digital-to-analog

High Resolution Technologies makes some of the very best and most affordable digital-to-analog converters on the market. The company's newest model, the MicroStreamer, is a tiny thing, just 2.5 inches by 1.2 inches by 0.4 inch, and since it's USB-powered it doesn't have a power supply or require batteries. It works as an external sound card for computers, tablets, and some smartphones. It's also a high-quality headphone amplifier. It was designed in the U.S., and the little guy's circuitboard's components are mounted in Southern California. The aluminum case is made … Read more

The AudioQuest DragonFly is a USB-powered (it doesn't use batteries or an external power supply) digital-to-analog converter. I usually need some time to get a handle on the sound of a component, but within minutes of plugging in the tiny $249 DAC I knew exactly what made it so special. It sounds clear and clean, so there's less standing between the music and my ears.

The DragonFly is a bona fide audio component, designed by Gordon Rankin, a man known in audiophile circles as a great tube electronics engineer, but Rankin is also a computer audio guy. He's one of the few DAC designers with equal depth of knowledge in analog and digital audio technology.… Read more

Since in-ear headphones sit in or near the ear canal, they don't interact with the pinna, the bends and curves of the outer ear that direct sound to the ear canal. The pinna also serves as an acoustic filter, enhancing the frequency range of human speech, and it also supplies directional cues, so we can localize where sound is coming from. That's how our ears and brains process sound in real life, but in-ear headphones don't interact with the pinna, so they can't sound as realistic as full-size headphones or speakers. In-ears can still sound great, … Read more

I've frequently raved about Woo Audio's all-tube headphone amplifiers in this blog, so I was surprised to see that the company's new WDS-1 digital-to-analog converter (DAC) is a solid-state design. Woo still offers the full line of made-in-New-York-City headphone amplifiers, with prices starting at $495.

There's also a new matching WPT-1 CD transport. Build quality is superb; these components have the sort of detailing you see on high-end gear that sells for two or three times the price of Woo's products. Each unit is 9 inches wide and 13 inches deep so they can be … Read more

If you think a lot of audio has become far too complex, check out the Halide Design digital-to analog converters (DACs). They're plain black boxes, without even a single LED, display, control, button, or connector jack (the DACs come with permanently attached USB and RCA cables).

The elegant simplicity of the Halide Design DACs is a brilliant alternative to most of today's overly complex gear. They have just one function--zeros and ones go in at one end--and analog signals come out the other end. The little Halide black boxes are the best-sounding DACs I've heard on my … Read more

I get this question a lot, "Steve, what's the best-sounding Blu-ray player." Sometimes the questioner is more specific, "I have an Oppo BDP-83, but is the Oppo BDP- 95 better? What are you using at home?"

I have an Oppo BDP-95 ($999), which has a lot in common with the company's BDP-93 ($499) 3D universal Blu-ray, SACD, DVD-Audio player, but the BDP-95 is the potentially better sounding player. I say potentially because that player's upgraded digital-to-analog converter and audio circuitry won't make a nit of difference if you're using the player'… Read more

I wasn't expecting much from the Hifiman Express HM-101; it's just a $39 outboard USB digital-to-analog converter and headphone amplifier. Well, this tiny USB-powered (it doesn't need batteries or an AC power supply) device definitely pumped up the sound of my Audio Technica ATH-M50 headphones! They sounded significantly better with the Express than they did plugged directly into my Mac Mini's headphone jack. Sure, the Mac's sound is perfectly acceptable--until you compare it to something better.

The Express is a lot better.

Before we go any further, the Express isn't just for headphones, it also has a line-out 3.5mm jack you can run to a set of desktop-powered speakers, like myAudioengine 2s. DAC resolution isn't specified, but it's probably 16-bit/48-kHz.

Switching over from the computer's headphone jack to the Express, the first thing I noticed was that the Express could play a lot louder. That's great, but when playing drummer Ginger Baker's "Going Back Home" CD at equal volume levels from the computer and the Express, the Express unleashed more of the drummer's hard-hitting dynamics. The computer squashed his sound, especially Baker's mighty bass drum. Wow, the little thing delivers. If anything, the Express errs on the side of too much bass fullness, which isn't such a bad thing.… Read more

A great headphone amplifier is one that makes headphones sound better than you thought they were. Judged by that standard, the Centrance DACport will be an awesome upgrade for buyers who have already invested in high-quality headphones.

This component, which was made in the U.S., is downright elegant in its simplicity. There's no power adapter or batteries; the Centrance DACport ($400) runs off your laptop or home computer's USB port, and it doesn't care if it's running Mac, PC, Linux, or iOS. The DACport has a 1/4-inch (6.3 mm) headphone jack at one … Read more

Every sound you hear in real life that doesn't come out of a speaker is analog. Analog audio is, simply put, an analogous record of sound, and an LP's groove is a literal imprint of the music's soundwaves. Analog magnetic tape is just as analog, but the waveform is recorded to the orientations of the iron oxide particles bonded to the tape. Tape or LP, analog recordings store audio signals as a continuous wave in or on the media and therefore have theoretically infinite resolution.

Digital audio recording converts the original sound into a sequence of numbers; sampled to convert the analog signal to a digital representation. Sampling is the division of the signal into discrete intervals (CD's sample rate is 44.1 thousands of samples per second). CDs have a 16-bit resolution and DVD-Audio discs can be encoded with a maximum of 24-bit resolution. DVD-A's have greater bit depth results in finer gradations of sound compared with CDs and MP3s, and is subjectively on par with analog recordings. Analog-to-digital processing is performed by a converter in the recording studio; and must be converted from digital-to-analog to be listened to.

If I lost you with all that talk about sampling and conversions, let's just say the prime difference between analog and digital is that analog recordings are continuous in time, and digital is sampled at distinct intervals. What happens between samples? Not much. Analog is always "on," digital is either on or off. Analog recording's theoretically infinite resolution refers to its continuity, compared with digital's on/off sampled nature.

If digital audio sounds a lot more complicated than analog, that's because it is. But digital recording offers very significant advantages over analog recording; it has inherently lower noise, perfect duplication capabilities, and superior speed accuracy (lower wow and flutter).

Most of the digital audio advances since the early days in the 1970s come from today's superior A/D and D/A converters. Digital audio has never sounded better than it does now.

The same can be said about analog: the best LPs, played back on a good turntable sound more like real, live music played by human beings than digital recordings ever do. That's my subjective opinion. On a more objective basis I'd say digital eliminates, or lowers analog-type distortions (noise, speed variations, and so on), but it suffers from far from perfect analog-to-digital and digital-to-analog conversion processes. To many, but not all, audiophiles and recording engineers, the best digital still sounds sterile, cold, and lacks natural warmth.… Read more