H3000 Series

01 Overview

Beyond pitch shifting

1. 1

   Pitch shifting in key

   The H3000 introduced diatonic pitch shifting: it analyzes the input pitch and creates harmonies that follow the selected key.^{1, 2} → Algorithms

2. 2

   Build effects by connecting modules

   Patch Factory and mod factory, added through later models and upgrades, let users patch together pitch shifters, filters, delays, LFOs and envelope detectors to create new effects.^{3, 4} → Modular algorithms

3. 3

   Expanded through upgrades

   The original 11 algorithms continued to grow through 1994. Owners of earlier units could add new algorithms and programs through upgrades.^{1, 3, 5} → Models

4. 4

   From studios to stages

   It found a place in personal studios and in front of house mixes on major tours.^{6, 7, 8} Hardware H3000 units still appear in accounts of record production from the 2020s.^{9, 10, 11} → Reviews · In use

02 Development and launch

How the H3000 came about

Development began as a stereo redesign of the H969.¹² The service manual also describes the original design goal as a stereo pitch shifter.¹³ Bogdanowicz recalled that the plan was to build a stereo pitch shifter, but the team “got carried away.”¹² The finished unit was a multi-effects processor combining diatonic pitch shifting, delay and reverb.^{1, 2} Ken Bogdanowicz developed the algorithms and Bob Belcher the hardware.¹² Dave Derr designed the analog circuitry and helped with the interface and presets.¹⁴

Unveiled at AES New York in 1987

First unveiled on October 16–19, 1987, at the 83rd AES Convention in New York.^{2, 16} Coverage from the show named the H3000 as one of its three most noteworthy new products.¹⁷ Launch advertisements appeared in February 1988 magazines; Eventide also lists 1988 as the release year.^{18, 28} The US price was $2,395;¹⁷ the UK price was £1,795 excluding VAT.¹ Some reports gave the US price as $2,400.² British reviewer David Mellor noted that it actually cost less than previous Eventide Harmonizers.¹

In 1990, the subsequent H3000-SE won the TEC Award for signal processing technology.²¹

03 Contemporary reviews

Contemporary reviews

Reviewers praised the pitch shifting, delay and MIDI implementation, while noting output noise and pitch-shifting glitches and artifacts. Opinions on the reverb differed.

04 Documented use

In the studio and on stage

In recording and live sound, the H3000 has been used to widen vocals and guitars, add doubling and create a sense of space.

• 2022Width for a lead vocal

  On Red Hot Chili Peppers’ Unlimited Love, Ryan Hewitt used Doubler or Micro Pitch Shift settings at +12 and −12 cents to give the lead vocal dimension and width.¹⁰

• 1993Subtle pitch offsets on guitar

  On Chris de Burgh’s “By My Side,” Stephen Tayler occasionally added very slight left and right pitch shifts to the electric guitar delays for extra resonance.³⁰

• 2016 · 2025Live vocal doubling

  Marc Carolan used an H3000-D/SE to double vocals for Muse, and later used a hardware H3000 on vocals for Snow Patrol as well.^{31, 32}

Hardware in an in-the-box era

A 1994 report described the H3000-S as a studio staple.²⁵ The H3000 remained on sale in 2001, after its successors had arrived. Studio Sound’s Eclipse review noted that, although the newer units were technically more advanced, there was something more immediate and solid about the approachable H3000.²⁶ It entered the TECnology Hall of Fame in 2016.²⁷

In a 2021 interview, Jonathan Low explained that he mixed folklore entirely in the box and that the two hardware units he mainly used for in-the-box mixing were the H3000 and Culture Vulture. He said he used the H3000 because he had not found a plug-in that could produce the same effect.³⁸

05 Design

Hardware architecture

The H3000 processes audio with three Texas Instruments TMS32010 DSPs.^{43, 44} A separate 8-bit 6809-family CPU handles the front panel and MIDI input, passing programs and parameters to the DSPs.⁴³

The output D/A converters run either on a fixed 44.1 kHz clock, matching the input, or on variable clocks of 22–88 kHz produced by two frequency synthesizers. The service manual describes the variable clocks as a way to change pitch without digital decimation or interpolation filters.⁴⁵

Explore the circuitry and componentsConverter circuits · component photos · manufacturer specifications

Designers Bogdanowicz and Belcher presented a paper on multiprocessor-based real-time audio effects processing at the 7th AES International Conference in May 1989.⁵¹

Each DSP has 2K words of program memory and time for 104 single-cycle instructions per 44.1 kHz sample period. Branches, subroutine calls and I/O instructions take longer.⁴³ The three DSPs exchange data over a shared bus and three 16-bit registers called mailboxes.^{13, 43, 52}

