fdd5d689_e_Notes_on_Coupling_Capacitors__Impressions_HV
[Brand] Aerovox AFPS - Metallized Polypropylene, 200V $3.49 [Impressions LV] These are really nice caps. Solid bass, clear detailed mids and highs, very little grit or grain. Clearly better than the Solens or the stuff from DigiKey, these give the Kimber Kaps a run for their money. In fact, I couldn't tell the two apart (see note in the high voltage review). Won't replace the Jupiters (see below) in my preamp, but I would think they are about as good as a polypropylene caps is going to get without spending a bunch. [Rating] 3 [Impressions HV] 
Ever since writing about how much I liked these, I have received tons of emails asking about them. Having not used them in a while, I got to second guessing myself. Maybe they aren't really as good as I thought. After doing another test, I am happy to say that they really are that good. To put it in perspective, they are clearly not as good as the Auricaps, and after extended listening, not as good as the Kimbers either. But, compared to the Solens, Axons, etc, they are clearly a step up. I still think the Solen with the Vitamin Q bypass is better, the Aerovox having a little less resolution and a little less detail and being a little colder, but only a little. Still a real bargain.
ecp audio diy: Some Notes on Coupling Capacitors
Impressions HV