# HiFiTested > Hi-fi buying guides: headphones and IEMs, DACs and headphone amps, bookshelf and floor speakers, turntables, streamers, amplifiers and cables, explained in plain English. HiFiTested publishes hi-fi gear reviews, buying guides and reader discount codes. Every review states who the product suits, the current price from the brand's own store, and any active reader code. ## Key pages - [Buying guides](https://hifitested.com/guides): how to choose - [Glossary](https://hifitested.com/glossary): hi-fi gear terms defined - [Work with us](https://hifitested.com/work-with-us): how brands partner with HiFiTested for reviews and reader codes - [How we test](https://hifitested.com/testing-methodology) ## Topics - [Headphones](https://hifitested.com/category/headphones): Over-ear and on-ear headphones: open-back for home listening, closed-back for isolation, planar and dynamic drivers, wireless noise-cancelling models. - [DACs & amps](https://hifitested.com/category/dacs-amps): Dongle DACs, portable DAC/amps, desktop DACs and headphone amplifiers, balanced outputs and power matching. - [Setup & listening](https://hifitested.com/category/setup): Room placement and treatment, cables and connectors, lossless and hi-res formats, and safe listening levels. ## Buying guides - [Bookshelf Speaker Placement: Get Better Sound for Free](https://hifitested.com/guides/bookshelf-speaker-placement): Set your speakers and your listening position in an equal-sided triangle, raise the tweeters to ear height, pull the speakers at least a short distance from the wall behind them, and angle them slightly toward you. These free adjustments often improve imaging and bass control more than a costly upgrade. - [Do You Need a DAC? When an External DAC Actually Helps](https://hifitested.com/guides/do-you-need-a-dac): Every digital device already has a DAC, the chip that turns digital audio into an analog signal. You need an external one when your phone has no headphone jack, when your built-in output hisses or lacks power, or when you want balanced outputs and better amplification. A small dongle DAC solves most of these problems for little money. - [Headphone Impedance and Sensitivity Explained](https://hifitested.com/guides/headphone-impedance-and-sensitivity-explained): Impedance (in ohms) and sensitivity (in dB) together decide how much power a pair of headphones needs to play loudly and cleanly. Low-impedance, high-sensitivity headphones run well from a phone or laptop. High-impedance or low-sensitivity headphones, common among open-back and planar models, often need a dedicated headphone amplifier. - [Open-Back vs Closed-Back Headphones: Which Should You Buy?](https://hifitested.com/guides/open-back-vs-closed-back-headphones): Choose open-back headphones for quiet rooms where nobody minds hearing a little of your music: they sound more spacious and stay cooler on your ears. Choose closed-back headphones for offices, commutes, recording and shared spaces: they isolate you from noise and keep your music private, at the cost of a slightly more closed-in sound. Contact: info@hifitested.com