How do you protect metallic paint without ruining the effect?

I used metallic acrylic paints-the kind for painting miniatures (citadel, games workshop, etc.) to paint a guitar effects pedal.





I want to protect the paint job as it is very thin coats applied with a dry brush technique, but standard spray acrylic clear (Krylon crystal clear) makes the metal effects look like glitter and kills the effect. What can I use to protect the paint without ruining the metal look?How do you protect metallic paint without ruining the effect?
You could try using a ( matt finish ) clear coat. It might work. It protects and and yet keeps the sheen down to a dull finish.