Buying a sub (Miller & Kriesel) without knowing how difficult getting it to work right would be. This wasn't that big of a cost in absolute terms, but I was a young audiophile and everything seemed expensive, but that it derailed my listening experience.
I should have focused on the mid-treble, imaging and natural tonal balance over trying to get a 20 Hz response.
I should have focused on the mid-treble, imaging and natural tonal balance over trying to get a 20 Hz response.