What is THD%??

[Ninkumpoop]

I'm looking to buy an amp and was wondering if that's what the amount of distortion is for the amp. If so, how much is an acceptable amount??

 

[Ninkumpoop]

*bump*

Anybody got an answer?

 

[kvndoom]

People sleep at night.

Anyway, it's one of the specs to look at when buying an amp. It's also one of many that can be twisted to make a bad product look good.

You want to see THD at rated power... if memory serves, anything over 1% is unacceptable and will sound like s***. Some list their 1-watt THD which is about as meaningless a spec as "max power"

 

[lovswr]

People sleep at night.

Anyway, it's one of the specs to look at when buying an amp. It's also one of many that can be twisted to make a bad product look good.

You want to see THD at rated power... if memory serves, anything over 1% is unacceptable and will sound like s***. Some list their 1-watt THD which is about as meaningless a spec as "max power"

Actually anything above 0.01 (that is ten 1 hundredths of a percent) is unacceptable. Also make sure the power is RMS or Root Mean Square or all channels driven.

 

[J-Speed Inc.]

I've installed many amplifiers in previous cars and have a JBL 600-watt amplifier installed in the J-Speed Inc. Mazdaspeed 3.

THD is the first thing I look for in terms of specs when shopping for an amplifier. I look for amps that have THD rating of .01 or better. The equipment you will find at Best Buy or other retail electronic stores typically will be 1%-5% THD which sounds pretty poor. Take a look at www.crutchfield.com, while their prices are high for electronics, they have a good amount of information on amplifiers.

Hope this helps!

 

[car46999]

Thd

Since you got 3 other opinions I thought I'd add another. The THD rating means Total Harmonic Distortion, which at it's rated power is how much the input signal is being distorted through amplification.
Less it better, but it depends on application, Such that subwoofer amplifiers "can have" more distortion. Without a human hearing it.

So my personal choice for amplifiers is: less than .01 for mids and highs, and less than .1 for subwoofers.
Older amplifiers from the 80's and 90's are my weapons of choice. (rockon)