KURZWEIL Rumour and Mangler

Kurzweil's Rumour and Mangler are two sibling stereo-effects processors that, despite their twinlike appearance, have a fraternal rather than an identical
Publish date:
Social count:
Kurzweil's Rumour and Mangler are two sibling stereo-effects processors that, despite their twinlike appearance, have a fraternal rather than an identical

Kurzweil's Rumour and Mangler are two sibling stereo-effects processors that, despite their twinlike appearance, have a fraternal rather than an identical kinship (see Fig. 1). Although both are multi-effects units and have some degree of overlap, the primary function of each unit is distinct from the other. Rumour's main focus is on ambience, reverb, and other time-based processing such as delay and chorus. In addition to a few reverb and delay algorithms, Mangler emphasizes effects such as amp simulation and -distortion, bit crushing, rotary speaker, phasing, and compression.

Based on the architecture and DSP chip of Kurzweil's flagship processor, the KSP8 (reviewed in the February 2003 issue of EM), Rumour and Mangler offer the project-studio user access to some of the power and sound quality of their predecessor at a reasonable price. The sound quality of both units is good, attributable to 24-bit conversion, 128× oversampling, and KDFX algorithms ported over from the KSP8 — the same algorithms that are found in the K2500 and K2600 processors.


Aside from some minor cosmetic differences, the units are physically identical. Each occupies a single rackspace and features stereo-balanced analog I/O on ¼-inch TRS connectors in addition to S/PDIF digital I/O on RCA connectors (see Fig. 2). Each also has MIDI In and Out/Thru ports and a ¼-inch footswitch jack. The power input is a nonlocking minicoaxial plug typical of low-voltage devices.

The nonlocking power connection is a minor disappointment because it can become easily disconnected if the cable is not well secured. The power supply is the lump-in-the-line type, which is preferable to a wall wart. You can select the MIDI Out/Thru port's function using a switch on either unit's rear panel; that might be a problem if you don't have easy access to the back of your rack and need to frequently change the port's status. A switch to specify a -10 dB or +4 dB output level is also on the rear panel. The switch's location in this case is less of a drawback, because you're less likely to need to change operating levels once you've set up the unit.

The front panels are laid out ergonomically, striking a good balance of tactile and visual elements including dedicated buttons, control knobs, metering, LED display, and a data wheel. On the left side are knobs to adjust input- and output levels and a 3-segment LED input-level meter. (I would prefer more detailed metering, but this seems to be standard for devices at this price.) Four buttons are dedicated to Bypass, EQ, Tempo Tap, and accessing the Master edit menu. The 2-by-20-character LED display shows the program name and number, the active parameter value, and the effects algorithm. I appreciated the dedicated contrast control on the front panel, which was easy to adjust without having to dig through pages of menus.

The detented Bank knob lets you select from 12 factory banks and 4 user banks. The Preset knob lets you select one of each bank's 16 presets, for a total of 256 programs. The Load and Store buttons are adjacent. On the right side of the unit are a Parameter Select knob and a big Parameter Value wheel that has a depression for your fingertip, allowing for rapid twirling. The lack of a power button makes me uneasy, but I can soothe that sensation by plugging the units into a power strip that I can readily turn on and off.


Both units have a programmable, defeatable, global 3-band EQ that's positioned pre-effects. Because effects are often overly bright and I prefer a slightly darker effected sound, I like adding EQ to the signal coming back into the mix bus though an aux return. Although you can't switch the EQ to post-effects, it still offers control over the overall sound.

The Rumour and Mangler follow or generate MIDI Clock, or you can access the tempo-tap function using the dedicated front-panel button or a footswitch. As an alternative to using a sequencer's tempo map to achieve a more human feel, I like being able to control beat-synced delays and other effects manually. The sampling-rate clock can be synced internally or externally, and you can use either box in the digital domain as master or as slave.

Another handy feature is a selectable global Wet/Dry mode. In addition to the output being fully wet, you can set up either unit to run in Insert mode, in which the wet/dry mix is saved with the effects program. That capability is useful if you lack the proper busing or routing that is necessary to use the effects in a send/return configuration.

One small complaint I have about Rumour and Mangler is that when you reach the last item in a parameter menu while editing, the list does not wrap around. Consequently, you must scroll backwards to get back to the beginning. My experience in shaping an effect is that because so many parameters interact with one another, I like to make a few passes through all of them fairly quickly to get things dialed in; reaching a dead end slightly interrupted my work flow.

Rumour and Mangler's MIDI implementations are extensive, and MIDI control is easy to set up. For each algorithm, the most commonly used parameters are set by default to Control Change numbers 1 through 16. I simply plugged in my Oxygen 8's MIDI Out to the Mangler's MIDI In, and I could tweak basic parameters quickly and easily. More extensive MIDI control is available, and you can back up settings by SysEx. Firmware updates, when they're available, will also be loaded using MIDI.


Rumour and Mangler have some degree of overlap, as can be expected in most pairs of multi-effects processors. What distinguishes one processor from the other is each unit's primary focus.

