The Neunaber Immerse Reverberator provides an impressive selection of accurate, believable, and totally gorgeous simulations of real acoustic spaces, as well as classic studio plates and other old analog favorites. It offers fresh, distinctive tones that make me want to bury everything I do in a rich, three-dimensional ambient wash, with the sound quality of the finest pro-audio digital reverb units in a compact format.
It has eight of the company’s finest stereo reverbs, including its much lauded Wet and Shimmer (A and B) settings, in one very compact and easy to use stompbox. The Immerse also has all the usual hall, plate, and spring settings as well, and a pair of settings that combine the Wet mode with echo, and with a lush, chorus-like detuned modulation. ​

The Neunaber's Wet algorithm is unique and has a US patent. Although the company’s website and the unit’s included instruction sheet don’t specify what type of reverb it’s pumping out, it sounds to me like a hall emulation. But the Wet setting also sounds really good when you turn depth way down for a rockabilly-style slapback, or dial it somewhere in the middle to use as a pristine set-and-forget reverb. And the tone knob lets you tailor the ambience from a darker, more muted vibe to something more akin to a live room with hard reflective surfaces.
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Both Shimmer A and Shimmer B consist in a series of overtones that trail along with the decaying reverb, and almost resembles a keyboard pad – Neunaber call this effect “choir of angels”. Shimmer creates a multi- dimensional illusion of massed high- pitched strings behind your tone. Basically, it is a Wet reverb, that can have variable amounts of shimmer added to the effect - the shimmer being created by an octave pitch transposer, delay and filter. The Tone knob on Shimmer A adjusts the tone of the effect. The Tone knob on Shimmer B adjusts the filter selectivity, creating a "breathier" sound when turned up.

It offers extensive control over blending, tonal response, and many other parameters, including external switches for Kill Dry, which engages 100 percent wet effects and removes the dry signal, and Trails, which allows reverb to decay natural when pedal is bypassed - in off-position it instantly cuts off decay when pedal is bypassed. 
Your dry signal stays analogue while digital processing is going on around it, but there’s no true bypass. 

The Immerse Reverberator features a high-quality buffered bypass to optimize and restore sound quality, which is especially useful as most guitarists place reverb pedals at the end of the signal chain directly before the amp’s input.
All of its ins and outs can be used in mono or stereo operation. 
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