It is important to decide whether you are going to use balanced or unbalanced inputs. As a rule of thumb, unbalanced inputs should be used to connect sources that are located close to your Zone unit - in the same equipment rack for example.
Longer cable runs are more susceptible to noise - using balanced inputs will minimise unwanted noise.
Unbalanced Circuits
In an unbalanced circuit, the signal is carried on a single conductor and the shield, or ground. The shield is designed to help reduce interference, but if unwanted noise is introduced on a single conductor, it is added to the signal and arrives at the input, where it is seen as one and the same thing as the audio and will be heard as hum, buzz or other noise.
Unbalanced circuits are generally fine for short cable runs, and are found on most domestic and commercial AV equipment.
Balanced Circuits
In a balanced circuit, the signal is sent on two conductors. The source sends the signal and an inverted signal. Any noise is induced equally on each conductor, with the same polarity. On arrival at the input the two signals are summed and the inverted signal has its polarity revered - this cancels noise. The shield acts as just that, to help minimise any induced noise.
Connecting Balanced Audio Equipment
If you are connecting a piece of audio equipment that has balanced line outputs on a 3 pin XLR, a mixer or a DJ console for example, you will need a female XLR for the equipment end wired to the appropriate Euroblock connector for the input on Zone.
The little green Euroblock connectors are supplied with your Optimal Audio Zone and SmartAmp products. It's really important to follow the pin connections correctly. The cable you use will have clearly defined cores, and they must connect the three pins on each connector together as shown in the table.
When you solder up the XLR look very carefully at the numbers on the pins to ensure you make the correct connection.
For microphones and remote (balanced)line inputs on Zone and SmartAmp products:
1x Euroblock 3.5mm pitch 3 pin
1x XLR female in-line connector
2 core and screen standard signal cable
| Connect these pins | |||
| Euroblock | ⏚ | - | + |
| XLR | 1 | 2 | 3 |
Connecting Unbalanced Audio Equipment
For unbalanced line inputs you'll need RCA connectors. The inputs on Zone are stereo, so you can use paired cables off the shelf.
It's always worth avoiding cheap RCA connectors, so make sure you go for something robust, with solid centre pins and preferably a steel outer casing.
If you are going to make up your own cables, again it's important to observe the correct wiring convention. Use high quality, flexible coaxial audio cable. The centre core connects to the centre pin, and the outer screen to the outer sleeve.
For local line inputs on Zone products:
RCA phono connectors
Use these for equipment situated close to your Zone - streamers, CD players, phones, laptops etc.
Connecting Laptops, Tablets and Phones to Zone Unbalanced Inputs
Most laptops have built in HDMI ports. We recommend using these for an audio connection to a Zone.
Tablets and mobile phones have a standard 3.5mm jack headphone output, or an adapter that will convert to 3.5mm jack. MP3 players, many phones and other domestic audio sources use them too. Again, these cables are readily available from cable suppliers and home electronics stores.
If making your own, make sure that you get the left and right signal wires on the correct pins in both the jack plug and the RCA cables. Be careful not to short out any of the terminals in either connector.
For local line inputs on Zone products:
RCA connectors to 3 pole (TRS) jack - 3.5mm or 6.35mm size
Forconnection of laptops and other equipment with stereo jack outputs using standard mic cable.
Note the wiring - very important!
| Connect these pins | |||
| RCA Left | Centre pin | Sleeve | |
| RCA Right | Centre pin | Sleeve | |
| Jack | Tip | Ring | Sleeve |
Connecting AV Equipment to Zone HDMI Inputs
Inputs 5 and 6 on all Zone products need Type A standard HDMI connectors. These are readily available either online or in consumer electronics stores.
Be sure to identify the correct type of HDMI connector on the equipment you are plugging in - there are three types of HDMI connectors - Standard, Mini and Micro - they are all compatible with each other.