Gio Militano writes:
Until recenty my desktop computer has always shared a room with a Hi-Fi setup so there has never been a need for using decent speakers with the computer. When the desktop computer was moved into it’s own room (with no HiFi) I quickly realized that good speakers were now required for decent quality music playback. I had been using some low cost Radio Shack speakers with an inexpensive Tripath based amplifier and I was really itching for an upgrade.
Fostex FE103En Bass Reflex Bookshelf Speakers - [Link]
Researchers at Harvard University have demonstrated a new type of loudspeaker transducer which works on a different principle to the conventional moving coil design. It is made up of a thin sheet of transparent rubber sandwiched between two layers of salt water gel. A modulated high voltage signal passed across the two outer gel layers exerts pressure on the rubber membrane, causing it to vibrate and produce sound. The prototype speaker has a frequency response from 20 to 20 kHz.
The effect is produced by the electrical charges carried by ions and not the movement of electrons so strictly speaking this is not an electronic device. The new transducer could be used as an adaptive lens in an optical system or as a window-mounted noise cancellation device. The electrolyte gel is biocompatible so there could also be applications as artificial skin or muscle. [via]
Ionic Gel Speaker - [Link]
Kyocera has developed an ultra-thin, lightweight audio device, dubbed the Smart Sonic Sound, based on the company’s fine ceramic technology.
The 1mm-thin speaker uses a piezoelectric actuator combined with a special film to create a piezo film speaker, enabling the manufacture of very thin TVs, PCs and tablets with improved audio quality. The device’s low directivity characteristics broaden the sound projection range, providing 180-degree sound quality and bringing delicate and minute sounds to life, says the manufacturer.
This piezo actuator audio technology is already in use, LG Electronics integrated it into its 55” curved-screen OLED TV. Smart Sonic Sound comes in three different sizes, 70×110×1.5mm, 35×65×1.0mm and 19.6×27.5×0.7mm, with respective frequency ranges of 200Hz to 20kHz, 500Hz to 20kHz and 800Hz to 20kHz. They weigh 23g, 7g and 1g respectively.
1mm-thin, lightweight piezo film speaker targets thin TVs, tablets - [Link]
Reliable loudspeakers needn´t be expensive. K50/8 from company Visaton is a good example of a universal louspeaker suitable even to less favor conditions for a very affordable price.
K50/8 belongs to 5 cm (2“) industrial loudspeakers with an increased resistance. IP65 (from the side of membrane after building into an appropriate housing) says it all. Plastic membrane from mylar is UV-resistant and a metal basket ensure a long-term stable properties in a wide range of temperatures. K50 easily handles what it is intended for – reproduction of voice and various sound in a wide frequency range (naturally except low and highest frequencies). K50 also meets another requirement important for the most of applications – small profile – 17mm only. Similarly like the most of small loudspeakers, also K50 is virtually omnidirectional even at higher frequencies (-5db/90°/8000 Hz)..
Thanks to its small dimensions, low profile, resistance and last but not least also an affordable price is the K50 a suitable component for a sound output of various devices like audio door-keeper, lifts, machines and control panels. K50 and many other Visaton components are our standard stock items. In case of interest in non-stock types, please contact us at email@example.com
Add a sound to your devices – for an outstanding price - [Link]
Irdroid v2.0 is advanced version of the Irdroid remote control hardware. The unit is standalone, powered by 12V DC adapter and it has a bluetooth communication module. The unit features a infra-red remote control for android and a Bluetooth Music receiver in one. The module can be used simultaneously to control home TV/AV equipment and to turn any speaker into a wireless bluetooth speakers.
Irdroid v2.0 – universal remote for Android - [Link]
A new chip from NXP can boost the output power of micro speakers by more than five times, vastly improving the sound quality of mobile devices. By driving over 2.6 watts RMS into micro speakers that have previously been limited to 0.5 W, the TFA9887 IC will give mobile phones, portable music players and tablets much louder sound, deeper bass, and higher sound quality without risking speaker damage.
Adaptive excursion control measures the actual excursion of the speaker membrane to ensure that it never exceeds its rated limit. Real-time temperature protection measures the voice-coil temperature directly to prevent thermal damage. An advanced clip avoidance algorithm monitors audio performance and prevents clipping, even when the power supply begins to sag. Bandwidth extension increases the low frequency response well below speaker resonance. And an intelligent DC-to-DC boost converter maximizes audio headroom from any supply level despite battery undervoltage. The chip automatically adapts to any changes in the speaker – including ageing, damage to the enclosure, and blocked speaker ports – helping to optimize performance and maintain the desired sound quality. [via]
Novel Speaker Driver Delivers Hyperaudio from Mobile Devices - [Link]
Knowles Sound Solutions has launched a specially developed material called N’Bass Virtual Back Volume, designed to improve the acoustic performance of speakers in devices with small form factors. N’Bass stands for ‘enhanced bass’ and it increases the apparent back volume seen by the loudspeaker driver by up to 100%. It can provide better acoustic performance – specifically more bass – or enable smaller loudspeaker box designs while maintaining the same performance. It also facilitates the use of bigger drivers to provide better sound performance in the same total volume. [via]
Miracle Material Doubles Speaker Volume For Better Bass Response - [Link]
I made this portable speaker in the summer. It mixes the stereo input into a mono signal, which is then amplified. It’s powered by a six pack of AA batteries. The batteries are held in an external battery pack, so they are easy to change on the fly, without the need of a screwdriver.
Portable speaker for MP3 player - [Link]
Due to its simplicity (requires minimum external components) and high availability, LM386 is very popular among hobbyists for use in low-voltage audio amplification applications. Most of the time a potentiometer is used at the input side of LM386 to provide a volume control in the output soundbar speaker. The potentiometer does not control the gain of the amplifier itself, but it creates a voltage divider network at the input, which in fact controls the fraction of the audio signal that is fed to the amplifier. This project is about a stereo audio amplifier using two LM386 ICs with digital volume control for both left and right speakers. So, how would you control the volume digitally? You are right, by replacing the traditional electro-mechanical form of potentiometers with digital potentiometer chips. This project uses MAXIM’s DS1868 dual digital potentiometer chip and a PIC microcontroller to control the volume of a stereo output from two LM386 ICs.
LM386 based stereo audio amplifier with digital volume control - [Link]