March 18, 2023

Current Pedal Obsession: ZCat Big Reverb .

It’s simply ambient.

Reverb pedals have become complex with octaves and filters and effects—oh my. Wouldn’t it be nice to have a reverb that’s goes from plate-like to gorgeous cosmic clouds with a simple crank of the Decay knob? Well, here it is: The ZCat Big Reverb

Around for over a decade, this little box from Latvia is an early atmospheric reverb that’s undeservedly remained under the radar. It has just one primo algorithm that sounds like a plate reverb with the Decay knob at 7a and the celestial heavens opening up at 5p. The decay maxes out at an astounding 30-seconds, but can be sustained infinitely (like a freeze pedal to play over) by holding the footswitch until the LED flickers.

How does it sound?

The Big is cloudy with a 100% chance of slow modulation. It’s not exceptionally wet or dusty. It has more mass than most ambient reverbs, but it’s still very musical and can nicely lay behind your dry signal. There’s no control for the speed of the modulation, but the movement is smooth and present, without sounding like any particular type of modulation or overwhelming the space. Bottom line: Big can hugely enhance your dry without dominating. It seems to sound just right at every decay setting and it blends well with every delay I’ve tried before it.

The demo audio above goes through the Decay knob (7a, 10a, 2p, 5p) with a Beat Root Multiscale tongue drum. No other effects were used. For the first half of the demo, I’ve kept the Big at a usable level so you can hear one of its best features: just how well it blends with the dry. As a matter of fact, Big can be blended so it seems to soften the dry, smoothing some of the harshness of the attack if needed. It can be useful for tenderizing the abruptness of delays or glitch pedals before it. (Or for emphasizing them if you put them afterward.) For the second half of demo, I turn it up to 100% wet, since the glorious cloud it creates can be a useful effect on its own.

One knob to rule the mall?

Decay knobs on reverbs traditionally increase room size. But ZCat Big’s Decay knob does much more. Consider it six well-tuned knobs in one. Here’s what it affects:

  • Space From a plate to a universe. While built for ambience, settings in the 7a-9a range create some intimate and natural-sounding spaces.
  • Attack The reverb itself never comes in harsh, it starts slightly softened at 7a and extends to a fade-in at 5p. The volume level of the swell can be set so it fits naturally into the mix. At 100% wet, It blooms-in clouds of joy.
  • Swell It gets slower as you crank.
  • Modulation It wisely gets more noticeable and add movement to longer decays.
  • Fidelity Probably just the nature of the reverb lingering long enough to notice the highs and lows, but the Big seem to know when to add a little extra rumble or twinkle on longer decays.
  • Complexity Again, it might just be the nature of the trails sustaining long enough to hear, but there’s more complexity to the reverb on longer decays.

Though the ZCat Big Reverb creates an unnaturally large space, it always sounds good with very a natural-feeling decay, no matter where you set the knob. The other two knobs make the Big fit well in most board scenarios: The Volume knob can give the output a modest boost and the Mix knob effectively gives you kill dry at max, so Big works solidly in a parallel effects loop.

Acoustic response.

The Big has no tone control. But a really nice thing is that it adds has no color of its own and responds well to touch on string instruments. The reverb gets amplified by your playing, so the harder you play, the exponentially louder it gets. The tone created from plucking the strings with a pick, nails or skin and pluck-hand position between bridge and neck will be reflected in the reverb. So when technique brings out the brightness of the strings you’ll get added treble and when it brings out the mellowness of the strings you’ll get added bass. This makes Big a practical reverb for acoustic instruments or for clean electric players. (Not that it’s not great with distortion.) I’d recommend you spend some time with Big without any other effects on to understand just how much it can do for your sound by itself.

Trails and Hold modes.

There are 4 mode settings controlled by holding the footswitch on powerup. Release after:

  • One flash: true bypass, no trails, hold disabled
  • Two flashes: buffered bypass, momentary hold function with trails, when released, reverb goes off.
  • Three flashes: buffered bypass, latch hold function with trails, when latch is off the pedal/reverb is still on
  • Four flashes: buffered bypass, latch hold function with trails, when latch is off the pedal/reverb is off

Hold on for a minute. Or an hour.

Something clever that Vlad at ZCat did was create a hold mode that acts like a freeze pedal. (Recently we’ve seen this as a feature of newer ambient reverbs.) When you hold the footswitch the reverb sustains and stops receiving input. So you can use it to both fill in a pause in your playing or as a pad to play over top of. The sound of the freeze will vary, depending on where you lock it down. You can also choose Trails mode to let the reverb fade out while you’re still playing. Note that during hold, that what you play overtop will not have reverb. It can be useful to have a short delay before or after Big to restore some ambience to the dry while playing over a pad.

When setting the mode, try releasing the footswitch after three blinks. This sets the reverb to return to normal decay when you disengage Infinite mode as well as trails so it fades when you turn off the reverb. In this mode the Mix knob becomes inactive. A nice trick is to set the mix 100% wet for starting with a swell of just the reverb and then engaging hold so the dry comes back in overtop.

My take.

I’ve read in forums of players who gave up their complicated large reverb pedals for the good-ol’ ZCat Big. I’m thinking the reason is they like the perfectly pliable sound as well as the lack of complexity: Big lets you get lost in the clouds, not lost in a bunch of knobs. With those overly complex reverb pedals out there you have to question: how many of those programs and knobs do you really use? On those, I’ve found myself gravitating to one setting and just leaving it there. I particularly like the decay knob on the Big at about 2p. The reverb gently swells in and hangs onto the note like a quiet, automatic freeze.

The Big is huge, but not ferocious. Expansive, but not overbearing. A touch dark and twinkly at the same time, but not octave or shimmer. And it always seems to add a transparent magic to pedals before it. Just having one exceptional and flexible algorithm, a decay knob, the ability to go 100% wet and an infinite footswitch really covers most of the reverb territory I need.

For the spectators: Spin FV1 chip, 90mA, trails/true bypass, mix to 100% wet, stereo version available

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