tim@fisher.UUCP (Tim Snyder) (01/23/86)
> discussion with a salesperson. They tell me that splitting the > DX7 is not easy. What I want to do is program the left side of the > split for bass and the right side for all the other stuff. The > > Thanks, > Frank D. LaRocca > homxa!fdl > 201-536-0582 Briefly (and simply, for the uninitiated): The DX-7 uses "algorithms" composed of "operators" to form its sounds. An operator can be either a "carrier," which is an actual sound produced by the algorithm, or a "modulator," which modulates or "wiggles" a carrier's sound. Many of the algorithms have more than one carrier, (two to six) hence can produce two very different tones simultaneously. The DX-7 has no DISCRETE split. One uses "scaling" to achieve this as follows. First, an algorithm such as the one mentioned above is chosen and the two required tones are programmed to two carriers. Second, an arbitrary breakpoint is chosen. Third, the two carriers are scaled so that one essentially appears only to the left of the breakpoint, while the other appears only on the right. The scaling is done as follows. Before any scaling is done, a carrier is uniformly activated by the entire keyboard, hence both sounds will occur simultaneousy over the entire keyboard. To place a given carrier (say the one doing bass) to the left of the breakpoint, one chooses to assign a negative "curve" to the portion of the keyboard to the right of the breakpoint. Either an exponential or linear curve can be selected. The linear one is used to achieve a split, and its value is maximized so that the carrier's sound dies away rapidly to the right of the break- point. Similarly, the other carrier is made to disappear to the left of the breakpoint, giving the desired split. Since the split is not discrete, there is a "fuzziness" near the break- point, i.e., a bit of, say, brass might occur to the immediate left of it and some bass might be heard to the immediate right. I don't find this to be a problem since only a few keys are affected, i.e., one can make the carriers die away damn quickly if necessary. In terms of the difficulty of doing this, it is no more so than programming the instrument, which many find not so easy. Given the unbelievable range of capabilities, however, the programming is a relative snap. Also, since you are dividing an algorithm's carriers to produce two sounds instead of one, you will not have the richness you would have when using that algorithm to produce a single tone. One does not have to start from absolute scratch. You can take ideas from your favorite bass patch to form your bass portion of the algorithm, etc. If you are doing bass all the time, though, it will take a while to get rolling since you will have to "borrow" carriers from the patches you wish to use on the right side of the breakpoint. Yes, a TX-7 will help. In addition to giving you the astounding sound and flexibility of virtually two DX-7's, it will eliminate the problems mentioned in the prvious two paragraphs. BEFORE YOU BUY: Find a knowledgable salesperson (one who owns and uses the instrument for such things) to show you what is gained and what is lost when doing this. My feelings on the instrument: ...on the order of erections and coronaries....MONSTER! Best of luck, Tim Snyder princeton!fisher!tim or princeton!tilt!tim