time. In fact it's so good that my hardware reverb units, some of which are fairly upmarket, rarely get used any more. The EQ and compressors are better than average with 24/7 being particularly attractive to vintage gear fans, while having the EQ and dynamics from a Finalizer means that you can tackle most mastering jobs in the knowledge that you are working with competent tools. Of course all TC's own Powercore plug-ins work on the Firewire model but it always pays to check that any third-party Powercore plug-ins you're planning to buy are also compatible with the Firewire version.

Operationally, Powercore Firewire behaves much the same as its PCI sibling, the main difference being that on the Mac it only works under OS 10.2.4 and above (though it's too early to say if it works with the just-announced OS 10.3) with no OS 9 support at all. The same plug-in bundle is provided with each and the quality of the plug-ins is impressive, especially the reverbs. The real benefit of the Firewire version, other than its increased horsepower, is that it works with laptops and iMacs, enabling what is ostensibly a budget computer to be used as the heart of a very serious recording system without having to compromise on effects. As I've said before, it's almost worth buying Powercore just for the reverbs — and the flashy blue light of course.