AE 282: Spring 2005

INSTRUCTOR: Eddie Ciletti

WEEK-7 Review: Tube Distortion, M-S Techniques, Loudness Issue, Tube / Ref Link-1, Tube-Link-2

Re-amp, sum and difference

The class focused on guitar amps and distortion. There are two types of power amp designs, single-tube Class-A (Fender Champ) and Class AB (even number of power tubes, typically 2 or 4).  The demonstration made obvious that over driving a class AB power amp is better for lead than rhythm guitar.  Class-A delivers a sweeter sound comes from either overdriving the front end - what a MASTER VOLUME CONTROL does - or the power amp.

Amps equipped with an OUTPUT IMPEDANCE SWITCH can be fine-tuned to optimize distortion.  CLICK HERE to see images of how the SOUL-O amp responded...

The Groove Tubes SOUL-O Single is essentially a Fender CHAMP on steroids,.  Featuring a single output tube (6L6 for the demo), the amp is designed to accomodate just about any tube that will fit in the socket, including the following:

  • EL84 (with adapter)
  • 6V6
  • 6L6
  • EL34
  • KT66
  • KT88
  • 6550

WEEK-8's assignment is to configure PT to allow sum and difference analysis and processing of a stereo mix.  You are encouraged to do this in advance and bring your session files to class. CLICK HERE for a quiz that will jog your memory of other topics discussed in week-7's class.

Keep in mind that when extracting and reconstituting the M-S audio files in the digital domain, it is important to keep track of LATENCY, the delay caused by any process. For example, if you apply EQ to the sum, you must also apply EQ to the difference, even if bypassed.  You will notice that delays in either  signal path will change the stereo image, sometimes in interesting ways.

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