The 64K-word delay memory provides up to 1.5 seconds of delay.^{45, 46} A single two-channel 16-bit A/D converter (CX20018) alternates between the input channels. Two Burr-Brown PCM53 D/A converters handle the left and right outputs separately.^{45, 47, 48} User program memory is 8K × 8 bits (8 KB).^{53, 54}

The audio inputs and outputs use balanced XLR connectors.⁵⁵ Internal jumpers select an input reference level of +4 dBm or –10 dBm.⁵⁶ Before the A/D converter are high-frequency pre-emphasis and a ninth-order low-pass filter.⁴⁷ After the D/A converters are the same ninth-order filters, Sin(x)/x correction and de-emphasis.^{48, 57} Bypass uses relays to connect inputs directly to outputs and engages automatically when power is off.^{48, 50}

Key components

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

Manufacturer specifications⁶²

• Conversion 16-bit · 44.1 kHz
• Frequency response 5 Hz–20 kHz ±1 dB
• Dynamic range 92 dB or better (A-weighted)
• Distortion 0.01 %(1 kHz)
• Dimensions · power 2U rack (3.5 × 19 × 13.5 inches) · 75 W

06 Interface

Operation and control

Recall a program by number, then edit its displayed parameters with the knob or keypad.^{50, 63, 64} The upper line of the 2 × 40-character LCD shows the program number and name, or the parameter or function being edited. The lower line shows the functions of the four soft keys.^{65, 66, 67} PROGRAM opens program management; FUNCTION provides display contrast, Soft Functions, Function Generator and MIDI settings; PARAMETER opens parameter editing.⁶⁶

Panel operation and MIDI control

Selecting and editing programs

Enter a program number (0–999) on the keypad and press ENT to recall it.^{50, 68} The Origin soft key displays the algorithm on which the program is based.⁵⁰

MIDI and internal modulation

There are three parameter modulation sources: MIDI, the built-in Function Generator LFO, and Soft Functions, which let one control move several parameters at once.^{63, 69} Each modulation source varies parameters relative to the values set on the front panel.⁷⁰ Function Generator and Soft Functions were added in software version 2.x.⁷¹

07 Capabilities

Algorithms and presets

The first H3000 contained 11 algorithms covering pitch shifting, delay and reverb, numbered 100–110.^{29, 72} Later models expanded into modular effects, sampling and more.⁷³ In the series, numbers 100–123 identify both algorithms and their default programs; factory presets occupy numbers 150–999.⁷⁴

Pitch shifting and chorus

Presets range from subtle detuning that widens vocals and instruments to reverse echoes and choruses built from layered delays.

#519 MICROPITCHSHIFT

Uses 116 Multi-Shift. The manual describes Multi-Shift as an algorithm refined for small pitch shifts,⁷⁵ and this preset as adding thickness and width without coloring the sound.⁷⁶

#231 MICROPITCHSHIFT

Uses 101 Layered Shift. The manual describes it as adding thickness and width without coloring the sound.⁷⁶

#515 MAGIC AIR

Uses 101 Layered Shift. The manual describes two closely spaced upward pitch shifts and delays, useful for lifting a slightly flat vocal or thickening a sound.⁷⁶

#217 DUAL H910S

Uses 102 Dual Shift, configured to behave like two H910s. The manual states that the audible glitching is intentional.⁷⁶

#642 CRYSTAL ECHOES

Uses 104 Reverse Shift. The manual describes it as a “staircase of echoes ascending into the sky.”⁷⁶

#527 RICH CHORUS

Creates chorus with the six delay lines of 105 Swept Combs.⁷⁶

Style I in Soundtoys MicroShift was modeled on #231; Style II on #519.⁷⁷ Soundtoys Crystallizer also draws on the pitch shifting and reverse echoes of Reverse Shift and Crystal Echoes.⁷⁸

Delay and filters

Presets differ in the placement and tone of their repeats. Low-pass filtered echoes, ping-pong repeats and delays moving across frequency bands create different rhythms and spaces.⁷⁶

#535 ANALOG DELAYS

Warm echoes with the high end reduced by the low-pass filter in 111 Patch Factory.

#540 ECHOPLEXINGPONG

Uses 110 Dual Digiplex to alternate echoes between left and right.

#638 BAND SWEEP

In 117 Band Delay, the filter band sweeps upward as the delayed sound moves from left to right.

