Equalizer

The Electrodyne 511b is a feature-updated and greatly expanded version of the legendary 511 two-band discrete-transistor active inductor eq.
The 511b uses the same vintage design inductors, opamps and transformers as the 511 and original Electrodyne 711L eq from 1970.
Custom inductors and transformers are still made by the original manufacturer to strict factory tolerances as precise as 2% and high quality film capacitors are used throughout all eq circuits.
This allows consistent eq repeatability from channel to channel that was not possible in the 60's & 70's, as well as smooth performance and response from minimum to maximum gain at all frequencies that provides unusually musical sonic and tonal options, not experienced since the 1970,s.

New features:
-23 more eq selections than the 511 for a total of 36:
6 Peaking positions per band with standard and narrow bandwidth on each, plus one bonus frequency, for a total of 25 Peak selections.
6 Shelving positions per band, for a total of 12 Shelf selections.
-Stepped-gain pots with 1db steps from +/-1db to +/-6db, and unity-gain calibration trimmer for precision recall and mastering use.
-Special note:
The 511b includes all eq selections, curves and performance found on the 511, so 511 & 511b eqs can be used together as stereo matched pairs when set to the same Peak / Shelf, bandwidth and gain settings.

http://petesplaceaudio.com/electrodyne-music-equipment#511