Multi-pins connect the snake trunk cable to the snake head and splay, with the two most popular connectors being Mass and Veam.
Originally developed by Cannon for the oil exploration industry, the Mass connector is a screw-on connector that comes in 122 pin (40 channels) and 176 pin (56 channels) formats in a hermaphroditic configuration with half of the pins male and female.
The advantage with the hermaphroditic design is that you can deploy the cable from either end. The downside is that the pins are relatively small and one has to be careful when mating as misalignment will cause damage.
The C5015 Mil Spec developed by the U.S. military employs a quartertwist bayonet connection with a rugged circular metal body in a variety of pin configurations that often range from 37 pins (12 channels) to 201 (66 channels). The most common used on concert snakes is a 150-pin (50 channels) design originated by Veam and now offered by a number of companies.
The benefit of the circular bayonet is that the pins are larger and easy to replace due to the rubberized pin insert. The 201-pin option allows for more channels, but cable size and pin fragility should be considered.
Custom shops build snakes using all of these. Considerations when selecting a multi-pin connector includes compatibility with older snakes, crossrental opportunities with other sound companies in your area and personal preference based on experience with a given product.
Snake “heads” come in a multitude of sizes, varieties and capabilities.
With more than 150 wires crammed into such as small space, multi-pins are time consuming to wire and repair. Outfitting the snake with a proper Kellems Grip strain relief will protect the sensitive wiring inside the connector and reduce field service.
Snakes & Splitters
Most concert snakes are in fact splitters. What this means is that the signal from the stage microphones and direct boxes are split to feed the house mixer and monitor mixer.
Often these are set up with an auxiliary output that can be used to feed a broadcast truck or recording system. And with more bands using backing tracks and computers, we find that 48 channels is now the minimum used for most productions.
As the XLR connector is the only ‘standard’ in balanced professional audio, it’s a really good idea to outfit the snake with an XLR panel or a spare trunk with XLR outputs. Broadcasters are well familiar with the problems of hum and buzz that plague most stages and therefore will generally have a transformer isolated input panel at the truck.
This leads to a discussion on transformers. Audio transformers allow audio to pass while blocking DC. They also allow the ground to be disconnected between consoles, thus eliminating ground loops. Good quality transformers are expensive but they sound much better (less distortion, more linear, less phasing) and can save countless hours of trouble shooting as they eliminate noise.
Normally, the house console is connected directly to the microphone, thus providing a return path for 48-volt phantom power for condenser mics and direct boxes while the monitors will be isolated. To save money, some sound companies will opt for a “Y” or hard-wire split whereby the microphones wires are simply wired in parallel to feed the monitors and the ground is disconnected. This can work, but is prone to noise and ground loops.