Reverb and space

H3000 reverbs include modulated plates, punchy gated ambience for drums, and warm, long rooms.⁷⁶ Presets with the same or similar names as RICH PLATE, BIG SNARE and BOB’S ROOM also appeared in the Eclipse. Eventide’s cross-reference identifies only #578 BOB’S ROOM as retaining its original number. RICH PLATE and BIG SNARE came from other presets with the same names, #243 and #206.⁷⁹

#586 RICH PLATE

Uses 106 Swept Reverb with a gentle sweep. The manual describes a rich sound and a smooth tail.

#576 BIG SNARE

A drum reverb built with 107 Reverb Factory, described in the manual as punchy and slightly gated.

#578 BOB'S ROOM

A room preset using 114 Dense Room. The manual describes a warm, long reverb suitable for many sources.

Modular algorithms

Patch Factory (111) and mod factory (122 and 123) let users edit signal routing as well as module parameters. Connecting the inputs and outputs of pitch shifters, filters and delays lets users design the structure of an effect.^{3, 4}

The LFOs and envelope detectors in mod factory modulate delay time, filter frequency, output level and other parameters. They can create delays and sweeps locked to a song’s tempo (30–200 BPM), or duck the delay output as the input grows louder. It came with 100 presets using these modulation capabilities, numbered 800–899.^{3, 4, 72}

mod factory’s COOL PRES, RICH RHYTHM and UNDULATOR create a range of spaces and rhythms, from input-responsive delays to repeats layered with chorus and tremolo.⁷⁶

#162 COOL PRES

A warm, complex delay that changes dynamically with the input. A mod factory preset outside the 800 bank, included in the D/SX, D/SE and H3500.

#873 RICH RHYTHM

Spreads a pair of chorused repeating delays across the stereo field. Echo tempo is set in BPM.

#893 UNDULATOR

Layers tremolo over a multitap delay.

08 Series

Model configurations

The H3000 series shared its basic hardware, expanding capabilities through ROM changes and expansion boards.³ Factory presets grew from 50 in the first model to over 400 in the H3500, which had 23 algorithms.^{1, 3, 29, 80} Figures vary by source. Eventide lists 100 presets for the first model;⁵ H3500 reviews list either 404 or around 450 presets,^{3, 80} and either 23 or 20 algorithms.^{24, 80}

mod factory is an algorithm package created by Crescent Engineering.^{23, 81} Introduced for the H3000 in March 1992,²³ it was included as standard in the H3500 released that year.⁴ H3500 reviews noted that mod factory and the sampling algorithms had previously been options for the 3000 series, available as a $250 upgrade for existing units.^{24, 80} By 1994, mod factory was standard in the B+, B/LT, D/SX and D/SE.^{5, 75} The D/SX was announced as adding mod factory, a 19-waveform Function Generator and a six-octave Multi-Shift algorithm to the original 11 algorithms and presets.²⁵

Model configurations and front panels1987–1994

Main changes by model^{4, 5, 19, 29}

Year	Models	Main changes
1987	H3000	Original model, algorithms 100–110 (11 total).1, 72
1988	H3000-S (Studio)	Same algorithms, with additional presets and features.5
1989	H3000-SE (Special Edition)	Additional algorithms; 200 presets.3, 19, 29
1989	H3000-B (Broadcast)	Broadcast algorithms and presets; tape machine speed control through Timesqueeze. Eventide’s history dates it to 1990.5, 19, 82
1992	H3500	SE features plus mod factory (algorithms 122 and 123, 100 presets) and a sampler card (11.8 seconds stereo; 47.5 seconds on the dfx/e).4, 73, 81
1994	H3000-B+ · B/LT	B plus mod factory. The B/LT omits Timesqueeze and the tape speed control hardware from the B+.5, 75
1994	H3000-D/SX · D/SE	Adds mod factory.5, 75

Identifying the front panels⁷²

H3000-S

Blue panel

H3000-SE

Gray panel

H3000-B

Black panel, yellow buttons

H3000-D/SX

Black panel, orange wave across the top, script model name

H3000-D/SE

Black panel, red “Dynamic” script⁸⁴

H3500

Dark gray panel, marked “MODEL H3500” and “DFX-SAMPLING”

Photo 2 shows a unit upgraded to SE while retaining its S front panel.⁵⁸

09 Today

The H3000 today

The H3000 remains in studios and touring racks after factory repairs have ended. Owners and independent repair shops now keep the units running.

