kalali---For one thing, the tape out jacks are fixed in level, not variable like the mains, so they can’t be used to feed a power amp (unless your amp has level pots). Also, they are taken from before the final stage of amplification in a pre, and their output impedance is often different from that of the mains.
But as cleeds said, those outputs are also used as the source for digital recorders, as well as surround sound processors and digital room correction devices (DSPeaker Anti-Mode, for instance).
For one thing, the tape out jacks are ... taken from before the final stage of amplification in a pre, and their output impedance is often different from that of the main
Not necessarily. On some ARC preamps, for example, the tape out is just a "pass-through."
To point out another obvious one - the tape loop (with monitor switch on/off) is also useful for connecting an EQ in the signal path on any source. Would apply to any effects processing actually. I haven't used them this way in years, but have used them that way with a spectral analyzer with no EQ in the past and it can be at least interesting.
Not suggesting that most people are using tape decks these days, but it still has its utility for some.
I have a question that I'm told pertains to tape in and tape ports: I was advised that I should try to use tone controls in my system and see if I like the results. I have an Adcom pre and was told it could be inserted into my system, and "play" along with my existing Audible Illusions Modulus 3B preamp. As I understand it, the Adcom preamp would only be used for its tone controls and the way to accomplish this is to use its tape out ports.
Is anyone familiar with how to do this, i.e., how do I set the signal path? Is it source to Adcom to AI to amp? Or souce to AI to Adcom to pre?