Introduction to Amplifier Reviews

Amplifiers can be considered in three subcategories: Preamplifiers, Integrated Amplifiers and Power Amplifiers.

Preamplifiers handle small signal switching and gain or attenuation (volume control). In many cases, these products have balance controls, equalization or even automated room correction. Preamplifiers may also contain phono preamps, DACs, video switching, headphone amps and streaming/playback of digital files to name just a few additional features you may encounter. There are several different circuit topologies on the market, some are quite simple and others very complex. Preamplifiers do not have amplification to drive speakers and for this purpose you will need to add a separate power amplifier.

Integrated Amplifiers : take a preamplifier, add a stereo amplifer in the same chassis and you have an integrated amplifier. Though more convenient, this is widely regarded as less desirable than having a separate preamplifier and power amplifier as this isolates the small and large signal sections far better than with integrated amplifiers. Integrated amplifiers can have all the features of preamplifiers. They are also available in solid state, vacuum tube or hybrid designs.

Power Amplifiers provide the power to drive your passive loudspeakers. Like all the other amplification components, they can come in a variety of styles. It is of the utmost importance to select an amplifier that is compatible with your speakers and with sufficient power to fill your room with music.

All our reviews feature breakdowns of the product design, product setup and notes on the performance with subjective listening impressions. Most of our reviews also include our own objective bench tests which tell you how much distortion an amp has, its frequency response and, in many cases, its maximum power output, irrespective of manufacturers' claims.

Review Categories

Preamplifiers

Wireless Amplifiers

Integrated Amplifiers

Power Amplifiers

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Amplifier Reviews

Mystere ca21 Stereo Tube Preamplifier

John E. Johnson, Jr.

Following on our recent review of the Mystere pa21 stereo tube power amplifier, we now review the matching preamplifier, the ca21. It is a single gain stage design, with only one buffer and one capacitor in the signal path. It is as beautiful as its brother, and sounds great as well. Read on.

Preamplifiers

Lamm LL1 Signature Stereo Tube Preamplifier – An Audiophile’s Dream

John E. Johnson, Jr.

Lamm introduces their LL1 Signature preamplifier, which is the partner to their ML3 Signature power amplifier. Both the LL1 and ML3 are cost-no-object products using only the finest parts that can be found anywhere in the world. The design is based on Vladimir Lamm's 50 year career in design of tube components that perform at the extreme limits of sonic perfection. The LL1 is a $43,000 four-chassis, 114 pound, state-of-the-art masterpiece.

Preamplifiers

Mystere pa21 Stereo Tube Power Amplifier

John E. Johnson, Jr.

Durob Audio is a company in the Netherlands that markets PrimaLuna tubed audio components, including integrated amplifiers, power amplifiers, and a CD player that has a tube-based clock. It also has a discrete output stage with triodes running in pure Class A. Conventional CD players use op-amps in the output stage. Although the tube output stage and op-amp output stage sound different, one doesn't necessarily sound "better" than the other, although tubeophiles would all opt for the "better". We reviewed the PrimaLuna DiaLogue Two integrated amplifier in December, 2009.

With the introduction of Durob Audio's Mysterè line, we now review the Mysterè pa21, which is a 55 watt per channel stereo tube power amplifier. The Mysterè line goes beyond the PrimaLuna line with larger transformers, more power supply capacitance, and an auto-bias circuit that lets the consumer choose between using KT88's or EL34's as the output tubes.

Power Amplifiers

Emotiva UPA-5 Five-Channel Power Amplifier

Chris Heinonen

Over the past decade, a lot has changed on receivers that we buy for home. We've gone from S-Video to Component to HDMI for video, replaced 6 RCA cables for 5.1 audio with a single digital cable, to having it integrated in the HDMI signal along with video. Receivers have added all sorts of new functions with better on screen menus, room correction, Ethernet ports for streaming media and firmware upgrades, and we have also moved from 5.1 channel audio, to 6.1, then 7.1, and now all the way to 9.1 or greater when using Dolby ProLogic IIz or Audyssey DSX. However, one thing on receivers has barely changed when I look back over the spec sheets: weight.

Power Amplifiers

EMP Tek VT-40.2 Hybrid Integrated Stereo Tube Amplifier

Jim Milton

Engineered Music Products (EMP) was founded in 2007 by industry professionals with over thirty years experience in designing, engineering and manufacturing high-performance loudspeakers for companies such as ParaSound, McIntosh, JBL, Destination Audio and Fosgate. EMP Tek is a sister company of speaker manufacturer RBH Sound. For years I have heard people talk about tubes ("valves" if you are British) and how warm and wonderful they sound. This is my chance to hear for myself. Can one find analog bliss in a digital world?

