Cardas Jumpers Clear (Fork)

Cardas Clear Spade Jumpers (spades)

Many dual-binding-post speakers come with small brass plates to link their two pairs of terminals. This is the often-forgotten link, and rarely the best one in the chain. Cardas Clear cable is available only in single-wire configuration, with no bi-wire version: to use it with such a speaker, the brand entrusts this bridging to jumpers made from the same conductor as the cable.

The role of a jumper on dual binding posts

A bi-wire-compatible speaker has two pairs of terminals on the rear: one for the bass section, the other for the treble section, each connected to its half of the crossover. From the factory, two small brass plates link these pairs, so that a single cable powers the entire speaker. These are the plates replaced by Clear jumpers. As long as the connection remains single-wire, a bridge between the two pairs is necessary: without it, half the spectrum remains silent. The original brass provides the electrical connection, rarely anything more. Replacing these plates with a jumper built using a serious conductor extends the cable to the final centimetre, where the signal enters the drivers.

The same conductor as Clear cable

Inside, these jumpers use the conductor from Clear cable, shortened to the length needed to bridge the terminals. Cardas layers its copper strands concentrically, in successive layers, with each strand receiving insulating varnish (a Litz-type construction) and wire gauges based on the proportions of the golden ratio. The copper is Grade 1, 99.9999% oxygen-free. The purpose of this layering is to limit variations in copper behaviour from one frequency to another, from bass to treble, in order to keep the signal consistent across the entire range.

The construction has one practical consequence: for each polarity, the outside of one concentric conductor connects to the inside of the other, so the positive and negative strands remain joined and do not separate. On a jumper, this constraint is no issue, since each speaker receives its complete pair in any case.

Clear cable is not made in a bi-wire version. Rather than splitting the conductors inside the same jacket, Cardas keeps a single cable throughout its length and entrusts the bridging to this jumper made from the same wire. The brand considers this combination more effective than internal bi-wiring.

Forged spades without solder

The spade version ends each extremity with a forged copper lug, pressed directly onto the conductor under very high pressure (around 10,000 psi, nearly 700 bar). The result is a one-piece copper connection, with no solder in the signal path. Cardas forges and assembles these parts in its workshop in Bandon, Oregon.

The spades slide under the nut of screw terminals and accept common terminal diameters, 6 or 9 mm depending on the version. The pair measures 254 mm, enough to connect two pairs of terminals even when they are widely spaced. Sold as a pair, one jumper per speaker, they directly replace the original plates: loosen the terminals, remove the brass, install the jumper between the two pairs, then connect the Clear or Clear Light cable to one of them.

This spade termination requires binding posts that accept them. For a speaker with banana sockets only, look instead at the banana plug version of the same jumper.

Frequently asked questions

Do you need to switch to bi-wiring to use these jumpers?

No, it is the opposite. They are intended for single wiring: one cable arrives at one pair of terminals, and the jumper carries the signal to the second pair. If you choose bi-wiring, with two separate cables from the amplifier, you remove all bridging and these jumpers are no longer needed.

Can they be used with a speaker cable from a brand other than Cardas?

Yes. They replace the original plates regardless of the speaker cable connected behind them. Their benefit remains the same: placing a carefully designed conductor where the manufacturer fitted a brass plate.

How can I check whether my speakers are compatible?

Look at the rear: there must be two pairs of terminals, one for bass and one for treble, linked by removable plates. With only one pair of terminals, the speaker does not accept bi-wiring and these jumpers do not apply.

Does one pair cover a stereo system?

Yes. Each jumper combines the positive and negative connections of one speaker, and the pair includes two, one per speaker. For a standard pair of stereo speakers, one pair of jumpers is sufficient.

How do they differ from other Cardas jumpers?

They sit at the top of the range. Where other Cardas models use 9.5 or 11.5 AWG chassis wire, or a simple stamped copper plate, the Clear version uses the conductor from Clear cable and its solder-free forged lugs. It is also the only one sold as a pair rather than as a set of four.

Can you return to bi-wiring later?

Without difficulty. The jumpers are removed just like the original plates. When you switch to two separate cables, remove them and connect each cable to its pair of terminals.

Technical Specifications

Compatibility

• Designed for use with CLEAR or CLEAR LIGHT speaker cables

Construction

• Transparent conductors for speakers
• Multi-strand concentric conductors
• Superior performance compared to internal bi-wiring

Dimensions and Packaging

• Length: 254 mm
• Sold as a pair