The end of factory support

A 2003 Eventide technical note attributed most problems to connectors rather than failed components.⁸⁵ In 2014, an employee said factory repairs were still available but could be expensive.⁸⁶ In March 2016, Eventide said it could no longer support or repair the unit; that October, it noted that the one person familiar with it had retired.^{87, 88} In 2020, it said nobody with that knowledge remained.⁸⁹ An Eventide reply shared by a user in 2022 stated that no parts remained, including the self-test ROM.⁹⁰ Archived official store pages show model conversion kits in 2007, only a battery-backed memory chip by 2015, and the last archived listing for that chip in 2017. The service manual, sold for a fee in 2012, is now available free alongside the user and D/SX manuals.^{72, 91}

What goes wrong

In reported forum posts, repair accounts and used listings, power supply issues—transformer hum and shorted tantalum capacitors—appear most often, followed by connectors (Molex power connectors and IC sockets), EPROMs, battery-backed memory, displays, switches and jog wheels. Common symptoms include units that power on and display normally but sound wrong, and units that freeze during boot.⁹² These are counts of reported cases, not failure rates. One report describes a unit stopping during recording with “Uh Oh... TMS320 Loading Error.”⁹³ The battery is integrated into the memory chip, so the whole chip must be replaced, erasing saved presets and settings. The service manual gives a battery life of 10 years; a 2004 technical note says around five.^{53, 94}

Two minutes, $26

A technician fixed an H3000-D/SE that jumped to the initialization screen and flickered by blowing dust out of its power connector (2011).⁹⁵

A discarded unit

An H3000 recovered from a dump produced no effects because of a shorted tantalum capacitor on a power rail. Its owner replaced all the tantalum capacitors and restored it (2022).⁹⁶

A fault without a replacement part

The jog wheel’s optical encoder was discontinued, with no stock at Eventide. A technical note suggested changing the value of a resistor beside the encoder.⁹⁷

Keeping units running

Repair accounts usually begin with inexpensive steps: cleaning or reseating power connectors and pressing socketed chips firmly into place,⁸⁵ then initializing memory by powering on while holding FUNCTION. The manual describes initialization as a procedure for rare cases.⁹⁸ Next come battery-backed memory replacement, capacitor replacement and replacement of parts such as D/A converters or filters.⁹² Repair providers have changed too. Studio Electronics, an independent shop Eventide recommended when it ended repairs in 2016, listed typical repair costs of $275–475 in its 2008 archived page and $820 in 2022.^{87, 99} It disappeared from Eventide’s list around 2024. Its current Eventide notice says it no longer works on digital models.^{99, 100} Eventide currently lists independent repair shops in two US locations, Paris, Hamburg and Glasgow.¹⁰¹

Modifications and upgrades

Many units in use today are no longer in factory condition. OLED display kits, new power supplies to eliminate transformer hum and battery-free memory kits are sold,¹⁰² as are replacements for the discontinued Murata filters.⁹⁶ Since official upgrade kits disappeared, third-party EPROM sets have become a common way to add H3500-level algorithms and presets.^{92, 93} We found no evidence that these sets were authorized by Eventide. Displays and power supplies sit outside the audio path, while filters, D/A converters and capacitors are within it. An H3000’s sound today may therefore depend on its service history. We found no measurements quantifying those differences.

Use and value today

Physical H3000s still appear in touring racks in the 2020s. Beyond the examples above, an engineer on Bruno Mars’ 2026 tour reported using one on vocals,¹⁰⁴ while a Weezer tour engineer said he brought an Eclipse or H3000-D/SE only to shows that did not involve air travel.¹⁰⁵ Reasons for continued use include the lack of a plug-in producing the same effect,³⁸ the presence of “that sound,”³² and the String Modeller algorithm and converter texture unavailable in other models.¹⁰⁶ Other engineers have moved entirely from outboard equipment to plug-ins.¹⁰⁷

Used prices have risen. Across 753 Reverb transactions, annual median prices were about $1,200 in 2017, $2,300 in 2021 and $2,650 in 2026. The H3000-D/SE was the most traded model. These figures cover Reverb transactions only, excluding eBay.¹⁰⁸

The 1996 manual includes advice for long service: set the rear voltage selector correctly (115 or 220 V), keep upper and lower vents clear because “heat is the enemy of reliability,” and save presets before receiving a MIDI dump. It lists input XLR pin 3 as hot.⁹⁸ Users therefore advise checking pin 2 and 3 polarity when connecting other equipment.¹⁰⁹

Preserving the documentation

Eventide offers the user manual, service manual and D/SX manual as free downloads.⁷² In 2024, users decoded MIDI dump data and released an H3000 editor.¹⁰⁶ In 2025, a user published a table of algorithms and presets across all models.¹¹⁰