Are Canare products RoHS Compliant?
Currently, all Canare cable since manufacture date March 2004 is RoHS compliant.
All Canare connectors are available RoHS compliant. If you need such connectors, please specify "RoHS" when ordering.
As of February 2007, Canare will be completely compliant, including assemblies, panels, cable and connectors.What's Balanced and Unbalanced Audio?
Unbalanced connectors are generally RCA (F-10, RCAP) and Phono (F-15) featuring one center contact and one ground contact. Unbalanced cables usually consist of one center conductor with an overall shield (GS-6). To protect against excessive noise incursions, Unbalanced cable assemblies should be limited to 15 foot runs.
Balanced connectors are able to provide greater noise immunity due to the phase cancelling nature of the twisted pairs and are standard equipment in professional audio installations. Balanced connectors have three contacts: two for the signal (+/-) and one for ground shield. The standard connector for balanced cable is an XLR, Bantam Tip/Ring/Sleeve (TRS) or Longframe TRS. (F-16 phono plugs are typically NOT used for pro broadcast balanced audio applications).
Two conductor twisted pair cable such as L-2B2AT (or 4-cond L-4E6S Star Quad) are intended for Balanced circuits, but may also be used for Unbalanced assemblies. One of several wiring tricks, is to solder the blue conductor to the connector's center pin and the white conductor to the shield ground contact. An installer may then choose to "float the cable shield" by not soldering the overall braid (or drain wire) at one or both ends of the cable. This technique may result in better "unbalanced" circuit noise rejection.How do I know if I use 75 ohm Canare BNC Connector?
The connector on the left is a commonly used 50 ohm BNC. Notice that the dielectric (white ring) is visible at the top of the outer contact.
The Canare plug on the right is a true 75 ohm BNC connector. Its dielectric material is recessed... Your visual assurance that there will be proper 75 ohm impedance matching between the source equipment, interconnecting cables, patchbay and load equipment. The end result: no signal reflections (VSWR) for longer cable runs and enhanced system performance. When going back & forth between 2- and 3-wire audio connectors, sometimes I get considerable hum. How do I avoid this?
Two-wire audio connectors are used for unbalanced audio. One wire is the signal (hot) the other is ground and signal return. Three-wire connectors are not as simple. The primary use of a 3-wire connector is for balanced audio where one wire is a separate ground and the other two carry audio. The audio on the two wires is identical, except one signal is out of polarity with the other. Another use of 3-wire connectors is for the insert jack on audio boards. On these, one wire is an input, the other is an output and the third is a Common ground.
Over the last several years, 3-wire stereo plugs (F-16) also have become common in many sizes. These connectors are used for two unbalanced (L&ampR) signals with a common ground. With all of this in mind, the problem you are referring to usually occurs when you mix balanced and unbalanced signals.
The best way to interconnect balanced and unbalanced signals is with transformers that match signal type and impedance. In addition to matching the wiring and impedance, the levels must also be matched. Small pre-amps can be used to boost levels that are too low, and attenuator pads can reduce levels that are too high. If you don't have the proper matching equipment, careful and consistent wiring practices can keep the signals relatively clean.
The first area to look at is ac power. Make sure that all of the audio equipment is powered by the same circuit. If this is not possible, keep the number of circuits small. Second, any ac plugs that are not polarized can be reversed. If noise is detected, reverse the ac plugs one at a time, leaving the plugs in the position that produces the least hum.
At this point, the process can get a little messy. When you wire an unbalanced output to a balanced input, connect the signal wire to the positive, or hot, input. Generally, connect the ground to the negative, or cold, input and to the ground input. Depending on the situation, better results may be obtained if the ground input is left unconnected. When you connect a balanced output to an unbalanced input, connect the signal input wire to the positive, or hot, output, and connect the ground wire to the ground output connection. At this point, check the frequency response at 100Hz, 1kHz arid 10kHz. It should be flat. If the response increases with frequency, place resistors from the positive output terminal to ground and from the negative output terminal to ground. The value of each resistor should be about half the output impedance listed in the equipment specifications.