Apex Speaker Cables

“Did they reduce RFI, EMI or maybe microphony too? What I do know is that until they arrived I had not encountered a product that claimed to deal with these negatives effectively, yet left musicality undamaged.”






Quiescent’s award-winning Apex ultra-low noise speaker cables deliver unparalleled clarity to any system, transforming an audio experience into such realism that it is the reference benchmark for industry reviewers.


The Quiescent Apex Speaker Cable is the ultimate in high-end speaker cabling. It can be used as a direct replacement for other cable looms or as part of our Peak Speaker Connection System as an upgrade to the Peak Speaker Cable.

Building on the knowledge gained over the last 25 years, our engineers re-evaluated our award-winning Vertex Moncayo to manage better the effects of electromagnetic interference on radio frequency propagation and the vibration transfer from the speakers into the electronics.

The result is the Apex ultra-low noise speaker cable.

B-ASC25SB (LR) 1 close up


Apex ultra-low noise speaker cables are used for single-wire connection and constructed from four 1.25mm solid-core silver conductors terminated with WBT nextgen™ silver 8mm spades or WBT nextgen™ silver 4mm banana plugs. 

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Whilst other manufacturers developed and launched premium speaker cables using expensive conductors and connectors, our Vertex Moncayo was the first speaker cable developed with a proper understanding of the two main factors affecting system electronics.

The first of these is the cascading of high-frequency standing waves that propagate in both directions along the length of the cable. Traditional decoupling techniques used in the DC to low frequency (1Hz to 100KHz) are ineffective at dealing with this noise due to impedance mismatches along the transmission line. Secondly, a speaker has been designed to mechanically vibrate the air, which is the sound we hear. Speaker manufacturers spend much time minimising vibration resonance in the cabinet to ensure that the drivers’ sounds are emitted correctly from the front and not absorbed or reflected from the cabinet itself. Equipment stand manufacturers and makers of equipment supports or cones have devised solutions to minimise the vibration going into our electronics from the air or floor. The issue we identified more than 20 years ago is that the single most effective conductor of this vibration is the speaker cable itself. A speaker sends large amounts of this vibration into the electronics, causing microphonic-generated noise.

In our first speaker cable, we developed the Moncayo module, which was an integral part of the module and used an absorption labyrinth to dissipate some of this RF energy into a matched load. It also absorbed the vibration transmitted through the speaker cable to minimise the amount the electronics receive. Our Hi-Rez Moncayo took this a step further, being the first Vertex product that included EMI/RFI tubing along the length of the cables. As described in the technology discussion on the Peak Speaker Module, the problems with the Moncayo were associated with usability and flexibility. Therefore, we developed the modular cable systems that are the basis of our mains and speaker cables in the Quiescent portfolio.

Whilst many manufacturers focus on signal conductivity, the Apex uses methods to control the propagation of the damaging electrical and mechanical oscillation transmitted along the length of the cable. A key design consideration was to use filtering strategies that do not interfere with or damage the musical signal in any way while ensuring that any unwanted noise is eradicated, providing superior performance. The Quiescent ultra-wideband, multi-phase filter is the culmination of our research, and it is so small that you wouldn’t even know it is there. The only indication of its presence is an improved audio experience overall.

Using twin 1.25mm solid silver conductors may seem over-engineered to carry current to the speakers. Our prime objective is to create an extremely low impedance path for noise to be transferred efficiently away from the power amplifier. Deployed with the Peak Speaker Modules, the speaker cable becomes a highly efficient high-frequency impedance-matched load with high return loss over a wide band. Whilst traditional audio engineers will tell you that ultra high-frequency waves are unimportant, they do not understand that these standing waves modulate with the musical signal, damaging important phase information and other artefacts of the musical signal. This effect can be heard as a lack of a three-dimensional soundstage (or flat and kept within the speakers) and perceived distortion of certain mid-band and high-frequency notes.

Another important characteristic of all our cables is that we use conductors threaded through a Teflon™ air tube, ensuring that cable capacitance is incredibly low. This means that the signal’s time domain, as sent to the speaker, undergoes very little phase change, and the music heard has a wider soundstage with improved perceived forward and back presentation. The cores in their air dielectric are threaded into our proprietary EMI absorbing sheath and finally into a braiding with very low acoustic transmission properties.

With all this attention to detail and manufacture, the Apex speaker cables have an extremely low noise floor with a high transient current carrying capability, improving musicality, bass propulsion, and tonal accuracy way beyond that reached by others.



Twin 1.25mm 99.9%  solid-core silver conductors for high transient current carrying capability


WBT nextgen silver 8mm spades

WBT nextgen silver 4mm banana plugs 


Conductors fed into Teflon™ air-tube insulation and Quiescent proprietary EMI/RFI absorption tubing for low noise

Outer Covering

ABS acoustically damped braiding


0.5m increments up to a maximum 5m per cable