I friend of mine (a bass player of course !!!!); gave me an un used set of PYRAMID ULTRAFLEX, He told me he had this set for almost 10 years !!!. I´m not familiar with these strings ??? How do they sound ??? Dark ??? metalic ??? Bright ??? ... I have spirocore... I´m going to change them tomorrow... Best, e.c.
According to a post I saw on rockabillybass.com, the strings you have are probably pyramid nylon cores, and didn't seem very popular- Kind-of like substandard Supernils...
moped10: I realize we are 12 years on from your post but in this case....better late than never. Pyramid Ultraflex strings are NOT nylon. They are nickel flat wire wound on a cabled steel core!!!!! It's too bad this kind of mis-information gets posted on here. I used Pyramid Soloflex (woven steel core) many years ago....and found them to be one of the best pizz strings I have ever used.