Dumbleator
Dumble also occasionally makes a tube-buffered external effects loop called a Dumbleator. A few Dumble amps have a Dumbleator circuit built into them, but most do not. Many users insist that a Dumbleator is required to obtain the optimal sound when using effects boxes and pedals. The Dumbleator has separate "Send" and "Receive" circuit for the effects; a gain control, "Bright Switch" and a return level. Dumbleators are even rarer than Dumble amplifiers. The original Dumbleator was mono-in with mono-out, and follow-up Dumbleator II allowed for stereo output instead.
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