A short film about the ISONOE ISO420 DJ mixer

Where’s the bottleneck? Vinyl-spinning DJs will almost always point the finger at the mixer. Its internal circuit is built to a price point to primarily satisfy the business modelling of the likes of Pioneer, Allen & Heath, Behringer, Numark et al. Thems the breaks with many of the bigger manufacturers.

Bringing a more audiophile approach to DJ mixer design is one Justin Greenslade whose company ISONOE cuts its teeth on Technics turntable isolation feet before turning its hand to bespoke electronics for third parties. One such caller was electronic music producer/DJ Sam Shepherd (aka Floating Points) who wanted the DJ mixer bottleneck eradicated — a collaboration that in 2014 birthed the ISONOE-designed FP mixer.

From the ISONOE website: “It was designed and manufactured from the ground up over a 4 year period. All circuitry is single-ended class A and built exclusively from discrete transistors, with no class A/B stages or integrated circuits whatsoever in the path. Its mechanical construction is of equal calibre to the circuitry, with all electronics being shielded by twin layers of alloy and steel.”

Greenslade also had a hand in bespoke mixers for Dixon and London listening bar Spiritland.

In bringing a more generalised version – the ISO420 – to market, Greenslade heeded collaborator James Murphy’s insistence that the final design should be no larger than a vinyl record so that it could fit into a record case. Inside its 12″ x 12″ chassis, our Londoner applied the same attention to detail with circuit design and component matching for an output that registers “0.00033% THD+Noise”.

According to Greenslade, the handmade ISO420 offers the same measured performance as audiophile-aimed pre-amplifiers selling for similar cash – two and a half thousand British pounds – but also offers 3 x single-ended inputs (switchable between line level and dual-mono MM phono), 1 x balanced inputs, balanced outputs, low distortion EQ, Lundahl output transformers, ALPS pots, VU meters and a pair of headphone outputs (one front, one back). An all-in-one powerhouse for anyone willing to think beyond the hi-fi world. You can get busy with specifications here.

Hard Wax main man Mark Ernestus recently put an ISO420 between a pair of Technics in his Berlin record store to create the perfect intersection of DJ culture and audiophile obsession. What better place to talk to Justin Greenslade about his work?

Further information: ISONOE