i guess the reason why some older/cheaper gear uses 1000-2200uF PSU filter caps is because of physical size and cost of historically available caps. pic related uses 50V 4700uF that are pretty thicc. if i'm going to shop for capacitors in 2025 i think it's safe to say i can upgrade to at least 4700uF as in >>2922728 >>2922731.

the voltage rating should be at least 35V to be comfortably within spec of the original designs. polymer electrolytics don't seem easily available at 4700uF but i could maybe use 1000uF polymer in parallel. or for example there is nippon KMH rated for 105C temperature, 100V 4700uF with 35x50mm case size.

https://chemi-con.com/wp-content/uploads/2021/05/KMH-Series.pdf

or for example there is nichicon FW which claims to be suitable for audio use, rated for 85C temperature, 35V 4700uF 18x35.5mm case size

https://www.nichicon.co.jp/english/products/pdf/e-fw.pdf

the nippon KMH seem fine as long as they will physically fit but are there other things to look for and maybe 6800-10000uF would still work