Yes, audio and standards Matter. And that's probably going to be the last word pun I will use in this article, referring to the fact that the new standard for the Smart Home is called Matter. If you are wondering about the literal question in the title and what the concept of Smart Home represents for audio applications, all you have to think about is Wi-Fi. Does Wi-Fi matter for audio in our homes today? Of course it does. Yes, we have Bluetooth as well, but most likely streaming content to devices in the home is available originally through Wi-Fi - basically the convenient wireless network that extends our Internet connections. In fact, Wi-Fi technology has stepped ahead in the majority of homes, replacing old wired Ethernet networks - the few homes who had it, and which never upgraded from the old 10/100 standard, even though all our computers now already have 10Gbit Ethernet.

Residential integrators understand this well. While they have been building structured cabling using Ethernet-based technologies for whole home audio and distributed entertainment systems for years, their clients don't actually care what they use. Residential audio installations have been basically about building stuff behind the walls and hidden on the ceiling, with only screens and loudspeakers visible to the user. And when it comes to connecting those systems as part of a "smart home,” users want to wirelessly connect and control things from their own devices. And that fundamentally means Wi-Fi. Meanwhile, the Smart Home evolved so quickly that the integration business became mostly about configuring control interfaces and protecting access.

In Part 1 of this three-part article about circuit topologies that are used to provide specific functions for an amplifier design, the author discussed cascodes and folded cascodes. In this Part 2, he focuses on current mirrors and line stages. As the author writes, “As designers, we have many devices to choose from. Some devices are ideally suited to certain tasks. Other tasks require performance that is difficult to achieve. While many excellent devices exist today, ideal devices do not exist, except maybe in Spice simulations.” This article was originally published in audioXpress, November 2021.  Read the Full Article Now Available Here

This Test Bench addresses Purifi Audio’s PTT4.0X04-NFA-01 4” midbass, which is very similar to the PTT6.5X reviewed in Voice Coil July 2021, and includes the same constant Sd surround and low magnetic hysteresis motor design, also discussed in a dedicated article by the company’s founders. The distinct cone assembly for this driver consists of a flat profile paper cone made with a proprietary fiber mix, a concave dust cap that covers about 90% of the cone surface, plus the addition of a V-shaped edge reinforcing ring glued around the outside rim of the back side of the cone, which makes the cone edge extremely stiff, and is designed to dampen cone edge resonances. Compliance is provided by a unique NBR surround, which as in the PTT6.5X surround, deserves to be explored, motivating Vance to discuss it with Purifi’s co-founder Lars Risbo. No doubt, one of the most detailed Test Bench characterizations on a product that truly deserves that degree of discussion. This article was originally published in Voice Coil, November 2021. Read the Full Article Now Available Here