As QED’s brand manager, Jack Fox oversees commercial operations and marketing as well as product development. Before joining the QED team, Jack Fox principally worked in both the public and private sectors of the commercial and product development domains, often with a connection to the world of sound.
Can you introduce us to QED?
QED is a UK company based to the west of London and is one of the longest-standing cable and accessory brands. We were established in 1973 by our founder Bob Abraham and became world renowned with the launch of the world’s first specialist speaker cables, QED 42 and 79 strand in the mid 70’s, both of which are still within the range today. Our philosophy is ‘The Sound of Science’ and our approach to the design and engineering of cables is very scientific ensuring that everything we say on the packaging of our product is proven with scientific grounding. We aren’t interested in marketing ‘smoke and mirrors’; we are interested in ‘fact not fiction’ and our mission is to use science to produce accessories that enhance the performance and sound of your system.
Why are speaker cables important?
Speaker cables are vital because the electrical relationship between your amplifier and your speakers is directly controlled by the speaker cable. In the mid 90’s we conducted the world’s most extensive ever investigation into this relationship called the ‘Genesis Report’ which is available on our website to download. One of the factors we discuss is the ‘resistance’ which directly controls the rigidity of the speaker’s drive unit, called the ‘damping factor’. This is why some speaker cables have a very firm, tight and controlled bass and some have a very loose, distorted bass because the speaker cable is not efficiently using the amplifier’s electrical signal and controlling the speaker’s drivers. I have heard some very expensive systems made to sound dull and lifeless and just outright bad by using bad speaker cables and as soon as you switch them to QED, the change is astonishing! As I always say, you wouldn’t buy a high performance sports car and then put wooden wheels on it!
What can we realistically expect from a high-quality speaker cable?
The ultimate goal of a speaker cable is to get the signal from the amplifier to the speakers without destroying it! Essentially, we want to give the speaker the signal the amplifier intended it to receive. So what you should expect from a high-quality speaker cable is an accurate reproduction of the signal so both your amplifier and speakers are being influenced as little as possible. You purchased your amplifier and your speakers because you liked their sound and we want to help you replicate that. With this in mind, a good, high-quality speaker cable should have low resistance, low capacitance and low inductance, and trust us, this isn’t easy to achieve, but with QED techniques like QED Aircore™ used in the QED Supremus, we do this where others can’t!
You’ve stated that the QED Supremus Cable took 21 years to design, why is that?
This is because our current flagship speaker cable, ‘QED Genesis’, was born from the ‘Genesis Report’ I mention above. When we designed ‘Supremus’, we went back to the original findings we made in 1995 and looked at ways we could improve Genesis, and the result is QED Supremus. Subsequently, we have now developed the ‘Supremus Report’, a white paper with these new findings.
Can you describe its structure?
QED Supremus is a massive, 6.2 mm² cross-sectional-area cable and uses our QED Aircore™ technology. In Supremus, this involves two bundles of 16 silver-plated, oxygen-free copper conductors wrapped around a central PE Aircore™. Each one of the conductors is insulated from the others using enamel insulation and is also cryogenically treated.
What’s the point of insulating each silver-plated copper conductor?
Due to cable ‘capacitance’, the energy, rhythm and timing of the cable can be impacted by having multiple conductors, and the way to remove this issue is by increasing the space between the conductors and insulating them. Until now, in higher-end cables we have been using Teflon as an insulator, but with the Supremus we go one better and use an enamel insulation that has to be stripped off using special machinery. The result in Supremus is a very quick and accurate cable delivering more rhythm and musicality!
Are there any reasons why solid-core conductors might be better than stranded conductors?
We looked into this in some detail in the Genesis report and we concluded that it is more likely to be the insulation and geometry of many solid core cables which are responsible for their generally higher performance than stranded conductors. So again, it is the combination of the conductors and the insulation. With Supremus, we use solid-core conductors as they show lower inductance, which means they are much better at transferring high frequencies.
What is AirCore technology? Can you describe some advantages it has been designed to offer?
Here the conductor bunches are twisted around a hollow, central polyethylene core and separated by further cores to maintain the precise distance between the cores and ensure a consistent twist along the cable. This means that no single conductor is ever on the outside or inside of the entire conductor bunch throughout the length of the cable. This has the benefit not only of keeping both inductance and capacitance low (which is an extremely unique achievement), but also of changing the magnetic field structure of the cable to ensure high frequencies travel through the central part of the conductor rather than become lost to the outside of the conductor. This is known as the skin effect which plagues cables with a larger cross-sectional area, resulting in the loss of high-frequency detail and clarity. With QED Aircore, an unrivalled level of high-frequency detail and cable timing is achieved.
Which speakers would best benefit from QED Supremus cables?
This is a question I always find very difficult to answer because I personally don’t believe in system ‘tuning’ using cables. For example when people use certain cables to dull down a speaker’s brightness, I always respond with ‘why did you buy those speakers then’?
Like I mentioned earlier, the main purpose of a cable is to get the signal from the amplifier to the speakers with as little damage as possible. Therefore, a truly magnificent speaker cable should add nothing or be invisible. So, the simple answer is, all speakers! Now even entry-level speakers would benefit from Supremus, but common sense would dictate that you wouldn’t spend more on a cable than your whole system, so my response would be that any premium bookshelf or floorstanding speakers would benefit greatly by being used with Supremus!
What hi-fi equipment have you chosen for your home?
I have a complete mix really. In my living room I use some NAD masters series equipment with Q Acoustics Concept 20’s and of course all QED cables. But I also love my Q Acoustics Media 4 sound bar which I have two! One for my ‘man cave’ and one in the bedroom. I have a pretty good-sounding house!
Lastly, what is your favorite musical recollection?
I am a big fan of harder and heavier rock and have to say one of my favourite albums of all time is ‘The Colour and The Shape’ by Foo Fighters which at nearly 20 years old, the production still sounds amazing and still has some of my favourite rock songs on, like ‘My Hero’ and ‘Everlong’. I also like electronic music and folk music so a bit of a mix but at my core, I’m a big rock fan!
Read our QED Supremus cable review here.
This post is also available in: French