The LaChapell Audio Model 583s is the world’s first vacuum tube preamplifier designed for the 500 series format. Based on our popular 992EG, the 583s is quickly becoming the next must-have preamp for those looking to add that extra warmth and character to their “lunch box” collection found only within the thermionic realm. Our initial design approach was simple; identify and extract the key design elements of the 992EG that directly contributes to its’ sound signature, and then inject that into the 583s. This, of course, is the amplifier’s input stage, where the lion share of your signal’s quality and character is generated. While the 583s utilizes a more traditional single-ended amplifier configuration, the overall topology of the 583s’ microphone input stage is equal to that of the 992EG; specifically, feedback loop configuration, input transformer turns ratio, input impedance, capacitance, etc… Together with the CineMag CMOQ nickel alloy output transformer, the 583s also features an ultra clean output stage using premium Burr-Brown & THAT Corporation balanced line drivers.

The 583s comes with a few additional options. The standard microphone input transformer is the CineMag CMMI-10. However, users can specify the Jensen JT-115k (the very same used on the 992EG). Another exciting feature is its easy access to the tube, allowing the user the ability to utilize vintage premium tubes such as Telefunken, Mullard, RFT, Philips, or any other 12AX7/ECC83 variant!

The 583s is also built to be a “good neighbor” to your other 500 series modules. With the exception of the tube access opening, the 583s has an enclosed chassis, which helps direct cooling and prevents any unwanted interference. In operation, the user has individual control over the input and output gain stages via fully variable potentiometers. This, like its’ 992 older brother, provides total flexibility to explore the 583s’ broad sonic pallet, enhancing its versatility for your recording environment. Additional functions include four illuminated NKK toggle switches for 48v (Phantom), db input pad, polarity reverse and input select.

Featured Highlights:

True Vacuum Tube Amplifier

Fully Variable Input~Output Control

Robust Construction

Transformer-less Hi-Z Input

Premium Components

80% Nickel Output Transformer

Clean, Attractive Layout