amp

Monster founder's son flies solo with Sol Republic headphones launch

We test a lot of headphones here at CNET, and the good ones tend to set you back more than $100. But a new headphone company, Sol Republic, is hoping to change that with a line of headphones that deliver very good sound and durability for a more affordable price.

In case you're wondering what "sol" stands for, it has nothing to so with the sun but is an acronym for "soundtrack of life." The company's founders have a good pedigree in the headphone business, and co-founder and CEO Kevin Lee is the son of Monster Cable founder Noel Lee and is credited for driving the popular Beats by Dr. Dre line of headphones at Monster. … Read more

Top 10 great-sounding amplifiers from $40 to $450

This Top-10 list of great-sounding solid-state and vacuum-tube amplifiers includes headphone amps and vintage models. Most are light on features, so if you need autosetup, GUI menus, AirPlay, iPod/iPhone/iPad compatibility, home networking, HD Radio, Bluetooth, HDMI switching, digital-to-analog converters, Dolby and DTS processors, that's not the main plan. The focus is on amps that provide the maximum sound quality for a minimal investment, but I included one receiver with some of those goodies.

I'll do a top-10 affordable speaker list soon.

Dayton Audio DTA-1 Amplifier ($40)

It weighs almost nothing, looks cheap and flimsy, but Dayton'… Read more

NAD 3020: Vintage hi-fi that still sounds great

I recently bought a NAD 3020 integrated amplifier on eBay for $66. The little amp was a smash hit in 1980 and instantly put NAD on the map. While the amp made its reputation as a giant killer, it's not very big--just 16 by 3.75 by 10 inches. And the look is bare-bones basic. The sound is something else again; as soon as I fired it up I remembered why budget-minded audiophiles bought more than a half million 3020s in about three years, making it the best-selling integrated amp of all time.

It was rated at just 20 … Read more

A sweet-sounding USB digital amplifier for headphones and speakers

The nice folks at Parts Express sent over an amazing-sounding little amplifier, the $129 Topping TP30. It's a tiny desktop Class T amp design, with one analog RCA stereo input and one USB connection (the TP30 has a built-in digital-to-analog converter). The amp delivers 15 watts per channel to 4 ohm-rated speakers (10 watts into 8 ohms), and has a 3.5 mm headphone jack on the front panel.

With its extruded aluminum chassis, 8mm thick, CNC-machined front panel, and solid-metal volume control knob the TP30 wouldn't look out of place in a high-end system. It even feels expensive, but I have just one nitpick: the illuminated blue LED ring surrounding the volume control knob is too bright. I wish there was a way to dim it or turn it off. The amp measures a tidy 4.13 inches by 1.77 inches by 8.07 inches.

The USB interface utilizes standard Windows audio class 1 drivers (it worked fine with my Mac mini). Internal parts quality is superb; the TP30 boasts Elna capacitors, Dale resistors, and an ALPS volume control. The Burr-Brown USB digital-to analog converter chip accepts up to 48 kHz sampling rates with 16-bit resolution.

I compared the sound of the TP30 with my Audioengine N22 amp ($199), and they're both pretty good. The N22 has a fuller, warmer tonal balance, but the TP30 has a more immediate, detailed sound with more tightly controlled bass. I used my Audioengine P4 speakers for all of my speaker-based listening tests. It's interesting, the TP30 is a digital amp and takes digital signals "straight-in" via its USB port; the N22 is analog-only and is a more traditional Class A/B amplifier design. It sounded softer, and a wee bit less defined than the TP30.… Read more

Mission impossible: A bona fide audiophile headphone amp for $219

I don't remember who told me about Bottlehead, but I'd like to thank whoever it was that made the introduction. I review and play around with a lot of audio gear, and as much as I love great budget stuff, the best-sounding products are always a lot more expensive. Not this time; the Bottlehead Crack amplifier I'm reporting on today goes for just $219, and it sounds like it's five times that price. Bottlehead has been selling electronic kits for 17 years.

First things first; $219 buys the Crack as a build-it-yourself kit, but Bottlehead's founder Dan Schmalle assures me the kit is super easy to build by anyone who knows which end of a soldering iron gets hot. It should take an evening or two to complete. The Crack is an output transformerless amp, specifically designed for high-impedance (100 ohms or higher) headphones like many Sennheiser, AKG, and Beyerdynamic models (Bottlehead offers other amps tuned for low-impedance Grado, Audio Technica, etc., models).

Most Bottlehead customers buy the kits, but the company sells factory-assembled Crack headphone amps for $369, and considering the Crack's build and sound quality, it's still a major deal. The amp's chassis, real wood base, power transformer, PC boards, and even that nifty little Bottlehead badge are all made in the U.S.A. The Crack is a bit bigger than most desktop amps--it's 7 inches wide and 11.25 inches deep--and it was designed by Paul Birkeland.

I first tried the Crack with my high-impedance Sennheiser HD 580 full-size headphones. I bought these at least 10 years ago, and played 'em with countless receivers and headphone amps, but the Crack took the HD 580's sound to the next level. The sound was pure and clear, but never hard or bright. That's what the best tube amps do, you hear more of what's going on in the music, minus the edge or false hyped "detail" of typical budget-priced headphone amps. The Crack delivers bona fide high-end sound.… Read more

The world's best headphone amplifier?

