Have you ever heard noise in the background while your headphones are plugged in and no sound is playing? This can be caused by several factors, and this article will show you some solutions to solve this inconvenience.
Noise can be a sign that something is wrong with your equipment, and most of the time, it is caused by electrical and magnetic issues in the device’s power supply. However, this can be caused by interference in cables or computer boards as well.
The importance of electrical energy in audio quality
Few know, but the electrical energy that reaches the headphone system (composed of a source, amplifier and transducer) influences the final audio quality. This occurs because audio equipment is sensitive to fluctuations in electrical energy, and this ends up passing on to the sound generated by headphones.
Some actions can improve the power quality of the desktop, DAC or amplifier, such as the use of SPDs (electrical surge protection devices), power filters, power conditioners, sinusoidal double conversion online nobreaks, grounding the sockets and cables with shielding.
What is grounding used for?
Equipment that consumes a lot of energy, when turned on and off, causes voltage fluctuations, and these cause noise in audio equipment. To mitigate this, it is necessary to have the grounding of sockets to drain part of the voltage variations (mainly overvoltages).
The grounding of the house is also important for absorb the static energy that accumulates in the structures of the equipment. In addition, the ground wire is important for electronic devices to have a reference voltagein this case a zero voltage (=0V), so that it works correctly.
As radio frequency waves generated by cell phones, transmission towers, communication radios, FM radios, etc., angry interference in audio equipment when absorbed by the structure of devices or cables. To solve this problem, grounding of sockets is used. together with the use of ground wire in the cables, causing the elimination of unwanted noise in sound generation.
The use of Electrical Surge Protection Devices (DPS)
Voltage fluctuations can arrive via the public power grid (outside the house) or the house’s internal power grid. To protect yourself from fluctuations in the public network, you must install on DPSs power boards such as the Clamper VCL Slim. To prevent outbreaks generated inside homes or apartments, the solution is to use of DPSs in line filter format such as, for example, the Multiprotection Clamper 8 or the iClamper Energia 5.
Briefly, electrical surge protection devices serve to prevent damage to any component or burning of appliances.
Powerline noise filtering
Noise filtering from the power grid is present in power conditioners, sine type double conversion UPS e products with DPS and filter functionlike the Clamper products mentioned above.
The filtering of noise coming from the electrical network of the public network or from inside the residence itself is provided by electronic filters who apply a signal flicker attenuation cutting the peaks harmful to the devices. These filters have certain limitations to actbut most of the time they are enough to satisfactorily attenuate the noise in the electrical network.
An important point to note about the precaution of noise generatedis when several pieces of equipment are connected in a single structure with multiple outlets. When you have several devices connected at the same time, it is possible that the connected devices generate interference with each other. This occurs because the filter ends up blocking the flow of noise generated by the devices, which may cause interference.
The interference generated between the system’s electronics, which was mentioned above, may end up causing a degradation of the sound quality generated in the headphones.
power conditioners
The power conditioners These devices have the function of protecting the system’s equipment against lightning and large fluctuations in the electrical network, as well as filtering electrical noise. Basically there are two types of conditioners, the one with galvanic isolation and the energy regenerator.
Conditioner with galvanic isolation It has a voltage transformer that provides isolation between the input and output power. In this way, the phase and neutral connection are isolated from the input electrical network, thus behaving as a completely isolated socket and independent from the electrical network of the house.
This type of conditioner has the ability to eliminate the main noise generated by ground loops, which end up taking an improper path through the grounding of the equipment. This generated loop ends up reaching the input circuit, producing buzzing (the “hummm” sound, generated by the 60Hz frequency of the electrical network).
A conditioner with galvanic isolation, when relying on a traditional transformer, is already able to provide a better performance in reducing noise from the electrical network. However, when an electrostatic shield is added to the transformer or when electrical energy is converted in a balanced way, there is a much better performance in blocking electrical noise.
The electric energy regenerator conditioner, has a more complex and expensive design. This type of device operates similarly to a high-power amplifier, where a 60Hz sinusoidal generator is located at the source, providing “pure” electrical energy to the amplifier.
In order to obtain “pure” energy, the regenerator conditioner transforms the alternating current supplied by the public electrical network into a direct current and then transmits it to the aforementioned amplifier. By carrying out this procedure, it is possible to obtain a new pure electrical network voltage, with 60Hz.
Sinusoidal double conversion UPS
With the use of a sine type double conversion UPSone gets result that comes close to what is provided by an electric energy regenerator conditioner (at a significantly lower cost).
The double conversion nobreaks work by feeding a battery that is recharged all the time, while connected to the socket. In this way, whatever is connected to them will be isolated from the electrical network. This occurs because the UPS input circuits and battery are capable of absorbing all the variation generated by the power grid, including the noise that arrives at the UPS input.
There is only one type of UPS that is indicated for the use of audio and video applications, which is the double conversion subtype, pure sinusoidal, that is, discard almost sinusoidal or similar options.
Shielded cables and quality connectors
This may seem silly or even obvious to some, but using well-made cables and quality jacks will help with the final audio quality. In the case of cables, it is important that they have three characteristics:
- Armor: to avoid radio frequency interference. It also helps to reduce the 60 Hz frequency and harmonics generated by induction.
- Ground wire: to avoid interference caused by the accumulated static energy of the devices, to have a voltage reference and to eliminate noise arising from radio frequency waves.
- Quality connectors: to provide better contact for both the appliance and the outlet.
However, there is no point in having a good power cable and not using one. quality socket. The ideal is to find a socket that has a very tight, firm fit, which provides the best possible contact between the cable connector and the fit in its structure. For this, generally hospital standard sockets are usually used or audiophile recordings such as, for example, that of Oyaide.
Noise generated inside the desktop
Noise can affect the sound cards soldered on the motherboard (onboard). This is due to the way the power circuits are made. Because of this, many prefer to use external devices for audio processing, using the USB, coaxial (S/PDIF) or Toslink output. For audio processing independent of computer hardware, a dedicated DAC or a DAC/amp is used, which sometimes deliver better performance for a lower price compared to an off-board sound card.