Electronics Repair Questions? Ask an Electronics Technician
There are not many that have a reverb effect on them. Out of the ones I could find, the Pyramid(which is a powered/booster EQ, not line-level), has it:
Here is a Reverb Kit, which is listed as being used in Home, Pro and Car Audio applications:
Unfortunately, they are not really in demand anymore with things like DSP time-correction, BBE sonic maximizers and of course almost all of these features being built into head units.
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