The envelope filter is a criminally under looked effect. Maybe that’s because at a certain time it was used to generate tones akin to twanging a rubber band, and that’s not always musically appropriate. But sometimes it is, and there’s a lot more you can do with the effect than that. Robert Keeley’s Neutrino Envelope Filter is designed to give you all sorts of different angles on the envelope filter and auto wah sound.
If you’re unfamiliar with this effect, it’s triggered by how hard you pick, and can give you automatic wah-wah sounds or something altogether different. More of a ‘bwah-bwah’ or ‘qwow-qwow’ sound than a ‘wah-wah,’ depending on how you set it. Keeley uses the classic opto-coupler design for depth and warmth, and has built in plenty of control. The Gain control lets you set the input level to get the best response to your picking strength. The Peak control lets you set how bright or dark the effect is, from deep and bassy to shrill. The Filter Selector is a three-way selector knob that lets you choose between three different types of filters. There’s also a Range switch, which lets you emphasise either the high or low frequencies. There’s also a Direction switch on the side that controls whether the wah-wah sound goes up or down (like pressing the wah-wah pedal down on each single strike, or up on each single strike). Oh and the graphic design is really great, with easy-to-see controls and a cool blue/magenta graphic over a white box. The ‘effect on’ indictor LED is nice and bright and the switch feels satisfyingly clicky.
OUT WITH THE OLD, IN WITH THE NEUTRINO
Plug this baby into a clean channel and you’ll get all sorts of great tones, from ‘quacky’ and edgy to big, fat and ‘gloopy’. Y’know those great old ‘home organ’ tones? This can get that out of your guitar no problem. Want a funky, scratchy, treble-heavy tone? That’s in here. But unlike some envelope filters, which seem to put uneccessary stress on your amp’s preamp when the signal hits its peaks, this one seems contained and slightly compressed, which keeps it from getting out of control. You can coax some utterly robotic sounds that are almost talkbox-like. You can go from Jerry Cantrell to Jerry Garcia with ease.
Try it with overdrive or distortion and you’ll get some truly wild sounds that might remind you of, say, The Prodigy synth sounds. It can sound organic or synthetic depending on where you put it in the signal chain. The ability to select between up and down modes is a huge asset to an envelope filter and although there are some others that have this, it’s kinda amazing that it’s not a standard feature on all of them, as ubiquitous as a ‘rate’ control on a chorus pedal. In the case of this one, it’s perfectly implemented and voiced. It’s especially useful with big fat overdriven guitar tones, where you can create a great backwards-feeling ‘shoolp’ sound.
PASS ME THE ENVELOPE PLEASE… AND THE WINNER IS…
This can be a pretty wild effect, and although it creates some amazing sounds in its own right, it really comes to life when you combine it with other effects. Combine it with heavy reverb or delay for really fat harmonics, or feed a wah-wah or tremolo into it for something truly exaggerated. Its utility is limited only by your imagination.
Hits and Misses
Deceptively flexible controls.
Very useful up/down switch.
None. The perfect envelope filter!