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Recent Audio Amplifier Articles

Why Audio Amplifiers Can Sound Different

Why Audio Amplifiers Can Sound Different

Amplifier "sound" is a divisive topic in the audiophile community. Some would claim that amplifiers have a sonic signature, while others state that all "well designed" amplifiers will sound the same when operating within their limits. However, even within the latter camp, it is accepted that amplifiers *can* sound different from one another. Why might that be the case? We've gotten some thoughts from Paul Ceurvels, Senior Electrical Engineer at Atlantic Technology. Be sure to check out our YouTube discussion on this topic as well and let us know what you think in our forum.

Paul Ceurvels, Senior EE at Atlantic Technology discusses his experiences behind the scenes to explain how amplifiers can sound different from one another. Do you think amplifiers sound different?

— March 10, 2015 08:00 in Audio Amplifiers

The Most Memorable Audio Receivers of the Last 50 Years

The Most Memorable Audio Receivers of the Last 50 Years

In this editorial we examine 10 of the most memorable audio receivers from the last 50 years. We cover everything from vintage two-channel to the more recent multi-channel surround AV receivers. We discuss the evolution from tubes to transistors, power ratings and the FTC, social, economic, and demographic changes that have occurred in America since the 1960’s and how this has impacted the receiver market. Our listing doesn’t necessarily reflect the “best” of the best but there is no arguing these selections certainly left a lasting impression. We look forward to hearing your comments and alternatives that you feel should have been included.

This article highlights the most memorable audio receivers for the last 50 years ranging from vintage two-channel to the latest in multi-channel surround sound. What are your favorite receivers?

— February 20, 2015 08:00 in Audio Amplifiers

The Sound of Audio Amplifiers: Can you hear a difference between Amps?

The Sound of Audio Amplifiers: Can you hear a difference between Amps?

Whether or not amplifiers sound different is a subject of ongoing controversy. There are sensible, well-informed enthusiasts and magazine reviewers who will swear to their many, obvious differences, differences that are—to them, anyway—almost as obvious and important as the differences between speakers. There are also just as many well-informed enthusiasts and reviewers who say that there are no meaningful differences in the sound of two properly-functioning, properly-performing amplifiers operating within their undistorted performance envelope. And there is a third contingent that opines that the in-situ application of different amplifiers with different speakers and other associated equipment and connectors can produce differences in the sound even though nothing in the system is misbehaving per se. We explore the technical reasons with Rod Elliot of ESP and also debate this topic on our YouTube channel as to why amplifiers can sound different. We’ll open up the discussion, put forward some factual information, relate a few anecdotal experiences and look forward to your responses.

This article explores the technical reasons why audio amplifiers can sound different. Audio measurements can help explain why things look different but audibility isn't always so cut and dry.

Rod Elliot,Steve Feinstein — February 18, 2015 08:00 in Audio Amplifiers

Audioholics Amplifier Measurement Standard

Audioholics Amplifier Measurement Standard

There has been much discussion on the major audio forums lately regarding A/V receivers and multi channel amplifier power output capabilities as well as their abilities to drive low impedance loads. Much of the controversy steams around the infamous "All Channels Driven Test" which simulates a best case test load in a worst case environment and by all intents and purposes an unrealistic real world scenario. As a result, we have come up with a standard for measuring amplifier performance that deals with various types of power tests as well as other metrics that directly affect sonic performance and how the amplifier can sound powering various types of speaker loads. Check out our new Youtube Video Amplifier Interview for some great insights!

This article discusses the Audioholics testing methodology for measuring amplifier performance in receivers and power amps. We discuss the relevancy of the measurements and how they can affect sound.

