Psychoacoustics and high fidelity set aside, the mixing aspects of Flash in radio production do offer several pluses. If your studio has acquired additional pieces of outboard gear over the months or years, and you didn't have a large console to begin with, Flash makes for a nice, and very flexible, "sub-mixer." If you've added CD players and R-DAT machines but don't have enough inputs on your console, Flash is an ideal unit to expand your console with. These digital machines will retain their full quality while passing through the Flash to your console, and you'll have some very interesting mixing and switching options at your disposal.
As an audio switcher, we have yet to hear of a box that has the power of Flash. This is where the MIDI features of the unit come in. On the left side of the front panel are four buttons with accompanying LED's. You can switch from one input to the other and layer inputs using these four buttons, or you can send MIDI program change messages to Flash for MIDI control of the switching and layering. Using the buttons to switch and layer manually gives you up to sixteen different combinations to choose from -- input 1 with 3; 2 with 3; 1 with 2, 3 and 4; etc.. Using MIDI, you are given up to 256 different combinations. This is because, with MIDI, left and right inputs can be selected individually. For example, you could have a mix that is comprised of the left channel of input 1, both channels of input 2, and the right channel of input 3. Consider also that the four stereo inputs can also be treated as eight mono inputs going to two mono outputs.
Now comes the kicker. Let's say you have all four stereo inputs in use. With MIDI program change messages coming from a sequencer, Flash can switch from one input to another as fast as one hundred times per second, NOISE FREE! You can have, let's say, a stereo music bed going through input 1, and various sound effects going through inputs 2, 3, and 4. You can do a mix with the music playing steady while the sounds on inputs 2, 3, and 4 switch from one to the next to the beat of the music and have them bounce back and forth between the left and right channels. Think about that for a while and consider all the possibilities for some fun on a slow day. We played around with this for some time but had some difficulty getting the internal sequencer of an Ensoniq SQ-80 to shoot out program change messages as fast as the Flash could receive them. Nevertheless, we sent them fast enough to come up with some interesting results. It may have been lack of knowledge about the SQ-80's sequencer or limited abilities of the sequencer itself that prevented us from sending program change messages at a rate of one hundred times per second, but anyone with a computer based sequencer should have no problem getting things at full speed.
Also controllable via MIDI is the muting function of Flash. There's a mute button on the front panel that will noiselessly mute the output of the unit when pushed. When controlled by a sequencer, the Flash's output can be muted then turned back on at a rate of one hundred times per second. Done to the beat of a piece of music, you get an effect used on a lot of "Euro-disco" type of music.
With both the input switching and muting functions there are two "modes" of operation available, LATCH and PUNCH. When switching inputs in the LATCH mode, an input will turn on when the button is pushed and remain on until the button is pushed again, even if you hit another input button. In the PUNCH mode, hitting another input button will automatically turn off any input previously turned on. With Flash in the LATCH mode, the MUTE button mutes the audio when pressed, then un-mutes it when pressed again. In the PUNCH mode, the output is muted only while the MUTE button is depressed. Switching from LATCH and PUNCH modes is done with one of several DIP switches on the back panel.
So, you can switch audio inputs and mute things in some pretty fancy ways, but this is hardly all that Flash can do. Remember that the unit uses "passive" circuits. Yet another characteristic of a passive mixer is that signal flow can go either way. What we've been referring to as inputs and outputs on the back panel are actually bi-directional jacks labeled GROUP A (four stereo pairs) and GROUP B (one stereo pair). You can input a signal into GROUP B (normally the mixed output) and send the signal to the four pairs of jacks that are GROUP A. All of a sudden you have a distribution amp of sorts. You can send a voice track to the left side of GROUP B and send four signals to four different effects boxes using the four left channels of GROUP A. Taking this bi-directional aspect of Flash a step further, you can take the four outputs of these four effects boxes, send them as inputs to the right channel jacks of GROUP A and output them as a mix on the right channel jack of GROUP B. Give that one some creative thought.