The Empress Tremolo is a tremolo pedal from Empress Effects, the Canadian company's first tremolo pedal and an original design built, as the maker puts it, "from the ground up to include innovative features"1. It is a hybrid design: the audio signal path is analog, but the tremolo effect itself is controlled digitally via opto technology, the same light-based approach that produces the tremolo in vintage tube amplifiers1. Empress describes the result as "whisper quiet and free from the 'LFO throb' usually associated with tremolos"1.
What sets it apart from a basic tremolo box is rhythm control. Beyond speed and depth you get three waveforms, an eight-position rhythm selector, tap tempo that averages your last four taps, and a two-speed mode. It lists at $249.00 USD and comes with a two-year warranty1.
What it does: opto tremolo with three waveforms
Tremolo raises and lowers the volume of your signal in a repeating cycle. The Empress Tremolo does this with an opto circuit, where a light-dependent element controls the signal level, and offers three waveforms to shape the character of that cycle1:
- Asymmetrical: Empress says this waveform was modeled after a '65 Fender Vibrolux (brown face) "to give you the fullest tremolo sound possible"1. Vintage Guitar's review described this position as a tube-style waveform2.
- Square: A hard on/off cycling that produces a strong, choppy tremolo2.
- Triangle: The traditional smooth tremolo sound offered by most pedals2.
Because the audio path stays analog and only the modulation is digital, the pedal behaves like a vintage amp tremolo in the signal chain while still allowing precise digital control of speed and rhythm. Empress specs the frequency response at 6Hz to 30kHz (-3dB), distortion at 0.025% and noise at -104dB1.
The controls: waveforms, rhythm selector and tap tempo
The front panel combines knobs for Depth, Rate/Ratio, Rhythm and Gain with two mini-toggle switches and two footswitches: a heavy-duty true-bypass switch and a Tap stompswitch2.
| Control | What it does |
|---|---|
| Depth | Adjusts how deep the volume swell and dip goes2 |
| Rate/Ratio | Sets tremolo speed, or the note value relative to your tap when in Tap Tempo mode2 |
| Rhythm | Eight-position selector; position 1 is traditional even tremolo, positions 2 through 8 add pulsing-rhythm trem effects2 |
| Gain | Sets the output level2 |
| Waveform switch | Three positions: triangle, square and tube2 |
| Mode switch | Three positions: Tap Tempo, Normal and two-speed2 |
The tap tempo is the pedal's headline feature. Empress says it "averages your last four taps so it plays in sync with your music," and you can choose tap-to-tremolo rate ratios of 1:1, 1:2 and 1:4, so the tremolo can pulse on the whole note, half note or quarter note of your tapped tempo12. In two-speed mode you set two different tremolo speeds using the Rate control and the Tap switch, then move between them2.
The rhythm selector is what pushes the pedal beyond standard tremolo territory: positions 2 through 8 layer pulsing rhythmic patterns over the basic swell, which Vintage Guitar's reviewer counted among its "cool, very usable proprietary features"2.
Power and connections
The pedal runs on 9V DC through a 2.1mm barrel connector and requires 30mA1. It does not operate on battery power, so it needs a power supply or an isolated output on a pedalboard power brick2. Connections are a single 1/4" input and output, with input impedance of 475kΩ and output impedance of 250Ω1. The enclosure measures approximately 4.5" by 3.5" by 1.5" and weighs 1lb1.
The 10th Anniversary Tremolo
In December 2016, Empress marked ten years with a limited edition of the pedal, the Empress Effects 10th Anniversary Tremolo345. Only 250 were made, each with its serial number engraved on the front3. It carried the same $249.00 USD list price, with $10 from each sale donated to Big Sky Ranch, Ottawa's only no-kill animal shelter36. Serial number 1 was signed by Andy Summers and auctioned for charity, with all proceeds going to charity, and ten more pedals were given away in a contest running December 6th to 20th, 20166.
The Anniversary version is more than a cosmetic reissue. It adds several features the original does not have3:
- Up to 8 presets, recalled at the touch of a button
- A control port accepting an expression pedal, external tap, control voltage and MIDI, with MIDI configuration available through an advanced configuration menu
- Extra tap-to-rate ratios: 1:1, 3:4, 1:2, 1:3 and 1:4
- Buffered bypass as an alternative to true bypass
Its internals differ as well: 100mA power draw at 9V DC (negative tip), 1 Meg input impedance, 330 Ohm output impedance, 4Hz to 30kHz frequency response, 0.40% distortion, a signal-to-noise ratio of 107.7dB, and a die cast aluminum enclosure in the same approximate 4.5" by 3.5" by 1.5" footprint3.
What reviewers said
Vintage Guitar reviewed the pedal in November 2007 and was positive about both its features and its quietness2:
"With its cool, very usable proprietary features and the fact it's very quiet, the Empress Tremolo pedal gets very high marks all around2."
MusicRadar, covering the 10th Anniversary launch, described it as a limited edition of Empress's first tremolo pedal4.
Questions
Is the Empress Tremolo true bypass?
Yes. Empress states the Tremolo employs true bypass, so it is not affecting the signal when disengaged. Vintage Guitar's 2007 review also describes it as having a heavy-duty true-bypass footswitch. The 10th Anniversary version keeps true bypass but adds a buffered bypass option selectable through its configuration menu.
How much current does the Empress Tremolo draw?
The Empress Tremolo requires 30mA at 9V DC through a 2.1mm barrel connector. The 10th Anniversary version draws more, at 100mA, also at 9V DC with a negative tip. Neither version runs on battery power.
What is the difference between the Empress Tremolo and the 10th Anniversary Tremolo?
The 10th Anniversary Tremolo is a limited edition of 250 units, each with its serial number engraved on the front. It adds up to 8 presets, a control port for expression pedal, external tap, control voltage and MIDI, extra tap-to-rate ratios (1:1, 3:4, 1:2, 1:3 and 1:4), and a buffered bypass option. Both list at $249 USD.
Does the Empress 10th Anniversary Tremolo have MIDI?
Yes, MIDI configuration is available through its advanced configuration menu. Its control port also accepts an expression pedal, external tap and control voltage, so the pedal can be integrated into a larger MIDI-equipped rig.
How many Empress 10th Anniversary Tremolos were made?
Only 250 were made, each with its serial number engraved on the front of the pedal. Empress donated $10 from each sale to Big Sky Ranch, Ottawa's only no-kill animal shelter, and auctioned serial number 1, signed by Andy Summers, for charity.
Is the Empress Tremolo analog or digital?
It is a hybrid. Empress states the audio signal path is analog, but the tremolo effect is controlled digitally via opto technology. The opto approach is the same basic mechanism as the tremolo circuits in vintage tube amplifiers.
Sources (6)
- Tremolo - Empress Effects Inc., Empress Effects Inc.
- Empress Effects Tremolo, Vintage Guitar magazine, 2010-02-10
- 10th Anniversary Tremolo, Empress Effects Inc.
- Empress launches limited-edition 10th anniversary Tremolo pedal, MusicRadar, 2016-12-09
- Empress Effects party on with "10th Anniversary" Tremolo edition, gearnews.com, 2016-12-12
- Empress Effects Unveils 10th Anniversary Tremolo, Premier Guitar, 2016-12-08
