Bornheim, Germany’s Marcus Stahlberg, operating under the Digilogue banner, has been working on a new audio editing platform called Acoustic Cutter, but his earlier foray into the world of digital audio came in the form of a suite of 10 DirectX/VST processing plug-ins called The Blue Line, all contained in a single compact installer file, which is available for free. The plug-ins include BlueChorus, BlueCompressor, BlueDelay, BlueFilter, BlueFlanger, BlueGate, BlueMultitap, BlueParamEQ, BluePhaser and BlueReverb.
The basic interface for each plug-in is the same. All controls appear as virtual “faders,” with other options appearing as buttons. Each plugin features the ability to save and recall presets, as well as perform A/B comparisons. I preferred the fader-style controls to the virtual “knobs” I’ve seen on many other plug-ins.
There are at least two conventions regarding how to turn a “knob” with a mouse, either up for clockwise and down for counterclockwise, or right for clockwise and left for counterclockwise. I’ve even seen ones where the knob has to be dragged using a circular motion. Faders leave little guesswork.
The layout of these plug-ins is reminiscent of the old rackmount processors they replace, so they’re intuitive. The BlueChorus chorus, BlueDelay delay, BlueFlanger flanger and BluePhaser phaser operate very much like the old effect stomp boxes I used when I played in a garage band about 100 years ago. The BlueParamEQ parametric EQ is similar to what one might find on a large recording console. The two midrange sections are truly parametric, offering cut/boost, frequency and bandwidth controls; but the high and low sections omit the bandwidth control. The BlueFilter filter essentially is a single-band EQ, operating as any of several filters, such as low-pass, high-pass and band-pass. It also includes a low-frequency oscillator for more interesting effects.
The BlueGate offers more surgical control of the signal than a traditional noise gate, including individual adjustments for attack, sustain, release and decay. The BlueCompressor compressor is straightforward and easy to use and includes input, output and gain reduction metering.
The BlueMultitap delay allows for up to eight separate delay signals, all of which can be individually adjusted for level and pan. The BlueReverb is a simple, bare-bones design, with six basic “spaces” to choose from and fine tune with available time, diffusion and damping controls.
Overall sound quality on these plug-ins is good. The “stomp-box” effects and the BlueChorus, BluePhaser, BlueFlanger and BlueDelay effects were clean and smooth-sounding. My only complaint here was with the delay. Adjusting some parameters while audio was playing generated some popping artifacts. Keeping monitor levels low while making such adjustments might be prudent.
The BlueCompressor did its job well, but the gain reduction meter seemed to lag a bit on transient material. The BlueReverb didn’t exhibit any of the artifacts I’ve heard on other free reverbs, even on transient sources. The BlueFilter plug-in was a bit confusing at first and took considerable experimentation to get the hang of, but certainly works as intended.
A nice effort on the part of Herr Stahlberg, and a much appreciated gift to the digital audio community.