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ESP P05-Mini+P06+P99 - Phono Preamp

Given I still have a good quality direct drive turntable with a high quality cartridge and hundreds of vinyl records, the ESP P06 Hi-Fi Phono Preamp (RIAA Equalization) seemed like a great project. I purchased the P06 board (along with the P99 Subsonic Filter for Phono preamps and P05-mini power supply) from ESP back in February of 2018, then spring came and I shelved the project until now (Winter 2018/19).

I found a case on eBay for $38 US, and started my layout. Given the size of the case and height of the transformer and boards, I discovered I could mount all components on a piece of Plexiglas (acrylic sheet), eliminating a lot of drilling into the case. This type of construction allows for easy mounting, and a rework if needed (the acrylic sheet is less than ~$4.00 US).

The schematic below is a modified combination of the Phono Preamp (ESP P06) and the Subsonic Filter (ESP P99) from Elliott Sound Products. I like to experiment, so for the first test, the coupling capacitor C5 (P06) has been eliminated (C104 will block any DC from the phono preamp). To simplify the design, I’m testing if only one 18dB/octave filter will suffice to eliminate turntable rumble. The input resistor R103 (P99) has also been eliminated given it would be in parallel with R9 (P06). A cartridge loading capacitor as also been added to the input, the manufacture states a 47K ohm load with 100 - 200pF capacitance (just giving it a try for test 1).
Note: The original schematics are the intellectual property of Rod Elliott (copyright 1999 & 2003), and are used here by permission from Elliott Sound Products. Reproduction or re-publication by any means whatsoever, whether electronic, mechanical or electro- mechanical, is strictly prohibited under International Copyright laws.
I started the project by first laying out the back of the case. I needed to mount the line fuse, power switch, input and output RCA plugs, AC power cord, plus a hole to Tap & Die the ground screw. Here is a picture of the back of the case during drilling…
Back panel with components mounted
Acrylic sheet with transformer and ESP P05-Mini Power Supply board mounted
First layout: all internal components
Plug install, used AMP-100 gold plated for the input and outputs, standard for power
Jumper wires installed, and mounting to base
Final assembly and test

Conclusion:

Like all ESP projects, this one did not disappoint. The build instructions and schematics make construction straight forward. As with my other ESP project, the sound from this simple design was outstanding. The noise level is extremely low, and the 18dB/octave filter removes turntable rumble. Putting on an old LP and giving it a listen was a joy, the sound from this preamp is non-colorizing and clean.