audio equipment design and manufacture


NonLinearAudio™ products



FlexiGuy (FG500) - Mic/Line/Instrument Preamplifier:


The Flexiguy microphone/line/direct inject (D.I.) preamplifier offers up detailed and flexible tone, useful and controlled harmonic contribution and a somewhat "tape-like" dynamic response.

Useful Every Day

FG500 Flexiguy product page

FG500 Flexiguy pdf "cutsheet"

sold out - available on a BTO basis (info) ((571) 304-7279)

CurvOmatic (FT501) - Resonant LP / HP Filter Set with Bax Tone Tipper:

Ft501 CurvOmatic

The CurvOmatic module is a versatile set of high and low pass variable resonance sweep filters combined with a very sweet sounding version of Peter J. Baxandall's classic 1950 tone control circuit.

Used in combination, the resonant filters and Spectral Tone Tipper provide a surprising amount of tone carving and shaping capability that is unlike anything you can get from standard equalizers and cutoff filters.

Unusually Curvy

FT501 CurvOmatic product page

FT501 CurvOmatic curve plots

FT501 CurvOmatic pdf "cutsheet"

available OTS (info) (inquire)

Blenda (PLP502) - Parallel Loop Processor:


Blenda enables classic parallel processing in a "500" module. Blenda provides selectable level-shifted and impedance-adjusted loop interface modes to match to pedals, synth and hi-fi devices. Three loop modes accommodate balanced or unbalanced signals, matching the operating level and impedance to a variety of different equipment, including effects pedals and electronic instruments, as well as traditional outboard gear.

Blenda provides the functionality and signal path of a premium analog studio mixer and adds optimization of level and impedance of the effects insert loop to match to pedals, synth and hi-fi devices... a feature that no studio console we know of incorporates.

"it's da BOM NOM!" ... blend-O-matic null-O-matic

PLP502 Blenda product page

PLP502 Blenda pdf "cutsheet"

in production - soon come (info) (7654585939)

isolator (i3r101) - 3-band DJ Isolator:

(450) 362-2181

The Isolator i3r was developed to bring high fidelity to the rotary DJ experience. Crafted with utmost attention to sonic character, the Isolator proves itself to be a studio-grade isolating EQ device that can be used in a variety of applications.

The Isolator is a 24dB per octave three-band stereo isolating equalizer with cutoff frequencies at 300Hz and 3kHz. It is inherently a performance tool made for those who want the classic rotary isolator experience with updated, low-distortion circuitry and the no-maintenance reliability of a brand new boutique device. Use this in the club or try it out in the studio for critical mixing or mastering applications.



currently made to order (email)


About's not about making another rendition or clone of a common "classic". It's about making truly useful creative analog audio hardware tools with purpose.

NonLinearAudio™ is the outgrowth of creative technical audio design concepts and efforts from Jens Jungkurth (Eisen Audio, LLC) and John Klett (polka mazurka).

NonLinearAudio™ staff is comprised of audio engineers, who use their ears as well as math and measurement, while consulting other seasoned recording engineers producers and musicians for end-user feedback.

NonLinearAudio™ products are designed and assembled in New York City, U.S.A., using high quality, carefully selected, domestically-produced materials wherever possible and practical.


all site content copyright nonlinearaudio llc, jens jungkurth and/or john klett 2011-2018