IPod the iPod Nano and Shuffle from its stores, marking the end of Apple producing standalone music players. Currently, the iPod Touch is the only iPod produced by Apple. The third-generation iPod had a weak bass response, as shown in audio tests. The combination of the undersized DC-blocking capacitors and the typical low impedance of most consumer headphones form a high-pass filter, which attenuates the low-frequency bass output. Similar capacitors were used in the fourth-generation iPods. The problem is reduced when using high-impedance headphones and is completely masked when driving high-impedance (line level) loads, such as an external headphone amplifier. The
IPhone instruction leaflet, but as with many newer iPod models the battery in the first generation iPhone has been soldered in. Therefore, a soldering iron is required to install the new battery. The iPhone 3G uses a different battery fitted with a connector that is easier to replace. The iPhone X features a different battery, with two battery cells, and the adhesive pull tabs are adhered to the sides instead of folded over the top, therefore making repairs a little more difficult than before. A patent filed by the corporation, published in late July 2013, revealed the development of a new