IDSD Diablo-X
PORTABLE DAC| AMP | BLUTOOTH

Unadulterated performance

The Diablo-X focuses on pure unadulterated performance, meaning that much attention has been applied to the power supply circuitry.

Battery power provides ultra-clean and stable DC current avoiding the issues of mains electricity – dips, spikes and noise-inducing RFI/EMI pollution. BUT there are sonic downsides resulting from low output voltage and inconsistent output impedance as batteries discharge.

In order to make less efficient headphones, like planar magnetics, sing, the voltage needs to be stepped up from 3.7V to +/- 15V.We use a step-up converter running at 1.2MHz – a frequency far beyond audibility that is easier to filter than a typical switch-mode supply, enabling high linearity and ultra-low noise.

Unrivalled components

High-bandwidth power supply circuitry is dedicated to each critical part of the Diablo-X’s design, with independent linear regulation delivering excellent PSRR (Power Supply Rejection Ratio) performance.

The headphone amp stage eschews IC regulators in favour of Panasonic OS-CON capacitors, delivering 2320uF between them.

Even the USB input stage benefits from dedicated regulation and multi-stage filtering, and the microprocessor control circuitry (often a local source of digital noise) has separate regulation, too.

The devil is in the detail

Whether you are using your favourite IEMs/headphones or a pair of xMEMS compatible IEMs, the Diablo-X connections have you covered.

At the front of the unit, alongside a standard 6.3mm single-ended headphone socket, resides a 4.4mm Balanced output for headphones offering balanced connection.

At the back are two digital audio inputs: USB-A and a S/PDIF socket that accepts both electrical and optical signals, the former via a 3.5mm connector and the latter via a supplied adapter.

The USB-A input features a ‘male’ connector, rather than a typical ‘female’ port for greater mechanical integrity.A separate USB-C charging port is also provided, along with a 4.4mm Balanced output to connect to an external amp.

The XMOS 16-Core chip processes the audio data received via the USB* digital input.

This low-latency XMOS microcontroller has greatly enhanced processing power. Compared to the current generation of eight-core chips, this 16-core IC delivers double the clock speed (2000MIPS) and four times the memory (512KB), as well as the latest SuperSpeed USB standard.

iFi’s in-house digital development team has programmed the XMOS firmware to optimise sound quality and ensure a perfect partnership with the Burr-Brown DAC.

DirectDrive

An important aspect of the circuit design is its direct-coupled nature (no coupling capacitor is present), achieved without a conventionally applied DC servo.

DirectDrive® equals a direct signal path which means less signal degradation. This direct signal path is unequalled in audio and is the reason why the sound is so ‘true’.

‘Negative feedback’

‘Negative feedback’ is used in amplifier circuits to compare the output signal with the input signal and correct errors, in order to control gain and reduce distortion.

For sound quality, this is positive; BUT commonly applied, one-size-fits-all ‘global negative feedback’ can also highlight different problems at the same time as solving others – corruption of the error signal, phase shifts, group delay and so on can all have a negative impact on sound quality.

We recognised that different parts of a circuit benefit from specifically optimised feedback loops and have developed a negative feedback system that is much more accurate than the usual approach. This incorporates multiple feedback paths instead of a global loop, each path optimised for a particular function and working synergistically with the others to deliver optimal overall performance.

PureWave

Balanced, differential analogue circuit design has long been championed for its ability to reduce noise and cross-talk within the signal path by fully separating the left and right channels.

PureWave is a new, balanced, symmetrical dual-mono topology with short, direct signal paths. The name refers to the sonic purity it achieves thanks to exceptional linearity and infinitesimally low levels of noise and distortion.

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