— June 05, 2014 15:00 in Audio Amplifiers

Amplifier Voltage Gain Explained – Matching Amp to Preamp

Amplifier Voltage Gain Explained – Matching Amp to Preamp

If you've ever glanced at the specifications sheet of an external amplifier, you may have noticed the term "voltage gain". In short, it is the degree to which an amplifier actually amplifies the input from the preamplifier/processor. Often overlooked by those unaware of its importance, this one parameter can have significant implications on actual performance when an amplifier is introduced into an AV system. Understanding the impact that different levels of voltage gain can have in your system can very well be the difference between poor sound and getting the most out of an external amplifier. Read more about amplifier voltage gain to ensure you properly match your amp and preamp to achieve maximum performance.

Interested in a separate amplifier? Amplifier voltage gain and sensitivity are important specs to know about. This article explains the concept to help identify how to match your amp to a preamp.

— April 29, 2013 18:30 in Audio Amplifiers

Slew Rate in Audio Amplifiers - What Does it Mean?

Slew Rate in Audio Amplifiers - What Does it Mean?

Ever wonder what slew rate was all about? No, it has nothing to do with how a drunk person slurs their speech. When reviewing the spec sheet of an amplifier, one potentially unfamiliar term you may run into is slew rate. There are a lot of gobbledygook explanations floating around the web which seem to misunderstand the basic premise, so we at Audioholics are here to clear the air. In short, slew rate has little to do with how an amplifier produces dynamics so much as its ability to effectively maintain output into higher frequencies. It is the rate of how quickly an amplifier can respond to a rapid change of input level. This is measured as a change in voltage with respect to time as can be seen in the main image of this article. We discuss how to calculate slew rate based on amplifier bandwidth and power and also discuss real world implications of the spec.

This article defines what amplifier slew rate is and its real world implications. We also show how to calculate an audio amplifiers slew rate based on bandwidth and power level.

— February 08, 2013 12:00 in Audio Amplifiers

The High Instantaneous Current Spec

The High Instantaneous Current Spec

We've all seen amplifier companies tout that their amps are "high instantaneous current". Using the very basic principle governing electricity called Ohm's Law (V=I*R), how could it be possible that 100 watt amp has "higher current" than another 100 watt rated amplifier? This very subject has come up on numerous audio forums including the Audioholics forum, and this article explores that topic as well as the history of how the term "high current" became popularized by some manufacturers. We do some basic calculations to illustrate just how nebulous this specification often really is.

We've all seen amplifier companies tout that their amps are "high current". This article explores that topic as well as the history of how the term became popularized by some manufacturers.

Dan Banquer — October 18, 2011 14:00 in Audio Amplifiers

How a Class D "Digital" Amplifier Works

How a Class D "Digital" Amplifier Works

Ever wonder how an amplifier works at a very fundamental level? Alan Lofft, Resident Expert of Axiom Audio takes us on a tour of traditional linear amplifiers as well as the newer more sleek Class D designs. Various types of Class D design approaches are discussed including feedback topologies and their implications on audio performance and efficiency. The similarities and differences of traditional Class D amplifiers compared to Axioms new A1400-8 multi channel amplifier is reviewed. Learn what makes these amplifiers tick and why it’s cool in more ways than one to get your hands on the future of high end audio amplification that is powerful, efficient, and lightweight compared to their analog predecessors.

Ever wonder how an amplifier works at a very fundamental level? Alan Lofft, Resident Expert of Axiom Audio takes us on a tour of traditional linear amplifiers as well as the newer more sleek Class D

Alan Lofft — May 07, 2009 23:05 in Audio Amplifiers

Attack of the Clone Amplifiers

Attack of the Clone Amplifiers

It’s been a few years since our controversial release of “Attack of the Clone Processors” and we felt it was time for a sequel to our blockbuster hit editorial. Engineering a product from the ground up, especially one as complex as a switching amp, takes time and money with the end result often not being as good or cost effective as what can be bought off the shelf like these ICE modules from Bang & Olufsen. I can count the number of manufacturers producing their very own Class D designs and still have a finger left to point at all the copycats. Overall this seems to be a good design approach for manufacturers unwilling or unable to do their own developmental work if cost and full disclosure of performance is kept in check. It’s up to you the consumer to decide if paying a premium price for name brand, exotic accessory parts and cosmetics is worth the investment. Just don’t let anyone tell you that regardless of price, you are buying anything other than a clone amplifier, albeit a reasonably well engineered one.