Rumour is mainly an ambience and reverb unit with some additional effects included as part of the algorithms. At first glance, you might think that Rumour offers less bang for the buck because it has fewer effects types than Mangler, but Kurzweil has made a conscious choice to deliver quality over quantity. Proper ambience simulation requires significant DSP resources, and Rumour puts its processing power to good use.

The reverbs are thick and spacious, with good density, pleasant smoothness, and fine detail in the final decay or tail. As is often the case with factory presets, some of the settings are a bit heavy handed, but that's no problem. Such presets impart an instant impression of the effect, and they function well as a point of departure for tweaking to suit your own tastes or applications. I liked the beefy quality of the low-midrange in particular; still, you might want to make adjustments to the global EQ or to the program itself.

The ambience programs were subtle and tasteful. I used the Add Ambience preset to glue some overdubbed, close-miked keyboard parts together with a live vocal and acoustic-guitar performance that had a fair amount of room sound on it. I was pleased with the sound of the effect, as it was apparent in an almost subliminal way, but I definitely missed the effect when I bypassed it. The realistic nature of Rumour's effects should be helpful in a post-production environment in which Foley, ADR, and other nonproduction elements need to be blended in with ambient location recordings.

A reverb category called LaserVerb is fun, but it can be a bit much if used excessively. LaserVerb produces a chorused sound with a fair amount of movement in the stereo field. The effect works well on keyboards, guitars, and even backing vocals, and it's also well suited for horns and strings in urban, pop, rock, or electronic music styles.


Mangler has a lot to offer in terms of variety and quality. It has more of a wild side when compared with its subtler sibling. In addition to the standard chorus, delay, flanger, and phaser, Mangler has LaserVerb, rotary speaker, compression, distortion, and filter effects.

One preset that I particularly enjoyed was Clean Rotors Fast, which I applied to a real Rhodes keyboard part. It had the fun, swirly effect of sticking your face into a rotary speaker enclosure without the danger of getting the tip of your nose lopped off by a spinning speaker horn. Another useful preset was Tube Dist+Reverb, which sounded more like a stompbox than an overdriven tube amp, but in a good way. I used it on a meaty synth bass patch and on some drum loops with equally crunchy and savory results.

I was admittedly dubious about the quality of the compressor. I dialed up a few presets, and it sounded good on lead vocals and drums. Then I adjusted the threshold and other settings so the compression was fairly extreme, and I had to really push it hard to make it sound bad. You might argue that the compressor sounds a bit too clean, but I think that's a plus. You could grunge it up with some of the internal effects, or you could use a dedicated compressor if you need a specific sound. Overall, the compression is very usable, and I wouldn't hesitate to put it on individual high-profile tracks, across a bus, or on a full mix.

None of Mangler's effects banks were disappointing. All of the effects sounded good, and most were functional if not downright fun, with a minimal number of klunkers or filler presets.

Nonetheless, I was baffled by the high noise level in the distortion algorithms. Perhaps such noise is intentional for the sake of realism, or maybe it's just a necessary byproduct. Luckily, all of the guitar-oriented presets include a gate to control noise.


Rumour and Mangler are solid contenders in the crowded less-than-$1,000 hardware-effects category. Their sound quality is high, and the units are easy to use. They offer a nice combination of simple, accessible MIDI control with more extensive implementation and deeper editing. Browsing and editing the effects is quick, easy, and fun. The printed documentation is sparse, but it's sufficient and nicely laid out, providing a quick-start guide at the beginning. You can download more extensive documentation of the effects algorithms from Kurzweil's Web site.

Both devices are attractive although they are slightly pseudo-retro. They appear to be well built and have a solid feel to them. I wish they offered more onboard storage for user banks, but I suppose that might up their price. Kurzweil has done an admirable job of putting two well-balanced packages together.

Kerry Roseis an avid snacker and a lover of many delicious and exotic-sounding treats. He can be caught cooking up a sonic smorgasbord atkerry@edibleaudio.com.

Rumour and Mangler Specifications

Analog Inputs(2) ¼" TRS (balanced/unbalanced)Audio Outputs(2) ¼" TRS (balanced/unbalanced)Digital I/Ocoaxial S/PDIF (RCA)Word Length16, 20, or 24 bitsFactory ROM/User RAM Programs192/64MIDI I/O(1) In, (1) Out/Thru (switchable)A/D/A Converters24-bit, 128X oversamplingMaximum Input Level+22 dBuFrequency Response20 Hz-20 kHz, ±0.1 dBDynamic Range> 106 dB unweighted @ 1 kHzCrosstalk< -104 dB @ 1 kHz, +21 dBuTHD+ Noise < 0.001% @ 1 kHz, +19 dBuDisplay2×20-character LEDDimensions1U × 8.1" (D)Weight5 lbs.



Rumour and Mangler rackmount effects processors $649 each


PROS: Great sound quality. Easy to use. Extensive MIDI implementation.

CONS: No power switch. Flimsy power connection. EQ unable to switch to post-effect.


Kurzweil Music Systems/A N D Music Corp. (distributor)
tel.: (626) 964-4700
Web: www.kurzweilmusicsystems.com