; Distortion
Documents
Resources
Learning Center
Upload
Plans & pricing Sign in
Sign Out
Your Federal Quarterly Tax Payments are due April 15th Get Help Now >>

Distortion

VIEWS: 5 PAGES: 16

  • pg 1
									 A distortion is the alteration of the
 original shape (or other
 characteristic) of an object, image,
 sound, waveform or other form of
 information or representation.
Unwanted or wanted?
 BAD: Digital Clipping,
 distortion of CLEAN sounds


 GOOD: Guitar tube amp,
 tube outboard gear,
 Analog saturation
Clipping
 Clipping is a form of distortion that
 completely limits a signal above a certain
 threshold.

 This can occur in digital signal, or on digital
 equipment

 Is often a hard and harsh sound at the
 threshold
 Hard clipping results in many high
 frequency harmonics

 soft clipping results in fewer higher
 order harmonics and distortion
 components.
VACCUUM TUBE DISTORTION
 Some audiophiles believe that the clipping behavior of
  vacuum tubes is superior to that of transistors
 Vacuum tubes give a gradual ‘clip’ with comes off as
  overdriven harmonics
Hi-Fi Audio
 Audiophiles often use Tube Amplifiers:
Analog Distortion
 A circuit designer may intentionally use a clipper or clamper to keep a
    signal within a desired range.
   When an amplifier is pushed to create a signal with more power than it
    can support, it will amplify the signal only up to its maximum capacity,
    at which point the signal will be amplified no further.
   An integrated circuit or discrete solid state amplifier cannot give an
    output voltage larger than the voltage it is powered by (commonly a 24-
    or 30-volt spread for operational amplifiers used in line level
    equipment).
   A vacuum tube can only move a limited number of electrons in an
    amount of time, dependent on its size, temperature, and metals.
   A transformer (most commonly used between stages in tube
    equipment) will clip when its ferromagnetic core becomes
    electromagnetically saturated.
Digital Distortion
 In DSP, clipping occurs when it wants a
  VALUE higher than the given range
 It can’t go any higher than the
  maximum

 Remember 0 dbFS?
 It is completely clipped and distorted
T
h
Solutions for Clipping
 Leave HEADROOM: Space at
  the top
 (24 bit helps because of a lower
  noise floor)

 Use a LIMITER to compress
 instead of clip!
Frequency response distortion
 Simply when frequency response is altered
 in the signal chain

 Happens ALL the time. Sometimes can be
 wanted
Causes
 Room Acoustics
 Monitors/loudspeakers
 Audio Cables / long runs
 Outboard Gear
  Phase Distortion
 A more complex distortion
 It occurs in certain audio
  components
 This ties into Frequency Response
  Distortion

 For example: An amplifier amplifies
 signal at different levels in the
 frequency

								
To top