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's Class T amps have developed a strong following for one really good reason: people really love the sound. The DTA-1 puts out 15 watts a channel and has a mini 3.5mm analog input jack on its rear end. It's also nice and little, just 2 inches by 6.3 inches by 3.3 inches. The DTA-1 T-amp can run on 8 AA batteries or the included power supply.
Electric Avenues PA2V2 Portable Headphone Amplifier ($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). You can use the amp with a laptop, TV, radio, iPod, MP3 player, or gaming system. I used the PA2V2 running off my iPod Classic's line-out multipin connector, with a CablePro Right Angle iPod Dock to 3.5mm plug. It sounds amazing for the money!
NAD 3020 Integrated Amplifier (used prices range from $50-$300)
I recently bought a 31-year-old NAD 3020 integrated amplifier on eBay for $66. It was rated at just 20 watts per channel into 8 ohms, but it can deliver as much as 58 watts into 4 ohms, and 72 watts into 2-ohm speakers! I doubt any of today's $1,000 receivers can handle low impedance (4 or less ohm) or difficult to drive speakers as well as the 3020 can. It has a terrific-sounding phono preamplifier, so the 3020 is ideal for serious vinyl buyers on a budget.
Sherwood RX-4105 Stereo Receiver ($120)
Yes, they still make stereo receivers. This 100-watt-per-channel receiver won't wow you with an overstuffed features list or a dazzling LCD display, but it seems well-built. It weighs nearly 20 pounds, more than most $300 5.1 channel AV receivers with the same power rating. You might wonder how that can possibly be, but the answer is simple: the AV receiver manufacturers are overly optimistic about their power ratings. Amazon currently sells the Sherwood for $91.77.
Topping TP30 Headphone & Speaker Amplifier ($129)
The Topping TP30 isn't just a headphone and speaker amplifier, it also sports a built-in USB digital-to-analog converter! The amp delivers 15 watts per channel to 4-ohm-rated speakers (10 watts into 8 ohms), and has a 3.5mm headphone jack on the front panel. With its extruded aluminum chassis, thick machined front panel, and solid-metal volume control knob, the TP30 wouldn't look out of place in a high-end desktop system. I use this one on a daily basis.
Bottlehead Crack Headphone Amplifier ($219)
The Bottlehead Crack Headphone Amplifier is an awesome-sounding vacuum tube design. Not just good for the money; if it was four or five times as expensive, I'd still love the sound. The $219 price is for the build-it-yourself kit version, which is the way most people buy them. Bottlehead also sells assembled Cracks for $369.
Onkyo TX-8255 Stereo Receiver ($249)
Rated at 50 watts per channel, the TX-8255 sports "A" and "B" speaker output connectors and can handle difficult to drive 4-ohm rated speakers. If you're getting into vinyl, the TX-8255 has you covered with a phono preamp. Hook up a turntable and you're good to go. Amazon sells Onkyo's TX-8255 stereo receiver for $155.
Dynaco ST-70 Tube Power Amplifier (used prices range from $300 on up)
Designed by David Hafler in 1959, the stereo 35-watt-per-channel tube amp is legendary for its sound quality. It sold in huge numbers, so it's not all that hard to find working ST-70s today. The design is easy to modify; a lot of surviving units have been done over. If you want classic tube sound on the cheap, a Dyna Stereo 70 would be a good place to start. I owned one in the 1980s and really loved it.
Denon AVR-1712 AV Receiver ($399)
The Editors' Choice Denon AVR-1912 receiver is a wee bit too expensive to fit in here, so I opted instead for the very similar AVR-1712. Both receivers are loaded with features, so if that's a biggie for you, and still want decent home theater sound, pick up one of these Denon receivers.
Jolida FX10 Integrated Tube Amplifier ($450)
It may be just a 10-watt-per-channel stereo amplifier, but with the Jolida FX10's blue LEDs lighting up the EL-84 power tubes and 12AX7 small signal tubes in the glass case, the little amp looks especially cool at night. The brushed aluminum chassis and safety-glass tube cover are a big step up quality-wise from what you find on similarly priced AV receivers. And with the right speakers, the sound will be a lot more musical than what you'll hear from a receiver. Ten watts can surprise you.