Flushing Out Myths In Consumer Audio

Being a consumer in such a vast and complex field as consumer audio and video can be frustrating for neophytes looking to increase their knowledge base in hopes of making educated purchasing decisions. Marketing can often be a big hindrance in differentiating the truth from hyperbole. More often than not, consumers will be drawn into the marketing literature much like a moth is to light but often don't consider that a flame can burn if you get too close. We of course always recommend keeping at safe distances from hot flames and always to make sure you have a source of water close by incase of emergencies. In the meantime, we have collected a list of articles relating to myths surrounding audio which we hope will serve as a first aid kit and extinguisher against the hot air you may succumb to from the sales person when visiting your local hifi shop.

Cable Myths

Q: Do I have to keep my cable lengths the same?

A: No you don't. Please refer to Speaker Cable Length Differences, Do they Matter?

Q: What is Skin Effect and is it an issue with Speaker Cables?

A: Skin Effect is a phenomenon of predominant concern for RF applications and has little to no meaningful relevance at audio frequencies. See: Skin Effect Relevance in Speaker Cables

Q: Do cables really break in?

A: No. Cable break in is a myth to convince consumers to keep the cables for longer than the return period. See: Cable Break In

Additional Recommended Reading Materials:

Top Ten Signs a Cable Vendor is Selling you Snake Oil

The Truth About Interconnects and Cables

Amplifier Myths

Q: How relevant is the All Channels Driven Test (ACD) for amplifiers?

A: Not very relevant at all. It's a worst case test condition into a best case test load. Most A/V Publications that run this test do so with a 1kHz instantaneous sweep of distortion vs. power while holding the line voltage constant with a VARIAC and often bypassing the amplifiers internal fuses to prevent them from blowing. Very few "Separates" amplifiers can truly deliver their rated power ACD on a continuous basis despite their marketing literature claims and the mostly non real world test results published in the magazine review you just read.

See: The All Channels Driven Amplifier Test Controversy

See: The All Channels Driven Forum Support Thread

Q: But my 400wpc x 7 linear amplifier I just purchased from XXX manufacturer states it can hit its rated power ACD.

A: Unless the amplifier had multiple independent line cords powering it, this is NOT a possible scenario. Let's do some basic math.

Wall Outlet: 120V, 15 Amps

Max available Power: 1800 watts

Typical Linear Amp Efficiency: 40-50% Let's choose 45%

Max Available Power Delivery: 1800 x 0.45 = 810 watts

Max Continuous Power to 5 Channels: 810 / 5 = 162 wpc

Max Continuous Power to 7 Channels: 810 / 7 = 116 wpc

Please stay tuned for our up and coming article that goes into more detail about this topic.

Q: Is it important to have an amplifier with a high damping factor?

A: Damping factor is a somewhat nebulous metric for amplifiers since it can be measured and fudged and is largely dependent on speaker voice coil resistance.

See: Damping Factor Effects on System Response

Q: My receiver / amplifier boasts it can deliver Instantaneous High Current. Is this important?

A: This is another myth perpetuated by some manufacturers and audio elitists. While it's important for an amplifier to deliver large amounts of continuous current into low impedance loads, some manufacturers boast a high instantaneous current figure which is impractical to deliver to real world loads and mostly has little relevance in determining the robustness of the amplifier design.

See: The High Instantaneous Current Amplifier Spec

Q: The $199 100wpc receiver I bought at Kmart is just as powerful as the $1000 one sold at specialty shops.

A: This is most likely not true. Manufacturers often play games with power ratings and are almost never apples to apples comparison.

See: Product Managing Receiver Platforms

Q: I hear "digital" Switching Amplifiers are the future in audio. Is this true?

A: Yes and No. A switching amp (aka. Class D) can have significant advantages over conventional amplifier designs in terms of efficiency, power delivery, cost savings and performance. However, very few manufacturers are currently executing these designs intelligently and it's an ever evolving process to do them right. Stay tuned here as we explore the wonders and pitfalls of these new amplifiers.

See: Switching Amplifiers Technology & Issues

Loudspeakers

Q: Is Speaker Break In Real?

A: Kinda, but NOT in the sense most manufacturers and review publications would have you believe.

See: Speaker Break In Fact or Fiction?

Q: Bass Reflex speakers are MORE efficient than Sealed Enclosures.

A: This is another myth. See: Five Myths In Audio Dispelled

Q: Five Full Range Equidistantly Placed Speakers are Ideal for a Consumer Based Multi Channel Playback system.

A: Wrong! This type of scenario at best can be optimized for a single sweet spot / listening position and will usually result in compromised bass performance. The objective for accurate and high performance multichannel playback in a typical home is properly placed bass managed speakers with a multi subwoofer system.

See: Surround Panel Discussion: Setting a Surround Standard

Q: Series Crossovers are Better than Parallel Networks in loudspeakers.

A: This is a myth. Both crossover designs can be implemented to yield similar transfer functions though series designs are limited if high order filter responses are a desired design goal.

See: Series vs Parallel Crossover Networks

Recommended Additional Reading Materials:

Avoiding Loudspeaker Gimmicks

Understanding Loudspeaker Frequency Response

How to Judge Loudspeakers - Sound and Accuracy

Wireless Surround Sound Speakers the Future?

Loudspeakers: When Is Good Enough, Enough? (Part 3)

Loudspeakers: When Is Good Enough, Enough? (Part 2)

Loudspeakers: When is Good Enough, Enough? (Part 1)

Software Formats

Q: Oversampling & Upsampling will improve the fidelity of your CD's.

A: This is another myth popularized by audio elitists and some manufacturers. In most cases, this type of post processing will serve more as a hindrance and can usually result in more inaccurate playback artifacts including higher distortion, noise or loss of resolution.

See: Upsampling vs. Oversampling for Digital Audio

Q: Brickwall Filters in CD players cause phase deviations and artifacts in the audio band.

A: This is a myth. See: Brick Wall Digital Filters and Phase Deviations

Q: The CD format sounds harsh and isn't a high fidelity medium.

A: This isn't true. It's usually the recording process which causes excessive compression that is to blame for the lack of fidelity of most CD's.

See:

Current Trends in the Recording Format Arena P2

Current Trends in the Recording Format Arena P1

Dumbing Down of Audio

That's a Wrap

We hope this brief editorial with reference links to our articles helps to extinguish some of the myths surrounding consumer audio and video. We encourage you to do your research before visiting a local AV / HiFi shop and NEVER take marketing literature, salespersons advice, consumer or professional product reviews (including our own) at face value. Just remember NOT to panic. We've got your back. Oh yea, don't forget to flush, and NEVER travel the Universe without a towel.