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Speaker cable seems simple. But it sits between two active devices: an amplifier which responds to how it is loaded, and a speaker which presents a highly reactive load whose characteristics vary with frequency and state. These conditions call for some obvious, and some less obvious, design objectives. We'll describe the Iconoclast design, and its objectives, briefly below; but for a full treatment of the subject, please read the articles Time and Speaker Cable Design Brief, and, for our Series-2 product, Series 2 Speaker Cable Design Memo. The designs are proprietary, but the electrical theory behind all of this is meant to be open, explicit and clear: no hiding the ball.
Conventional speaker cable design is simple, and it's not hard to produce a relatively flat frequency response, as measured purely by amplitude. But Galen's principal objective was not just to do that, but to do something trickier: adjust the cable design to keep the timing of low and high frequencies together, despite the fact that the velocity of propagation of signals varies considerably through the audio band. As the papers referenced above set out, this was achieved by using a large number of small conductors, bonded into pairs, in thin-walled Teflon dielectric, and then weaving those pairs tightly together into two polarity bundles.
Beneath the plain squared profile of the original Series-1 Iconoclast speaker cable lies a surprisingly complex design. Each polarity leg of an Iconoclast speaker cable is composed of twenty-four 24 AWG conductors. These conductors are twinned into Teflon®-insulated "bonded pairs," akin to those you may be accustomed to seeing in Belden's data cable products. These twelve bonded pairs are then braided in a basket-weave configuration and flattened to a rectangular profile. The two polarity legs are then laid back to back, and a nylon braid (red/black for ETP, blue/black for OFE or SPTPC) and FEP outer sheath complete the cable. It's a bear to terminate, with 192 wire strips per pair of speaker cables, but the electrical characteristics are hard to achieve any other way.
Electricals (typical):
While the full rationale for this design is set out in Galen's papers, a few points bear mentioning here. Keeping resistance low requires keeping wire cross-sectional area large, but simply using large stranded conductors results in relatively high inductance and inconsistent current density relative to frequency. This can be solved, as here, by using a large number of separately insulated conductors, but the effect tends to be a considerable increase in capacitance, which can present problems with amplifier final loading, and an inconsistent presentation of the various wires within a polarity to the opposite polarity, with each wire having its own separate set of reactive variables. The braided configuration here manages to solve these problems -- inductance is significantly reduced with only a modest increase in capacitance, and the individual conductors each stand in the same orientation to the opposite polarity as one another.
The question remained, though: might one flatten that VP curve further still, by going to still smaller conductors? The math supported it, but serious production questions remained as to whether the cable could be practically made, whether the electricals projected for it would be borne out in practice, and whether it was practical to terminate. After an experimental run at the Belden Engineering Center in Richmond, Indiana, the answers were all positive, and in 2022 we introduced the Series-2 speaker cable, with twice as many conductors, each of 28 AWG. To the left is a picture of a stripped polarity of both versions, showing the difference.
The Iconoclast speaker cable isn't particularly suited to bare-wire termination, as the strands are unruly to manage. Accordingly, we offer a couple of types of termination which will work with the great majority of speaker binding posts.
For these terminations, we use our own special method: ultrasonic welding. Where gas or arc welding result in high heat, which can damage cable and connectors, ultrasonic welding takes place near room temperature, fusing metal to metal by intense vibration with less resultant heat than one would get from soldering. The welded joint is strong, has extremely low contact resistance, excludes oxygen very effectively, and does not introduce any other material to the joint -- the copper wire is fused right to the connector.
Our welded spade lugs are made of rhodium-plated copper, and come in three sizes: a 6.3mm opening, a 7.0mm opening, and a 9.2mm opening. The smallest spade fits the majority of binding posts, but some are a bit over-sized and need the medium; still others that are beefier require the largest. The spade is angled at about 25 degrees from the axis of the cable, but because these are made of copper they will tolerate a bend -- so if you need to change the angle, a couple of minutes with a couple of pairs of pliers will do the trick.
For tighter post configurations, or for those who simply prefer them, we also offer banana plugs, made from brass and plated with gold. These are the same "locking type" banana plugs you may have seen on Blue Jeans Cable products. The plug's locking feature -- enabled by turning the outer collar after the plug has been inserted in the binding post -- ensures tight, mechanically stable engagement with the post.
What style of termination to go with? Well, our preference, barring a lack of room to accommodate them, is for spade lugs; when correctly fitted, these will give you the greatest contact surface and most durable connection. We've found that people find binding posts hard to measure -- you can check yours with calipers if you have a set, but if you aren't sure what size of posts you have, give us a call and we will send you our free spade-sizing card. It has cutouts for our three spade sizes and a QR code for the video showing how best to use it to measure your posts. Note that most posts have flattened areas on the stem which, ideally, your spades should line up with for the most secure fit possible.
If you have particular custom requirements -- such as a need to attach to terminal strips, Speakons, or what-have-you, let us know. We try to accommodate custom termination requests whenever possible, usually at no increase in price.
All cables are accompanied by a test report showing final measured values for capacitance, inductance and resistance.
The Series 2 speaker cable, in addition to being a full-spectrum speaker cable, can also be used in conjunction with the Series 1 cable, in a biwired configuration, with the Series 1 cable handling the lows and the Series 2 handling the highs. While Series-2 by itself has a flatter VP curve than Series-1, this combination flattens the curve a bit more overall, for a biwired cable with both the low and high legs truly separately optimized for the job.
For most users the best way to biwire this setup will be to simply order separate runs for the lows and the highs. This will work well on most binding posts, with either "sandwiched"" spade lugs on each binding post or one run going in by spade and the other going in through the banana opening on the post, and it also has the advantage of making your cables easier to repurpose in case of future tweaks and equipment changes. However, we do and can build these in biwired configurations, where there is only a single set of spades or bananas at the amplifier end; contact us if you want to pursue this.
There are three options available for the conductor composition in Series 1, and two in Series 2. Note that the difference between these is NOT a difference in design -- nothing about the electromagnetic properties of the design is affected by the choice of conductor. Regardless of the material choice, the internal structure is the same, the manufacturing process is the same, and the termination methods and hardware are the same, with the full benefits of Galen Gareis' design work in each.
The conductor choices for speaker cable are TPC, OFE and SPTPC. TPC is Electrolytic Tough-Pitch Copper, widely used in communications cable of all sorts. OFE is Oxygen-Free Electrolytic Copper (99.99% pure), and we offer this in the Series 1 speaker cable only. SPTPC is Silver-Plated Electrolytic Tough Pitch Copper. The outer jacket color is red/black for TPC, blue/black for OFE or SPTPC.
We accept returns for any reason whatsoever within 30 days of purchase.
To see prices and to order, use the tables below.