Your browser is out-of-date!

Update your browser to view this website correctly. Update my browser now


TC Helicon VoiceOne Voice Pitch and Modeling Tool

Now arrives the VoiceOne by TC Helicon. This amazing rackmount device provides pitch correction, but also allows control of all sorts of vocal parameters: vibrato, growl, breath, pitch shifting, inflection, spectrum and resonance. As a result, singers can greatly increase the range of their vocal character beyond what they could do naturally.

Ever since an engineer made the first tape splice, audio technology has been used to improve musical performances. First we had tape editing, then overdubbing and punching in, then DAW editing. Recently we marveled at Antares Audio Technologies’ AutoTune, which corrects off-pitch notes.
Product PointsApplications: Studio, live sound

Key Features:Numerous effects; digital I/O; 100 factory presets; 50 user presets

Price: $1,299

Contact: TC Helicon/TC Electronic at 805-373-1828, Web Site and


+ Realistic pitch correction and pitch shifting

+ Unique control over many vocal parameters

+ High-quality construction and sound


– None

The Score: A do-it-all pitch shift and correction box that handles modeling as well.
Now arrives the VoiceOne by TC Helicon. This amazing rackmount device provides pitch correction, but also allows control of all sorts of vocal parameters: vibrato, growl, breath, pitch shifting, inflection, spectrum and resonance. As a result, singers can greatly increase the range of their vocal character beyond what they could do naturally.


On the neat front panel of the VoiceOne are buttons that select the effects mentioned. Other buttons are I/O (choice of analog or digital in and out), Store and Recall of presets (user or factory), and MIDI/Utility (MIDI and other general parameters). Input and output knobs adjust the levels in and out. Arrow keys are used to scroll through parameters when you edit an effect. An edit wheel selects either the preset number you want to recall, or sets the value of a parameter during editing. The Enter button confirms a parameter edit or function, while the bypass key is used to bypass all effects.

A multicolor LCD display shows the preset name and number and the effects parameters. It also helps you go through the menu and select parameter values.

On the rear panel are two balanced XLR line inputs. One or the other channel is selectable. Outputs are a pair of balanced XLRs. One channel feeds the dry signal; the other, the voice-modeled signal. Other connectors include S/PDIF digital in and out (24-bit, 44.1 kHz and 48 kHz), MIDI In/Out/Thru, and a footswitch jack. You may use an analog input and a digital output, or vice versa. You may also use both analog and digital outputs at the same time.

A line level device, the VoiceOne can be inserted in-line with the signal, or placed in an effects loop. Set your mixer’s aux send to prefader if you want to hear only the processed signal.

MIDI IN connects to a MIDI controller or sequencer, which can switch different parameters on different MIDI channels. This lets you use a keyboard to “play” the expression of a vocal performance. MIDI OUT provides a MIDI pitch output to a sequencer or sound module. You can also connect the MIDI ports to a sequencer, librarian or another VoiceOne to send and receive preset dumps via MIDI system exclusive (SYSEX).

Pitch correction corrects flat or sharp notes to the nearest note of the scale. The VoiceOne offers a huge number of scales to choose from, such as Minor, Dorian, Pentatonic, Blues and so on. Pitch shift moves the vocal up or down in pitch (up to ±2 octaves) without changing its duration or character. It can be set to create harmonies.

As a unique feature, VoiceOne offers Vocal-trained Pitch Recognition, an algorithm written specifically for the human voice. The formant-corrected pitch shifting is claimed to preserve voice characteristics even with large pitch changes.

Another feature called PureShift enables only the pitch-shifting effects in the VoiceOne, increasing the processing power to create higher quality and less latency.

Then there are the voice modeling effects.

Inflection varies the pitch in controlled ways, such as sliding into notes. A proprietary feature of the Inflection effect is FlexTime, which lets you alter the timing of a vocal track by slowing down or speeding up the rate without changing the pitch. When you use a harmony or doubling effect, FlexTime decorrelates the dry and processed vocals, making them more distinct.

Vibrato is human modeled frequency and amplitude modulation of the voice with adjustable speed and depth. Spectral provides a variety of EQ settings for adjusting tonal balance.

Breath controls the amount of breathiness, ranging from a rasp to a whisper. Growl adds a fair simulation of growling to notes, and Resonance varies the harmonic content to make the voice sound chesty, nasal or anywhere in between.

Each of these effects can be tweaked extensively from subtle to outrageous. You can make adjustments and save your own presets (up to 50), or use the 100 built-in presets. Also included are other features such as an adaptive low-cut filter, adjustable bit resolution and dithering.

In Use

The VoiceOne is easy to use. To adjust an effect such as Resonance, double-tap the Resonance button. Then press the up or down arrow to select a parameter of Resonance. Finally, turn the Edit knob to tweak the parameter. It helps to set each effect to maximum to hear it easily, then back off to a tasteful amount. If you wish, save the preset under a name of your choice.

As I ran the VoiceOne through its paces, I noticed that the LCD screen was clear and readable. So is the user manual, which tells you everything you need to know. It includes full information on MIDI implementation.

I am impressed by the quality of the pitch correction and pitch shifting. Artifacts are subtle or nonexistent. Changes in pitch are believable, as if the vocalist actually sang that way. Even extreme pitch changes sound natural and seamless, not like a chipmunk or robot.

Playing with the VoiceOne is a blast. Resonance effects, for example, turn the singer into an R&B stylist, a Sumo wrestler or a slinky pop star. Imagine singing out of your chest, throat or nose, and you get the idea. I was amazed to hear the Whisper preset, which removes the voice and substitutes breath. Yet all the words are clearly pronounced.

The presets have clever, descriptive names like “Phlegmmy” or “Tracheotomy.” Even the vibrato effect is divided into different styles, such as “Opera,” “Pop,” “Deep Jazz” and “Folk.” Not all of the presets seem useful, yet they might be just right for video or cinema productions and radio spots.


The TC Helicon VoiceOne is a technical tour-de-force. Clearly, it required a huge amount of research into vocal styles and the relationship between audio and speech physiology. Thanks to the VoiceOne’s sophisticated algorithms, the sound quality is excellent. It will not turn a mediocre singer into Celine Dion, but it can enhance the vocal style and tone if used with care.

Without a doubt, the VoiceOne opens up a whole new world of effects. I cannot wait to try “Growl” on a flute or “Vibrato” on a cymbal!

Review Setup

NHT Pro A-20 monitors; TASCAM DA-88 recorder; Mackie 1604VLZ mixer.