Yamaha DX7 Product Manual - Page 34

The "current" operator is that one whose parameters are being displayed, and which is ready to be reprogrammed. You can see which one is current (OP1 through OP6) by looking at the upper right hand comer of the LCD display A"?" is illustrated here because we don't know which operator is current (that is not reset by the VOICE INIT function). 2. Press [OPERATOR SELECT] as many times as necessary until the upper right corner of the display shows OP1; if OP is already displayed, you can skip this step. This envelope, with all maximum levels (except Level 29 4) and maximum rates defines a "square" envelope that turns on to maximum level the instant you press a key and turns off completely the instant you release the key If you could see the envelope, it would look like this: This is what the "initialized" envelope would look like if you could see it. You can hear it, though. ALG1 1 1 1 1 1 1 OP1 EG LEVELS =99 ALG1 1 1 1 1 1 1 OP1 EG LEVELS =99 NOTE At this point, operator 1, a carrier, is the only operator contributing to the sound because the output levels of operators 2 through 6 were set at zero when ALG1 1 1 1 1 1 1 OP1 EG LEVEL 4 = 0 you initialized the voice. If you were to play the key- boardwiththedisplayshowing"OP2"oranyother 4. Lets look at the 4 envelope rates. Press the [EG operator you would be hearing only operator 1. If you RATE] button, and the display will now show you were to then go ahead and adjust the envelope of an Rate 1. Press it 3 additional times to see the remain- operator other than OP1, you would not hear any- ing 3 rates. Both EG Rate and EG Level work like thing change because only operator 1 is contributing this, in a continuous cycle through the 4 available to the sound in the DX7's current status. This step, points. selecting the "current operator" to be OP1, is necessary so that you will hear the results of the adjustments we ask you to make in subsequent steps. 3. Lets just look at the 4 levels for this envelope without changing them. The display should already show you that Level 1 is set at 99 (the maximum), as illustrated above. Press [EG LEVEL] 3 additional times, examining the display each time you press the button. Notice that Level 1, Level 2, and Level 3 are all set at 99, but Level 4 is at zero. Normally Level 4 will be set to zero because if it is at a non-zero point the sound will not fall to silence when you release the key (A Level 4 value higher than zero is something like latching the Voltage Controlled Amplifier (VCA) open in a conventional synthesizer.) And watch the display Actually, since L1 and L2 and L3 are the same, R2 and R3 should be set to 99 here to avoid anomalies. This rate does not affect the "square" envelope; because the level does not have to change in this part of the envelope, the rate of change is inconsequential. R1 (where the sound first builds to L1) and R4 (where the sound falls to L4)dohaveaneffect, as we are about to demonstrate. Experimenting with the EG Now lets alter the initial envelope to cause the volume to gradually work up to the maximum (the L1/L2/L3 level), and then gradually reduce to zero (the L4 level) 1. Press EG RATE as many times as required so the display shows Rate 1 (it should be just once if you followed the previous instructions to the letter.) Then move the [DATA ENTRY] slider until the rate changes from 99 to 25, stopping several times to play the same note so you can hear the changes that recur at slower and slower rates. You may find it easier to press the [] buttons to precisely set the rate after using the [DATA ENTRY] slider to get close to 25. When you're done experimenting with Rate 1, leave it set at 25. NOTE The slower the rate, the longer it takes for the note to build to the maximum level. You can experiment with rates below 25, but you'll have to wait a long time for each note to develop. \Vhen Rate 1 is 0 and Level 1 is 99, the sound will take about 40 seconds to reach maximum intensity;