SparkoS Labs is announcing the development of its latest product, the SS Phono preamplifier. Andrew Sparks shares the development process and showcasing the design in its current state.
This is the raw unpopulated Phono Amplifier board which was fabricated by Circuits West (SparkoS Labs preferred PCB manufacturer) of Longmont, CO. We were able to take a tour of the factory lead by the president of Circuits West, Chuck Anderson to witness the PCB fabrication process. To visit the Circuits West website click the link below
Stage one…. Bringing up the power and testing of the raw power supply, AC input section, and the Toroidal Power Transformer. No smoke was observed, nor were any explosions had. Great Success!
The SS Phono amplifier will make use of the finest active devices available on planet earth – SparkoS Labs Discrete Op Amps and Discrete Voltage regulators. These discrete devices will be used in all of the Audio stages throughout the Phono Amp. Here is a close up of an SS3601 Single Discrete Op Amp used in the first stage.
And here we have a lone SparkoS Labs SS783.3 discrete voltage regulator used for powering the Microcontroller and digital section of the Phono Amp.
A close up of a couple of the SparkoS Labs SS3602 Dual Discrete Op Amps which are used in the 2nd and 3rd stages of the Phono Amp. These stages also implement the RIAA correction and use precision 1% tolerance Polypropylene Film capacitors (the large aqua colored caps) and precision 0.1% thin film resistors to achieve an RIAA accuracy of <0 .1db="" .="" div="">

An overall view of the main board, fully assembled. Mostly.
close up of the dsPIC33EP512 Microcontroller. The Microcontroller is responsible for controlling the front panel display, remembering the user settings, and driving the relays that are used to set various cartridge R and C loading, Gain, LF cutoff points, etc…
The Microcontroller is a 100 pin Thin Quad Flat Pack (TQFP), which exceeds Sparko’s hand soldering ability. As such, we called in the the experts at our preferred Electronic Assembly House, TRACER PCBA of Golden Colorado. A big thank you goes out to Cole of TRACER for helping with the installation and soldering of the Microcontroller onto the PCB. Sparko could have never done it without you. Tracer PCBA’s website can be found here –
The SS Phono amp will have 2 sets of RCA inputs to allow 2 turn tables (and a microphone!) to be plugged in simultaneously. Each input (Input 1 and Input 2) can have unique settings that will automatically get recalled upon changing the active turn table input. The output of the Phono Amp will be both RCA and XLR for maximum flexibility.
Testing the front panel Thin Film Transistor (TFT) Color display. Both the display background and the text on screen can have a user controlled 16 bit color assigned to it, yielding 4,294,967,296 (4.29 Billion, or 2^32) possible user adjustable display color schemes. Note that this count includes color schemes that are completely useless, like black text on black background.
The front panel touch screen allows the user to adjust all of the settings for both Input 1 and Input 2. All that is left to do now is to spruce up the graphics of the display such as putting a back arrow icon for the Back Button rather than simply having a button that reads “Back”. Stay tuned for that….
The First Order Ominously oversees prototype construction.
And finally we have Lutz. SparkoS Labs right hand dog who remains in the background, quietly running the show, calling the shots, and protecting everyone from the evils in the world; the things that geek. What ever would we do without him?