Digital audio equipment has been transforming home entertainment by bringing a new level of performance and quality to AV components and overall set-ups. Digital devices are coveted by consumers for their ease-of-use, quality performance, and streamlined designs. Many consumers, however, may have systems with both digital and analogue components, including analogue speakers. These consumers need the help of converters that can translate a digital signal from an optical jack into an analogue signal.
Finding the right converters is, first and foremost, a matter of familiarising oneself with the technical aspects of these devices. Understanding how optical analogue converters work and how they differ from coaxial converters are some of the considerations involved in making an informed purchase decision. One can then utilise the online auction site, eBay, which offers a strong catalogue of options for optical analogue converters. On eBay, consumers can quickly and easily find and purchase optical analogue converters by following simple approaches that take advantage of the website’s functionalities.
Buying Optical Analogue Converters on eBay
The online auction site eBay offers a number of choices when it comes to optical analogue converters. The site also extends a useful search interface, which allows you to quickly begin shopping for an item by running a search. The search bar can be found on any page on the site. You can enter a general term, such as "optical analogue converter", or a more specific term based on your needs to begin reviewing the relevant listings on the website.
Of course, before beginning the purchasing process on eBay, it is important to have an awareness of what is involved in optical-to-analogue conversion and the basics behind these useful adaptors.
Optical Fibre Connection Systems
When consumers see the word "optical" used in the context of audio, they may be confused as to its meaning and application within sound performance. Optical cables and connectors are actually optical fibre connection systems that transmit a digital audio bitstream. Optical fibres are transparent, slender fibres made from silica or, at times, glass, and they conduct an S/PDIF digital signal. Glass is well-known as a quality conductor of light, but plastic cables can do justice to the transmission needs of an S/PDIF signal. Some audiophiles debate over the quality of either option, but in general, they are equivalent options for the average audio consumer.
The optical cables leverage their sensitive structure to act as a waveguide, allowing light to transmit from one end of the fibre to the other. This delivery system makes them capable of transmitting detailed, digital audio with ease. Optical audio cables are often referred to as TOSlink cables, an abbreviation for "Toshiba link", in connection with Toshiba, a pioneer in this field.
How Optical Analogue Converters Work
Optical analogue converters are designed to translate a digital signal from a TOSlink or optical audio cable into an analogue one that can then be read and processed by analogue devices via analogue cables. Optical digital cables link the digital output device to the converter. Optical cables convert the digital S/PDIF signal into red LED light and transmit it via the internal fibre optics of the cable to the converter box. Optical cables are affixed with a light receiver on their far end which receives the transmitted light and decodes the light modulation to extract an output signal. Optical cables emit a red light when powered.
An optical digital cable has a square-shaped, male insert which is designed to push through a small hinged door on an optical port. Once the connection between the cable and the port has been made, a small lens on the cable’s tip begins to read the LED emitted by a device. The lens on the tip of an optical cable is very sensitive and should be protected at all times. Often, optical cables are sold with a protective cover which prevents the lens from getting scratched when not in use.
Mini TOSLink Adaptors
On occasion, a consumer may have a device that has a mini-TOSlink output. These require different jacks and different cables which may not work with an optical analogue converter. In these scenarios, a consumer can use a mini-TOSlink adaptor to make the smaller, 3.5-mm mini jack work with the optical analogue converter.
Coaxial Digital-to-Analogue Converters
Some converters work with coaxial digital inputs instead of TOSlink-style inputs. Some audiophiles prefer the sound of a coaxial digital cable, claiming it provides more true-to-life sound. Many electronic audio devices can have either or both coaxial and digital outputs. Consumers looking for a converter to deal with the transition from digital to analogue should first consider which outputs the digital device has and, if it has both, whether they wish to convert coaxial or optical signal into analogue.
A coaxial cable features a design similar to traditional RCA audio cables, with both a left and a right stereo insert. These orange-coloured digital cables must have an impedance of 75 ohms to operate optimally, and they convert the digital S/PDIF signal to a voltage that can then be transmitted electrically.
Coaxial vs. Optical
If a consumer is deciding between a coaxial converter and an optical converter, there are several factors to consider. The following chart elucidates some of the advantages and disadvantages of both digital conductors and can help a consumer decide on an appropriate product.
Digital Cable Type
|Sturdier design, less prone to damage
May be priced lower
|Uses an electrical connection, can cause ground loop issues
Low levels of hum and buzz may be present
No electrical signal
No hum from ground loop issues
Need to be carefully stored so as not to damage the connector
The above chart provides a general frame of reference when one is deciding how to convert a digital signal. Consumers can use these guidelines when selecting between coaxial and optical cables with a digital-to-analogue converter.
Sound Performance in Coaxial vs. Optical Cables
Audiophiles often discuss the sound performance distinctions between coaxial and optical digital cables. Some believe that a coaxial digital signal has less jitter, which is essentially a timing error in the digital signal which can subtly degrade the quality of the sound. Most humans cannot hear this in performance of an audio system. A consumer who is not too concerned about the sound produced may base the decision on more pragmatic concerns such as ease-of-use or accessibility. For the more discerning consumer, a consideration of the issues that differentiate a coaxial converter and its cables from an optical converter and its cables is required.
Some optical analogue converters also act as audio decoders, allowing a complex signal, such as a Dolby surround sound digital signal, to play on a legacy surround sound system with analogue inputs. These converters take the optical signal and split it into five RCA outputs, which can then port with all of the separate analogue components in a 5.1 surround sound speaker system. These devices are ideal for consumers who enjoy the performance and set-up of their current surround sound system, but want to integrate digital players and devices into the system.
The Purchasing Process on eBay
Once you have reviewed your options and are ready to complete your purchasing process on eBay, you can begin looking at relevant listings in detail. As you scan your search results, look for listings that seem in line with your needs. Click on the title of appropriate listings to visit their detail pages. On a listing’s detail page, you can find important information, such as the payment methods accepted by a seller and the delivery costs involved in shipping an item. You can use these factors to help refine your search for the right item.
Vetting the Sellers on eBay
Another important aspect of the purchasing process on eBay, besides reviewing a listing’s details, is looking through a seller’s page in detail. You can reach a seller’s page by clicking on the name from the listing’s page. On the seller’s page, you can find past auctions that can give you an idea of the vendor’s overall line of products, as well as feedback which has been submitted from other customers. All of this information can help you ascertain whether a vendor has the right optical analogue converter for you.
Optical analogue converters are useful tools for optimising a home audio set-up and connecting digital components with legacy speakers and other analogue units in a system. Optical-to-analogue converters can leverage both coaxial and TOSlink inputs, giving consumers some range in selecting the method by which they can convert the digital signal after they have weighed the performance advantages of each.
Shopping for these helpful devices can be greatly facilitated by the online auction site, eBay. As an aggregator, eBay brings together a number of merchants to provide consumers with a comprehensive range of selections when it comes to optical-to-analogue converters. Consumers can initiate the process by running a search for optical analogue converters via eBay’s search interface. As they find listings they are interested in, it is a matter of taking the time to review the product descriptions and evaluate the sellers before placing an order on the website. eBay’s numerous useful functionalities can make finding the ideal optical analogue converter for one’s home audio system needs an easier and less time-consuming process.