GT 45

Often overlooked subtle, warm, musical phaser

 

   

 

The GT 45 phaser rack effect module compares to the MXR Phase 45, a good 70's phaser that was overshadowed by EVH and the Phase 90.  

 

Description

MXR released the Phase 90 and Phase 45 phaser pedals in the '70's.  The main difference is that the P-90 has 4 phasing stages while the P-45 has only two stages.  As a result, the P-90 has a lusher, wetter, deeper phasing sound than the P-45.  Some think the lusher phasing was a bit too much and in-your-face, while the P-45 is more subtle, and perhaps more musical, since there is less mangling of your notes.  Both are great for their intended purposes.  Of course, EVH soon began using the P-90 for his phasing, and then the '80's came along, a time for over-the-top modulation effects.  The P-45 languished in the shadow of the more famous P-90 jet swooshes and trippy ambiance.

The GT-45 compares to the MXR Phase 45 that went out of production years ago but was revived with a custom shop reissue.  Both the originals and custom shop reissue are great phasers.  With only 2 stages, the GT 45 isn't going to get you into the lush, deep, spacey phasing of '80's pop.  It is more subtle than that.  At low speeds, it might be an always on effect to give you a little something-something going on in your blues, country, or classic rock.  Maybe add a little touch of Waylon or Keef to your tone if you're stuck in the same 'ol, same 'ol, and need to switch it up a bit.

The Phase 90 and Phase 45 pedals came with only one control - Speed.  It doesn't get much simpler than that.  In their stock forms, they do that one thing, and do it pretty well.  But with a simple mod or two, you can get a much wider range of use from them, still within the bounds of their original effect.  Most modulation effects have a Depth control to control the intensity of the modulation, in this case, phasing, regardless of the Speed.  That is very useful.  In a sense, that's sort of the main difference between the P-90 and P-45 - different intensity of phasing.

Another popular mod for phasers is to provide a switch so that their standard phasing capacitors can be switched to the carefully mismatched capacitors that make the Univibe the hot spacey mess that it is.  The Univibe is a 4-stage phaser, so you can't get the full effect by switching caps in a 2-stage phaser, but it does provide a very nice and usable voicing that might be considered a Univibe lite.

Phasers mix the phased signal back into the incoming dry signal, usually at a 50-50 mix.  Adding a Mix control lets you adjust the mix, another different way of adjusting the intensity of the effect.  The Mix control goes from all dry signal at one end, to full phaser in the middle, to a subtle vibrato-like effect at the other end.  Not a must have, but a small change-up.  The vibrato is very subtle with the Speed or Depth turned back and is still relatively mild with Speed and Depth turned up.

The difference between the GT 45 and GT-90 is mostly just the hyphen in the name.  Well, OK, there's a little more to it than that.  Think of the GT-90 as going from almost completely dry, no phasing, to deep and lush phasing, and all points in between.  The GT 45 starts at the same almost completely dry no phasing point.  But it doesn't go as far into the deep and lush phasing.  As you adjust the GT 45 controls, you effectively have better control over its more subtle range of phasing.  That same range of phasing is available in the GT-90, but in a smaller portion of the control's range.  

 

Configurations

  • GT 45 - compares to the original MXR Phase 45 and custom shop reissue

    

 

Options

  • Depth Control - Add the usual modulation LFO Depth control to adjust the depth of the phasing effect.  Recommended.
  • Mixer Control - Adjusts the mix levels of the phasing effect and the dry signal.
  • Vibe Switch - Switches between standard P-45 phasing and a sort of a Univibe lite effect
  • External Bias Control - This is unlikely to be needed.  It may be useful if you have the Vibe Switch option and you want to tweak the phasing vs vibe bias for the JFETs.  Normally the bias is internal.
  • Speed Indicator - Add an LED that blinks in time with the phasing

 

Front Panel

  • On/Off indicator LED
  • Speed
  • (optional) Depth control (recommended)
  • (optional) Mixer control
  • (optional) blinking Speed LED
  • (optional) Bias control
  • (optional) Vibe switch

 

Rear Panel

  • Audio In
  • Audio Out
  • On/Off Footswitch
  • On/Off Override
  • DC Power
  • DC Power LED

 

Module Width

  • 1.5" standard 
  • 1.5" or 2" with options
  • 2" left wing and 1.5" right wing available for some configs

 

Power Consumption (aprox)

15-20 mA

 

Base Configurations

Part # Description List Price
MOD-GT45 GT 45 Module $220

 

Options

Part # Description List Price
MOPT-GT45-DEPTH Depth Control $19
MOPT-GT45-MIXER Mixer Control $19
MOPT-GT45-VIBE Vibe Switch $19
MOPT-GT45-BIAS External Bias Control $19
MOPT-GT45-LED Speed Indicator $10