Maintaining audio and system cables is one of those necessary chores that we all love to hate, and a job that's made considerably easier and quicker if you have a good cable tester. Studiospares claim that their Ultimate Cable Tester is "the most relevant cable tester for the pro audio industry,” and it's certainly one of the most comprehensively equipped testers I've used.
The Ultimate Cable Tester is a manually operated, continuous DC‑voltage design that can accommodate three‑ and five‑pin XLRs, 6.25 A‑type and 3.5mm TRS and TS jacks, phono sockets, DIN sockets in 3-, 5-, 7- or 8‑pin versions, Speakon connectors in 2-, 4-, and 8‑contact variants, and even Cat5 cables. It also has a pair of 4mm sockets for use with a supplied set of test probes for general continuity testing, with a beeper to confirm when a circuit pathway is present. The review unit arrived packaged in an optional all‑metal protection flightcase.
Construction is very simple. but robust, using a pair of U‑shaped folded steel plates screwed together, with screw‑on rubber feet on the base. The numerous connectors are distributed on both sides and across the top, with a rotary switch to select each possible connection path. The circuit‑path results are displayed on two rows of eight LEDs, with two more LEDs used to provide a battery check and to indicate when the selected terminal is linked to the connector's shell.
Internally, it's a bit of a cramped rat's nest of hand‑wiring, between the various connector terminals and a centrally mounted PCB that supports the switch and LEDs. A battery box is accessible from the base end‑panel for easy replacement of the 9V PP3 battery (one of which is supplied). The whole thing is very solid and should prove very reliable, although if the unit is not stored in a suitable case I fear there is a risk that the rotary selector switch could get knocked and damaged. The optional flightcase provides ideal protection and storage for the probes, and I think would be a sensible investment.
Cable testing is very straightforward: the cable under test is plugged into the appropriate connectors, and the rotary switch advanced to test each separate connection path. At each position, the connected terminals are indicated by a green LED on the bottom row for the left-hand socket, and a yellow LED on the upper row for the right-hand socket. The test current is continuous, so intermittent cable faults can be found very easily by waggling the cable and watching to see if the LEDs blink off or if inappropriate LEDs illuminate! It's all very simple, but very intuitive and extremely reliable.
I've yet to find a pro‑audio cable tester with every possible connector on it, but even if it did exist, it would probably be far too large and cumbersome to be of much practical use! The Studiospares Ultimate Cable Tester can't test B‑type, (PO316) round‑tipped quarter‑inch plugs, for example, or the smaller Bantam (or TT) plugs often used in professional console patchbays. It is unable to test the BNC cables that are widely used for video, MADI and word-clock signals. Also, the cable tester only performs a simple DC test, so any semi-conduction or cable capacitance issues that might affect audio or high‑frequency performance (of particular relevance to video, word-clock, data and Ethernet cables, of course) can't be identified.
On the other hand, BNC testing can be accommodated with the use of BNC/phono adaptors, if necessary, and the five‑pin XLR and Speakon test facilities, which aren't offered by some competitors, will be of great value to anyone working in live sound.
The Ultimate Cable Tester is almost identical to Sound Lab's CT4 cable tester, but with Cat5 sockets in place of Mini‑DIN connectors. It's also quite similar to, but cheaper and more comprehensive than, the Palmer Multi Cable tester. Some alternative cable testers, such as Ebtech's Swizz Army 6‑in‑1 and the apparently identical Behringer CT100 offer Bantam connections and additional facilities, such as processor‑based testing algorithms for installed cables, test‑signal generators and phantom‑power detectors, but they have less flexibility overall when it comes to connector types.
So, as I said, I've yet to find a cable tester that covers every possible requirement and eventuality! Nevertheless, Studiospares' Ultimate Cable Tester is definitely one of the best and easiest to use, and the review model has already been added to my inventory of essential tools. Excellent value for money and highly recommended. Hugh Robjohns
Ultimate Cable Tester £30.60; 'Flight' case £14.04. Prices include VAT. Prices exclude shipping.