I've reviewed and auditioned a lot of headphone amplifiers over the years, but Red Wine Audio's Isabellina HPA LFP-V Edition stood out from the pack. The amp improved the sound of almost every headphone I used with it.

Priced at $2,500 the Isabellina is very much a high-end audio product. Designed and built in Vinnie Rossi's small factory in Durham, Conn., the headphone amp's elegant functionality belies its technical sophistication. Rossi started Red Wine Audio in 2005, and before that he worked on high-speed laser transmitters for Bell Labs.

The Isabellina is more than just a headphone amp; it features a spectacularly good digital-to-analog converter and a hybrid transistor/vacuum tube audio section. While the Isabellina can be run off an AC power outlet, it sounds best powered by high-current lithium iron phosphate (LFP) batteries. Rossi claims "The batteries use organic, phosphate-based material, providing an ideal combination of performance, safety, reliability and environmental friendliness...in fact, more so than any other rechargeable battery technology."

The amp's digital connectivity options include USB, Coax, and Toslink/optical inputs; there are no analog inputs. The Isabellina has analog outputs, so it can be used as a stereo preamplifier, with a separate power amp to drive speakers, or a digital-to-analog converter in a hi-fi system.

The Isabellina features old tech 16-bit, non-oversampling digital-to-analog converters. Rossi acknowledges the latest chips' specifications look more impressive on paper, but he thinks most of them (even some really expensive ones) sound "quite sterile and artificial" in comparison. The Isabellina will work with digital sample rates up to 192kHz, but it will only playback with 16-bit resolution. … Read more

Pump up your iPod's sound for $60

Gary Ali has hand-built well over 8,000 Portable Pocket Amplifiers since 2004. He now sells the Version 2 model, the PA2V2, for $60, and that price includes shipping charges (he's in Toronto). I chatted with Ali by phone yesterday, and he seemed like a really nice guy.

His site, Electric-Avenues.com, is basic in the extreme, and lacks the usual shopping cart buttons and simplified ordering instructions. It doesn't state the PA2V2's price, so that was the first thing I asked Ali about. He explained that he likes talking to his customers one at a time, … Read more

Can a portable amplifier improve an iPod's sound?

I've written about better-than-iPod-sounding music players before, but this is my first portable headphone amplifier review. The Todd The Vinyl Junkie Portable Slim amplifier ($349) really works and will take the sound of an iPod, or any portable player, to the next level. The amp's sleek chassis (4.2x2.7x0.4 inches) is nearly the same size as an iPod Classic. It's built in Dallas, and the case comes from Canada.

The Slim's rechargeable lithium ion battery provides 15 hours of playback time. It recharges in about 2 hours from a USB port or a USB … Read more

Will this 10-watt amplifier rock your world?

Tube amplifiers sound different, and in many ways better than solid-state amps. Describing what better sound sounds like is a highly subjective call. But you can't argue the fact that tubes are still being manufactured, legions of guitarists use tube amplifiers, and a fair number of audiophiles crave tube sound. The catch? Tube designs are more expensive to build and sell than solid-state components.

The Jolida FX10 tube amp ($450) breaks that rule and sells for less than your average mid-price receiver. Jolida was founded in 1995, and has been a budget audiophile favorite right from the beginning. One of my closest audiophile pals bought an early Jolida amp, and he still uses it on a daily basis. So in terms of value, the FX10 will likely be a better long-term investment than most receivers (I get e-mails every week from people asking about dumping their five- or six -year-old receivers).

The FX10 is prettier than Jolida's old designs. Blue LEDs light up the Russian-made EL-84 power tubes and 12AX7 small signal tubes in the glass case, so the FX10 looks especially cool at night. The brushed aluminum chassis and safety glass tube cover are a big step up from what you find on similarly priced receivers. My sample was finished in sky blue, but the FX10 is also available in silver or black. Build quality feels substantial, and the solid-metal, gold-plated speaker wire connectors are a good indication of that. There are two RCA inputs on the rear panel and a 3.5mm input upfront.

The amp comes with a remote control and an iPod hookup cable. The 12-pound unit measures a trim 8x7x7 inches; so it's small enough to fit on a desktop.

The FX10 is a 10-watt-per-channel stereo amp, but don't worry, it can play pretty loud. Bass-heavy reggae music from Ras Mek Peace played nice and loud over my Zu Essence speakers. The little amp wasn't lacking in power or oomph, so yes, 10 watts can drive the right speaker to a remarkably loud volume. Soundstage depth was really good, so each instrument and vocals sounded fully present. This is an extremely well-recorded CD, without dynamic range compression, and the FX10 handled that sort of demanding music without raising a sweat. … Read more

AMP to develop electric SUV prototype for OEM

AMP Electric Vehicles has announced that it's developing a mainstream SUV prototype for an automaker, but it didn't say which one. The obvious guess is GM since the Cincinnati-based start-up has developed conversion processes for a handful of GM vehicles, including the 2010 Chevrolet Equinox, the 2007-2009 Saturn Solstice, and Pontiac Sky. However, a GM spokesperson indicated that the company does not have any agreement with AMP.

AMP purchases cars from dealerships for customers (or customers can bring their own) and converts the vehicle to operate with an electric drivetrain. Using a custom lithium ion battery pack and … Read more