"sweep" which moves the phaser's frequency response, yielding the classic phaser "whooshing" sound. The user can switch to 6-stage mode to produce a subtle change in harmonic response. The user can also control the phaser's resonance, changing the height and sharpness of the phaser's frequency response peaks. Like the MF-102, the MF-103 has an independent LFO, however in this instance it is used to vary the "sweep" parameter. In addition to a normal audio output, the MF-103 had 2nd Auxiliary output that was fed by an inverted instance of the Phase shifted signal. By utilizing both outputs in Stereo, some parts of the sound spectrum would be coming from one speaker and other parts would be coming from the other speaker. As the LFO modulates the phaser, the sound takes on a swirling spacial effect. The MF-103 was released in 1999. MF-104 The MF-104 is a completely analog delay. The effect allows the musician a delay time between 40 milliseconds and .8 seconds. However the most remarkable feature is the use of an internal/external feedback loop. The feedback loop from the MF-104 can be routed through another effects processor and back into the delay unit, allowing processing of the echos as they are being generated. As with most analog delay processors, a desirable warmth of sound is created by the increasing natural decay of the original audio signal through the continuation of echoes. Released in 2000, the MF-104 was manufactured in a limited edition of 1000 units. A special "bucket brigade delay chip" was employed to allow the effect to be completely analog; however, the supply of these chips was limited. The final units were sold in 2001 and the MF-104 Analog Delay remains the most sought-after of the moogerfoogers. In 2005, Moog Music announced the planned re-release of the MF-104, dubbed the MF-104Z. The new pedal will have the same functions as the original, but will feature a longer possible delay time (slightly longer than 1 second). At the same time, the MF-104SD was released in a limited edition of 250 units. The MF-104SD had a maximum delay time of 1.4 seconds, slightly longer than the MF-104Z. In June 2012, Moog Music Inc. released the fourth and final version of their Moogerfooger Analog Delay, the MF-104M. The new MF-104M Analog Delay utilizes the same vintage Bucket Brigade chips found in the Classic MF-104. In addition, the MF-104M includes a