It’s been a few years since our controversial release of “Attack of the Clone Processors” and we felt it was time for a sequel to our blockbuster hit editorial. Engineering a product from the

— April 28, 2009 21:15 in Audio Amplifiers

The Truth About Amplifier Power Ratings

The Truth About Amplifier Power Ratings

Ever wonder why the boom box you bought at Best Buy has a higher power rating than your dedicated two-channel power amplifier? Amplifier power ratings are usually honest in Hi-Fi equipment, but become very silly when it comes to the 'mass market' systems and even some of the latest Class D amplifier offerings. Few amps have a dynamic headroom of better than 1 or 2dB, and the greater the headroom, usually the cheaper the power supply for the rated power. This article explores the history of power ratings for consumer audio and also busts the myth about 'RMS' power.

Ever wonder why the boom box you bought at Best Buy has a higher power rating than your dedicated two-channel power amplifier? Amplifier power ratings are usually honest in Hi-Fi equipment, but

Rod Elliot — April 27, 2009 23:06 in Audio Amplifiers

10 Things about Audio Amplifiers You've Always Wanted to Know

10 Things about Audio Amplifiers You've Always Wanted to Know

Alan Lofft, Axiom Audio's Resident Expert, took a series of the most commonly asked questions he received about amplifiers, and transformed his answers into an informative editorial. In this article you will find answers to the importance of amplifier weight and how it relates to quality, how an amplifier works, what the different classes of amplifiers are (ie. class A, A/B, D, etc), and the most important attributes of amplifiers that govern their real world performance.

Alan Lofft, Axiom Audio's Resident Expert, took a series of the most commonly asked questions he received about amplifiers, and transformed his answers into an informative editorial. In this article

Alan Lofft — September 18, 2008 14:40 in Audio Amplifiers

The All Channels Driven (ACD) Amplifier Test

The All Channels Driven (ACD) Amplifier Test

Can Your Amp Truly Deliver What It Claims? Just how valid is the All Channels Drive (ACD) power test that many home theater publications use to measure amplifier power? This article cuts through the nonsense of this hotly debated (and often misunderstood) topic. We explore exactly how print magazines and manufacturers are rating their amplifiers power output with all channels driven, the relevancy of these tests and how it impacts real world performance.

This article explores the All Channels Driven power test popularized by some print magazines and manufacturers. It discusses its relevancy and real world implications.

— July 17, 2006 19:00 in Audio Amplifiers

Switching Amplifiers: The Technology and the Issues

Switching Amplifiers: The Technology and the Issues

This article started because a good friend of mine dropped a Panasonic SA-XR50 switch-mode amplifier to me for some basic bench test. This article will NOT be a review of that unit, but an investigation into some of the issues that are happening with this technology.

This article started because a good friend of mine dropped a Panasonic SA-XR50 switch-mode amplifier to me for some basic bench test. This article will NOT be a review of that unit, but an

Dan Banquer — April 09, 2006 20:00 in Audio Amplifiers

Switching Amplifier (Class D) Basics

Switching Amplifier (Class D) Basics

Just today I read on an internet forum a post by a "hot" new manufacturer of class D amplifiers saying that "the only way to solve the interference problem is to put the amplifier in a completely sealed metal enclosure". Apparently they were trying to excuse the fact that their product renders any nearby tuners useless. This begs the question: why didn't they do so then? Answer: because it doesn't help.

Just today I read on an internet forum a post by a "hot" new manufacturer of class D amplifiers saying that "the only way to solve the interference problem is to put the amplifier in a completely

Bruno Putzeys — March 01, 2006 19:00 in Audio Amplifiers