Daniel N. Flickinger introduced the first parametric equalizer in early 1971. His design leveraged the high performance op-amp of his own design, the 535 series (USPTO #3727896) to achieve filtering circuits that were before impossible. Flickinger's patent (USPTO #3752928) from early in 1971 showed the circuit topology that would come to dominate audio equalization until the present day, as well as the theoretical underpinnings of the elegant circuit. Instead of slide potentiometers working on individual bands of frequency, or rotary switches, Flickinger's circuit allowed completely arbitrary selection of frequency and cut/boost level in three overlapping bands over the entire audio spectrum. Six knobs on his early EQ's would control these sweepable filters. Up to six switches were incorporated to select shelving on the high and low bands, and bypassing for any unused band for the purest signal path. His original model boasts specifications that are seldom met today. [ citation needed ]
The TC-Helicon VoiceTone Mic Mechanic 2 is a compact pedal that's meant to fine tune and improve your vocals. It does away with fancy bells and whistles, and sticks to essentials like reverb, echo, pitch correction, and TC-Helicon's Adaptive Tone technology, which intelligently tweaks compression, EQ, de-essing and gating as you perform to improve the resulting sound. For more control over the ambience of your voice, the pedal offers a total of 8 reverb and echo presets, including variations of Room, Studio, Hall and Delay. All of these features are packed in a standard size all-metal stompbox that can run on a 9-volt battery, a pedalboard power supply or a DC adapter.
Jim Marshall didn't start out building great amps. In fact, his entry into the amp world came about in part because the drummers that visited his music shop for equipment and lessons often brought along their guitar players. Conversations about their amplification needs led to the birth of a line of amps that would eventually change the sound of music. From those first humble creations to Pete Townshend's first monster full stacks, from the mid-'60s combos to Hendrix to backlines of multiple Marshall rigs, one thing has remained constant: Marshall's commitment to the best tone and performance possible.