500DT Dual Topology Preamp

The LaChapell 500DT dual topology preamp is a 500 series microphone preamp that features two separate topologies or amplification paths for unprecedented versatility and value for project studios, home studios, or professional recording studios. The 500DT is both a tube mic preamp and a solid state preamp in one 500 series module. When the blend knob is fully to the tube preamp side, the signal will pass through a custom transformer before being amplified by a TrueTube powered 12AX7 vacuum tube.

TrueTube is LaChapell Audio’s proprietary method of supplying a full 250V to the vacuum tube so you get loads of vintage clean tube gain (or drive it a bit harder to get some grit and bite). When the blend knob is turned fully to the opamp side, the signal passes directly to a solid state microphone preamplifier. This input is transformerless and will provide clean gain with exceptionally low noise. Placing the blend control anywhere between the two extremes will “blend” the two topologies for a near infinite variety of tonal options.

Vacuum tube and solid state preamp
Two mic preamps in one. With both a Truetube powered full sized 12AX7 vacuum tube preamp and a solid state preamp, the 500DT Dual Topology preamp is exceptionally versatile. Blend between the tube and solid state sides to mix the two sounds.

500 Series mic preamp
An extremely versatile tube and solid state mic preamp in the 500 series format based on the legendary 583S priced for project studios, home studios, and value conscious professional recording studios.

Trubtube 250V power
TrueTube technology supplies both the plate and filament of the 12AX7 vacuum tube with the proper voltages they need to access the full characteristics of the tube. Other tube preamp designs cannot supply the needed 250V and don’t have the headroom or harmonics that characterize that classic tube sound.

Front panel Hi-Z input
The front panel Hi-Z input allows the 500DT to be used as an instrument preamplifier. When a 1/4″ jack is inserted into the Hi-Z input, the 500DT switches into instrument mode, bypassing the input transformer so the instrument accesses the preamp directly.

Dual gain knobs
The Dual Drive knobs on the LaChapell 500DT provide an incredible array of tonal options. Increasing the input gain will drive the input stage harder, resulting in more tube harmonics when using the tube preamp side of the dual topology (and even some distortion if thats what you’re after). An emphasis on the output knob cleans up the signal for high headroom and clean tones.

Blend knob
The blend knob lets you go full vacuum tube, or full solid state. Get that rich harmonic warmth that only a properly powered tube can provide, or pristine cleans from the solid state side. Or… blend the two for the ultimate in versatility for your project studio, home or professional studio.