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Lexicon Reflex

Dynamic MIDI Effects Processor By Nick Magnus
Published March 1995

The flood of quality effects units from Lexicon continues unabated. The Reflex takes the familiar Alex format, enhances its front panel editing, adds Lexicon's new Lexi II chip for improved sound quality ,and tops it all off with comprehensive MIDI control facilities. Nick Magnus gets dynamic...

Once the preserve of only the best studios and wealthiest musicians, digital reverbs and effects units have undergone a revolution in recent times. Not only has the price come crashing down around our ears, but quality just seems to keep improving in direct proportion to growing affordability. But when did this revolution start? Let's answer that with another question: how many of you remember the introduction of Yamaha's R1000 in 1984? At £499, it was amazingly inexpensive, particularly compared to the £4,000 price tag of the Ursa Major 8x32, one of the few contemporary alternatives. The R1000 was nevertheless only a mono unit, sporting a mere four settings. Granted, it had built‑in EQ to help smooth out the wrinkles, and people were heard to cheerfully advise buying two; at least that would give you stereo, wouldn't it...? I never did encounter anyone who actually took that plunge; maybe it was something to do with the sound of the R1000... Happily, things took an upward turn for Yamaha in 1985 with the release of the REV7, retailing at £1,199. This piece of kit became a familiar sight in many studios, both private and commercial, and was a welcome replacement for the spring reverbs tolerated up until that time. Roland's SRV2000 provided the REV7 with some stiff competition, and even its higher price of £1,399 seemed quite reasonable. The rest, as they always say, is history. Now step this way to the quantum leap accelerator, which will whisk us forward in time to...

...1993, the year in which Lexicon, the company many consider to be the godfather of digital reverb, launched the Alex. Based around the LXP series of reverb units, and offering 16 presets, 16 user memories and basic editing facilities, the Alex represented a quality/price breakthrough at £389. For those of you just returned from 10 years of missionary work in the Australian outback, a full description of the Alex can be found in the SOS May '93 issue.

The Reflex is a logical development from the Alex, but with a number of refinements that belie its simple exterior. It looks almost identical to the Alex, but a quick glance at the front panel reveals two differences: the Parameter button now has the word 'Learn' added to the legending (more on this later), and the selection of presets is slightly different. The reason for the latter is presumably to include a preset featuring the Reflex's additional Resonator algorithm and to highlight the enhanced programmability of the new machine. The back panel now sports MIDI In and Out/Thru sockets — a clue to another of the major new features. On the inside, the Reflex uses one of the new Lexi II chips developed for the PCM80, providing the latest reverb algorithms. Improvements are particularly noticeable in the definition of the Hall reverb's early reflections, together with a much more natural high‑frequency content (compared with an LXP15). This is not to say that the Reflex is a cheap PCM80, but it could possibly represent the next generation in quality budget effects.

Those keen on creating and customising effects will not be disappointed; in addition to the 16 presets, 128 user memories (or registers) are provided. As already stated, this implies considerably more editing power than the Alex, which is indeed the case. The effects are based around eight algorithms, each of which can have up to 10 parameters altered (see box on Reflex algorithms and Parameters) The first three parameters of each algorithm are always available from the front panel, while the rest are accessed by entering Advanced Programming Mode (APM), which is accomplished by pressing the Preset/Register and Parameter/Learn buttons simultaneously. Once this mode is entered, the Preset selector knob becomes the Parameter selector. The Reflex comes supplied with a very helpful laminated card containing a list of the parameters to guide you through the editing process. Once the desired parameter number is selected, its value is altered with the value knob. The new sound can be stored in any of the 128 registers, which Lexicon have thoughtfully filled with a variety of useful programs. Registers 1‑16 and 113‑128 have copies of the front panel presets, giving you somewhere to write your first 32 edits without fear of losing anything useful. Unusually, if you do overwrite any of registers 17‑112, there is no re‑initialising procedure available to get them back, so a MIDI dump of the entire contents is advisable.

The Alex offered 16 variations of each parameter; the Reflex, however, provides a much wider range in many cases. For example, whilst reverb decay time retains the same 16 increments (quoted at from 0.25‑6.5s, in contrast to the Alex's 0.15‑8.9s), Pre‑delay allows 128 increments, ranging from 0‑246ms, and this improvement is found in many other instances. Certain parameters, such as delay feedback or resonator tuning, also run into negative values.

