I have a pair of ASBA Caroline pedal mated up to a pair of 26" bass drums. I moved from a Speed King to a Ghost, to one Caroline and then a second one for the double bass. I purchased them in the early 80's, several months apart, and they have different finishes on them. Back then these pedals were 'king of the hill' to me due in part to the many features the pedals had over others that were available at the time.
* First of which was the adjustability. I liked that you could do a quick adjustment of the beater angle, although this is kind of a set it - forget it thing. Unfortunately, you cannot adjust the footboard independently of the beater angle, which is a pretty common option for pedals these days.
* I liked that the attachment clamp adjustment thumbscrews were placed above the pedal not at the base/hoop area - that seemed to be a big deal in those days to me.
* It has a couple of impressive carpet spikes to help prevent bass drum creep, which was innovative and useful for larger drum IMO.
* The spring tension could be adjusted very easily, especially compared to the SK & Ghost that I owned.
* The spring could be replaced or removed easily (especially compared to the pedals I mentioned).
* The base rods were stable and easy to insert/remove. With the easy to removal spring and base attachment, the pedal could be folded flat for transportation.
* The wider strap material is robust. Although I've heard of people breaking them I haven’t, and they are quite old now.
* The beater accommodated 26" bass drum diameters nicely without being off-center. I especially liked that the beater rod was a bit thicker than others, which adds a bit of mass and little extra 'boom' IMO.
* I love that it is a long board too.
The Caroline had a couple of features that other manufactures picked up on and made improvements on and are now quite common.
* One was the spring attachment; many modern pedals have something similar but with improvements. A Caroline's weakness was the attachment ring which flattens out/wears out/thins out due to friction. Some manufactures got around this issue by placing a seal ball bearing in this area. The spring tensioner is a bit janky as well IMO, and just look at the Tama & Pearl variants to see a much better design.
* Another innovation was in the area of the strap attachment saddle (as I like to call it), it is essentially a cam that other manufacturers have adopted on their upper-end lines. Now, the Caroline ‘saddle’ is a bit more concentric in comparison to todays eccentric cams, but it is there, nonetheless. It to me is the real ‘secret weapon’ and why the Caroline pedal was so popular.
The real downside to these pedals is that they are no longer made – parts are hard to come by. When they discontinued this pedal, I bought out some spare parts from a couple local retailers just to ensure plenty of back-up. Another more important downside is there are better pedals out there today that have overcome the issues of the Caroline. On the upside, ASBA has been revived, but I didn’t get any answer back from them when I asked if they were going to reproduce the pedal (Don’t know if it’s true but I heard Ludwig had long ago bought the rights to the pedal but it looks like they didn’t really do anything with it – so I don’t know how true that is).
I get the idea of vintage, but I would look seriously at a modern pedal versus a vintage Caroline. Heck the new Ludwig Speed Flyer, for example, is a great choice. In a Ludwig NAMM 2020 video they demo’ed the pedal and I was impressed with how one push allowed the pedal to rock back-and-forth so many times (required very little energy), and certainly far, far greater than the Caroline is capable of. Lastly and so many of the upper end pedals from essentially all manufacturers have much better adjustability/playability compared to the Caroline, with parts availability to boot.