Integrated Amplifiers

Lamm LL2.1 Stereo Tube Preamplifier

John E. Johnson, Jr.

Lamm Industries has been a venerable brand name in high end audio for decades. They build each product when it is ordered, so you won't see a bunch of any particular model "in stock" anywhere. Their specialty is tube-based preamplifiers and power amplifiers, with their top-of-the-line power amplifier selling at well over $100,000. The current review focuses on the model LL2.1 stereo preamplifier. At $5,995, it is the most affordable preamplifier in the Lamm product line.

The LL2.1 is an updated version of a previous model. Several new features have been added along with modifications of the basic circuit.

Preamplifiers

Bryston 9B SST2 Multi-channel Amplifier

Jared Rachwalski

Bryston is known for building some of the most sought-after, powerful and dependable amplifiers in the business. For over 40 years, they have provided an incredible 20 year transferable warranty, practically unheard of in this or any industry. If you find one (that is if you can find one) on the used market, chances are it will still be under warranty. Their rare appearance on the used market has as much to do with their sound quality and dependable (high) power delivery as it does with their warranty. Here, we review their 9B SST2, which is a five-channel (5 x 140 watts) power amplifier.

Power Amplifiers

PrimaLuna DiaLogue Seven Tube Monoblock Power Amplifier

John E. Johnson, Jr.

PrimaLuna is a Dutch-based company that released its first products, the ProLogue One and ProLogue Two integrated tube amplifiers in 2003. Then, in 2006, they released the ProLogue Three preamplifier, and ProLogue Five, Six, and Seven power amplifiers. Late in that same year, the PrimaLuna DiaLogue series hit the market, which had the DiaLogue's basic features, but with upgraded parts and additional capabilities. Here, we review the DiaLogue Seven, which is a monoblock power amplifier, capable of delivering 40 watts RMS in triode mode, and 70 watts RMS in ultra-linear mode (see review for an explanation of what this means). The bottom line is that the PrimaLuna DiaLogue Seven monoblock is more than capable of delivering a clean, detailed, and lush sound (ah, those tubes are responsible for that).

Power Amplifiers

PrimaLuna DiaLogue Two Stereo Integrated Tube Amplifier

Rick Schmidt

The PrimaLuna brand needs no introduction to the tube-loving community, but I do (did). Though I've heard plenty of good sounding tube gear at shops, at various friends' houses and of course at shows, I generally listen to solid state equipment. So, having the PrimaLuna Dialogue Two here for review was a new, and very pleasant experience.

Integrated Amplifiers

McCormack LD-2 Preamplifier and DNA-250 Stereo Power Amplifier

Jim Milton

In 1997, McCormack Audio was purchased by Conrad-Johnson, known primarily for their fine tube amps and preamps. They have the same high quality and value that Steve McCormack put into his designs in California, but these current products are basically an entirely new line (and are built in Virginia). In this review, we take a look at one of their line-stage preamps, and a stereo (two-channel) power amplifier.

Preamplifiers

Emotiva USP-1 Stereo Preamplifier

John E. Johnson, Jr.

Emotiva's new USP-1 stereo preamplifier, at $399, sets a new standard in performance in low priced components. Besides the standard full range outputs, this preamp offers a split output where you can adjust the low-pass frequency for one (which goes to your subwoofer) and the high-pass frequency for the other (which goes to your main power amplifier). This allows you to essentially bi-amplify, and with the low frequencies removed from the high-passed output, your power amplifier will run more efficiantly, not having to waste power on low frequencies that your speakers cannot reproduce. And, they toss in a phono stage that has both MC and MM settings. This may mark the beginning of phono stages being a standard part of stereo preamplifiers, rather than having to purchase an outboard phono stage. Long live LP's! Oh, there's a headphone jack too.

Preamplifiers

Bryston 4B SST2 Stereo Power Amplifier

Kevin Lichterman

Bryston Ltd. is a Canadian company which has been designing and manufacturing audio equipment for over 35 Years. While there are many companies competing in their market, Bryston's gear is coveted by enthusiasts and professionals alike. They have earned the reputation of providing bullet-proof reliability, high performance and value. Byston's value is not due to a bargain basement price. It's the sound and their 20 year guarantee of high performance that can make a Bryston purchase a value. This remarkable warranty speaks to Bryston's confidence in their own quality standards, and it is definitely the exception versus the rule in the A/V industry.

Power Amplifiers