The Algorithms

    The reverbs, as you would expect from Lexicon, are superb. Fine control of colouration is possible using High Frequency Cutoff and Bass Multiply in conjunction with Room Size (8‑71 meters in 64 steps). The new Hall reverb benefits from Early Reflection level, delay and diffusion parameters, and of particular note is the lovely Plate algorithm. This is full of detail and richness but without a hint of muddiness, making it perfect for all your drum and percussion needs.
    Very transparent in quality, this stereo flanger also incorporates separate left and right delays (0‑1000ms) with individual feedback amounts, plus a Shape control to alter the modulation waveform. With the addition of negative feedback, rate and depth, one is armed with all the essentials of good flanging.
    This 4‑tap bouncing delay is actually two separate ping‑pong delays, each with a range of 0‑1000ms in 128 steps. Use of High Frequency Cutoff and Diffusion serves to respectively darken the tone and blur the edges of successive repeats, providing a pleasing simulation of analogue tape delay. This algorithm also allows the delays to be controlled by MIDI clock. In practice, setting the delay times is quite tricky, as the display shows arbitrary values between 1‑128, not milliseconds, and things are further confused by the Group Delay setting, which varies the delay ratio between left and right repeats. Once a nice relationship is found, it seems to be totally disrupted when MIDI clock is applied; change tempo, and all hell breaks loose. Not for high pressure clock‑watching sessions, but great atmospheric results are possible.
    The Resonator is additional to those algorithms found in the Alex, and is both strange and pleasing. It reacts in subtly different ways depending on the source sound, but the overall impression is of a 'strumming' effect which tails the note, reminiscent of an Aeolian harp, or someone strumming the strings of a piano with the sustain pedal down. The tuning, tone, decay and spread of the strum can all be controlled to some extent, again dependent on the sound being treated. Setting the pre‑delay to long values (0‑524ms) with high feedback can give the impression of an orchestra of psalterys following your every move. Very absorbing and lots of fun.
    Also known as reverse reverb, Inverse is characterised by a slow attack followed by an abrupt cutoff, combined with a repeat of the original signal. Overall length of the effect is controlled by the Size parameter (1‑32 metres in 32 steps). Predelay (0‑246ms) can also be fed back on itself to create repeated inverse echoes.
  • GATE
    Gate recreates the famous gated stone room effect first made popular in the '80s by Phil Collins. As with the Inverse algorithm, the Predelay can be fed back to provide repeated versions. Slope is used to vary the end level of the reverb tail, and the gate time ranges from 0.150‑390ms. Colouration is controlled both by gate time and HF Cutoff.
    The Chorus algorithm combines 6‑voice chorus with three separate delays. The first of these can achieve a creditable 1500ms, while the other two supply a nonetheless healthy 1000ms. Like the Multi‑Taps, these delays can be tempo‑driven by MIDI clock, but seem considerably easier to set up. An Echo Rhythm parameter lets you set the delays to specific note values (a chart is laid out in the manual to guide you) and HF Cut, chorus rate, feedback and diffusion controls complete the picture. Altogether a very versatile algorithm.

MIDI: Dynamic And Otherwise

Lexicon coined the phrase 'Dynamic MIDI' to describe how effects could be controlled using MIDI, as offered in their legendary PCM70. Basically, it means that any parameter can be assigned to a MIDI controller and thus altered in real time by a slider/wheel/pedal, or whatever. This controller information can also be recorded into a sequencer, providing automated sonic gymnastics otherwise impossible to perform. Today, many effects units offer this facility, and now Reflex has entered the MIDI power‑user league. The basic MIDI functions one expects are present, including program change reception, and dumping the registers (memories) either in bulk or one at a time. MIDI channels 1‑16 or Omni are recognised.

Each register can define up to four parameters, referred to as patches, each one assigned a controller. You can even have a single controller affecting multiple destinations or multiple controllers affecting one destination — the choice is yours. Assignment of these controllers is simple: select the required parameter (enter APM mode if necessary) press and hold the Parameter/Learn button, send the required MIDI message, and the assignment is complete. From there, you can go on to define the relationship of controller movement to parameter changes, and select positive or negative scaling — ie. parameter values increase with controller values, or vice‑versa.

