M2Tech Joplin MkIII ADC/phono

For many, the proposal of an A/D converter in the audiophile field, also equipped with the functionality of a very high quality phono preamplifier, may seem like a gamble at the very least.

But the success encountered by the Joplin project, since 2011, in its various versions, has exceeded all expectations. In the latest MkIII release, the Joplin offers top-level performance and flexibility that meets any need.

The Joplin MkIII features a single-ended analog input with variable gain from 0dB to 65dB, powered by Burr-Brown PGA2500 microphone preamps. The input impedance can be adjusted seamlessly between 10 Ohm and 50 kOhm, in order to optimize interfacing with any type of cartridge, but also with line level sources such as reel-to-reel and cassette recorders, mixers, tuners. ..

The conversion section allows you to acquire and digitize PCM signals up to 384kHz sampling frequency and 32 bits. In anticipation of subsequent use on lower resolution media, it is possible to apply a reduction in resolution up to 16 bit and/or apply dithering.

The Joplin MkIII features S/PDIF, AES/EBU, Toslink and I2S (in PS Audio format) digital outputs. The latter is served by an SRC (sampling frequency converter) which allows you to have a PCM signal up to 768kHz or a DSD signal up to 256x.

An auxiliary S/PDIF input allows you to send a signal already in digital format to the Joplin. This signal is made available on all outputs and is also sent to the USB interface.

The latter works in asynchronous mode according to the UAC 2.0 standard (USB Audio Class) and is used to send the signal acquired from the A/D section or the one coming from the S/PDIF input to a computer.

The Joplin MkIII is equipped with a digital signal processing (DSP) section which is used for various purposes:

to implement one of the 27 available phono and tape equalization curves;
to apply a high-pass and/or low-pass filter to the signal, if necessary;
to apply the MPX filter when acquiring from an FM receiver.

The adjustable gain, the adjustable input impedance and the availability of equalization curves make it possible to directly connect a turntable to the Joplin MkIII, without the interposition of a phono preamp. The acquired signal can be sent to a computer via USB for recording or to the input of a DAC for real-time monitoring. This latest configuration (Joplin MkIII + DAC) creates an unusual phono preamp that can make analog enthusiasts cry foul, but which reserves pleasant surprises for the most enlightened audiophile.

The Joplin MkIII is provided with an infrared remote control that allows total control.