Eventide H949 Harmonizer

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2003-05-25: Love at first sight

I just fell in love with a girl called Eve...
Met her on a website, made contact, money changed hands...

She's 26 years old and quite beautiful.

OK, maybe I should divulge her full name: Eventide H949 Harmonizer - a classic bit of vintage gear from 1977.

We are talking seriously cosmic delay / pitch-shift / time-reversal / time-compression / flanging / chorus / space-effects machine here. This baby was way ahead of its time, using 16-bit digital processing and a 400ms delay time with 15kHz bandwidth, the Orville of its day, costing big bucks back then in a mostly analogue era long before sampling and even computers became common outside laboratories.

Nice Touches

Besides manual control (*real* dials and switches) there are facilities for voltage control of pitch-shifting from a CV monosynth, special keyboard or even a microcomputer (we're talking Commodore PET 2001 era!) via IEEE488 (great grand-daddy of IEEE1394 aka FireWire).

[UPDATE: I just found out that this unit has the optional ALG-3 de-glitch board (or "lupine board"), as indicated by the badge on the rear panel. The de-glitch option was not included on most H949's but greatly improves the harmonizing function and is a valuable plus :-]

Other nice touches include LEDs which change colour depending on the mode of operation. Working in parallel with the chorus/pitch-change/flange modes (multi-fx in 1977!), there are two sets of switches to independently delay the Main Output and Delay Output (separate XLR outputs) by 6.25, 12.5, 25, 50, 100 and 200ms. These amounts can be combined by pushing the required switches to give a maximum delay time of 393.75ms (which pulses at 152bpm), but sadly there is no way to continuously vary the delay time, and pressing a switch causes a noticeable click. Each output has its own Feedback level - use with care or be swamped by invading aliens!


[ Malc dreams of making beautiful music with Eve ]Sadly, having nothing in my spartan studio with XLR outputs on to hook up to it yet, I was wondering how to check out that the unit was operational. I figured out that I could patch the delay and main outputs to each channel of my DAT machine's XLR inputs, and then buy a jack-to-XLR lead to plug in my keyboard. But then I discovered the FEEDBACK controls...

...wow! This is awesome. I just switched the thing on and a whole Forbidden Planet soundtrack unfolded before my headphoned ears... This machine is amazing even with no input to process! I've played with delays and flangers before, but this is alive, mutating, unpredictable, a creative tool in its own right.

She is oh so responsive to the slightest touch...
Now if only I can learn to tame her wild ways...

2003-05-27: Meltdown in Space

I just recorded another 40-minute epic space voyage, direct to DAT, this time using just the Pitch Change setting under Manual Control. Starting with take-off from a launchpad, then hovering over a planet's surface with wonderful 3D effects as if echoes from near and distant mountains. Some alien lifeforms appeared too, singing their angelic and demonic songs. [Sadly the tape has been lost; hopefully it can be recreated.]


The trick is in keeping enough thrust to maintain altitude (amplitude) without overloading the warp engines Captain (clipping). Any thrust applied (oooer Missus!) takes effect a few delay cycles later (about a second), so once a feedback reaction gets out of control it rapidly overloads the output. Hence the need to ride the levels constantly, fading up as the signal pulses down and vice versa. Subtley nudging the Pitch Ratio by 0.1% or so causes remarkable shifts in timbre, and changing the High and Low EQ brings out shimmering crystal tones and bass pulses respectively.

I can envisage a great performance instrument using these techniques with more hardware to make the process more easily controllable: a mixer with long-throw faders, the inputs and outputs patched into similar feedback chains with this device on an effects loop, its input guarded by a compressor and a brickwall limiter to prevent overs.

--Malc (very excited about my first proper rackmount unit, first of many :-)

2003-06-12: Wedding Photos

Wedding photos - click to enlarge (carefully caressed and tenderly touched with The GIMP - spot the joins)...

[ Eve posing on the bonnet of my car | Eve on the bonnet of my car, taken from behind ]

[ Eve on the street | Eve lying on my bed | Eve reclining on my bed with LED's ablaze ]

[ Eve reclining on the bed with instructions | Eve lying on my bed in sunlight | Eve on car roof | Eve's rear on car roof ]

[ Eve's front with manual | Eve on roof with manual | Eve front left with manual, joke wearing thin | Eve sunbathing outside honeymoon cottage ]

(This page probably has more pictures of an H949 than the rest of the internet put together... It is dedicated to the Photographic Society at my old University, many of whom believed that pictures of women posing on cars was the true essence of photography. Sad people...)

Design Classic

Synth and audio gear designers take note: standards are slipping! They don't build 'em like they used to! You can tell this is/was a quality product just by its looks and over-engineered build quality; so much modern gear just isn't in the same class - and they must be good if Conny Plank, Klaus Schulze and Led Zeppelin used them. I've also read that this was John Lennon's favourite effect. Tony Visconti described it thus:

I actually said, "It fucks with the fabric of time," much to the delight of David [Bowie] and Brian [Eno].

Check out the interconnectivity on the rear panel, complete with outputs for controlling the speed of an analogue tape machine. The manual is excellent, describing the various modes of operation in great detail, with an extensive Technical Section which includes enough circuit diagrams to ensure that she'll run for another 26 years.

I shall report back when I finally get something plugged into this thing... Jon Hassell here we come!

[UPDATE 2014-08-27: OMG! I later also acquired a splendid Eventide PS-101 Instant Phaser, as used by Isao Tomita, and made famous by Led Zep on the drums at the end of "Kashmir"! More about this another day... :-]

2003-06-23: Jupiter Mission

Playing Jupiter and Eve ] Playing 'When Roland Met Eve' | [ Eve with Roland Jupiter 6 polysynth !OK, I found another heavenly body to link Her up to... Sublime!

Beyond ecstasy, I recorded two improvisations entitled "When Roland Met Eve" ;-)

2004-02-13: Experimental Virtual Environment

Virtual Reality fans may like to check out big sister EVE.

Eventides appear occasionally on eBay, sometimes for serious prices.

2005-06-27: Ululating Feedback Occultifier

[ Ululating Feedback Occultifier rack ]The next plan is to connect up Eve as part of a larger mega-process called Ululating Feedback Occultifier (U.F.O.). This will use an effects send from the mixer which is routed through comprehensive EQ and filtering (superseding Eve's own Treble and Bass controls) before a compressor/limiter on Eve's input (to prevent distortion). The Delay output is sent to a separate mixer channel which can then be fed back into the effects send circuit again, to create cosmic space echoes with less risk of blowing the place up when the process goes into sudden meltdown. Here's a rough ASCII-art diagram.

© copyright Malcolm Smith 2003-06-12 - last updated 2017-09-09 - links verified 2003-06-12