MIDI note numbers can also be used as a control source, which is particularly effective when playing monophonic parts, where a reverb or delay can increase the higher up the keyboard you play. How about adding reverb to specific sounds within a pre‑mixed percussion setup? Simply assign individual sounds across the keyboard according to the amount of reverb required for them. Reflex works on a highest note priority — it takes the highest value of any simultaneous notes, so this trick works best when the percussion sounds are separate and not too closely spaced. If you place a dummy (blank) note at the 'dry' end of the keyboard, you can create manually gated reverb effects. All these creative possibilities are from just one assignment. One note about real‑time control: certain parameters (such as Room Size) mute the effect momentarily as they are altered, meaning that care must be taken to apply those changes at an appropriate point in the music. This same muting also occurs when changing programs.

The Reflex is compatible with existing LXP editing software, as well as Lexicon's own MRC remote programmer; these editors see the Reflex as an LXP1. However, there are some minor differences, namely a couple of parameter variations in the Chorus algorithm between the LXP1 and the Reflex, and the Resonator (not present on the LXP series) has to be edited via the LXP Chorus II editor.

A ring/sleeve/tip socket on the rear panel permits a suitable double footswitch to control effect bypass (also MIDI controllable) and to step through a pre‑determined sequence of effects, useful for live applications. This chain of presets is arrived at by 'clearing' or skipping unneeded effects in the list of 128 registers, and therefore relies on having the desired programs in some kind of consecutive numerical sequence in the first place. I can see what Lexicon have in mind here, but it entails spending time putting the correct effects into the correct sequence anyway... why not just dump and reload sounds one by one in order? Either way, it seems an inelegant solution to the problem.

I have one more niggle concerning the MIDI Out socket, which can also be switched to be MIDI Thru; however, some contrary individual decided that the best way to do this is with an internal jump plug, requiring the user to take the side off the unit to get at it. Absolutely no cigar for this little gem. What's the problem with either (a) a separate socket, (b) a combined Out/Thru socket, or (c) a simple switch? The back panel is hardly overcrowded, after all.


Any reservations felt about the Alex in terms of its limited editing are by and large voided on the Reflex. The range (not to mention the quality) of effects is excellent and should satisfy most applications. Anyone interested in the Dynamic MIDI aspects who also wants the Lexicon sound at a very nice price should re‑assess their studio budget immediately. Even if MIDI control is not important to you, the enhanced front panel editing takes the Alex concept that much further, making high class, customised effects just a few button pushes away.

Reflex Algorithms & Parameters


Hall Plate

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1 Decay1 Decay1 Negative Fbk1 Feedback
2 Predelay2 Predelay2 Depth2 Group Dly
3 FX Level3 FX Level3 FX Level3 FX Level
4 Bass Mult4 Bass Mult4 R Delay Fbk4 ‑‑
5 Hi Cut5 Hi Cut5 R Delay5 L Delay
6 Size6 Size6 Shape6 R Delay
7 Predelay Fbk7 Predelay Fbk7 L Delay Fbk7 ‑‑
8 Diffusion8 Diffusion8 L Delay8 Hi Cut
9 Reflection Level9 ‑‑9 Rate9 Diffusion
10 Reflection Delay10 ‑‑10 ‑‑10 Echo Rhythm
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1 Res Fbk1 Size1 Gate1 Feedback
2 Tuning2 Predelay2 Predelay2 Delay 1
3 FX Level3 FX Level3 FX Level3 FX Level
4 Predelay4 ‑‑4 ‑‑4 Hi Cut
5 Lo Cut5 Hi Cut5 Hi Cut5 Delay 2
6 Shimmer6 Slope6 Slope6 Delay 3
7 ‑‑7 Predelay Fbk7 Predelay Fbk7 ‑‑
8 Richness8 Diffusion8 Diffusion8 Diffusion
9 Slope9 ‑‑9 ‑‑9 Rate
10 ‑‑10 ‑‑10 ‑‑10 Echo Rhythm

Reflex Presets

Large Hall Rich PlateVocal Hall Drum PlatePiano Hall Vocal PlateMusic Club FlangerGuitar Stage ChorusSmall Room CanyonInverse Multi TapsGate Resonator


  • Superb quality reverbs.
  • Flexible editing.
  • Simple operation.
  • Versatile MIDI functions.


  • Multi‑Tap/MIDI clock settings confusing.
  • Internal Out/Thru jumper.


Very appealing, very affordable. Ideal both as a dedicated, classy reverb and for its additional effects.