Single-wire spades from amp to biwire spkr posts?

If you like your Cardas cables, before buying anything else, you should try a high quality (like Cardas) set of jumpers on the speakers. Run the speaker cables to the MF/HF posts on your speakers, and then jump to the LF posts(or try it both ways and do what sounds best). Instead of stacking the spades, you might try finding jumpers with spades on one end and bananas on the other. That way you can attach the bananas to the posts with the main (spade terminated) speaker wires. If your jumpers have spades on both ends, try some Cardas bananas connected to the spade on one end of the jumpers and plugged into the post with the spade termination. BTW, if you decide to purchase something, there are many internally (and externally) bi-wired cables that terminate with a single set of spades at the amp end (as others have said above). Do a search under cables - speaker, here on Audiogon.

Another option would be for you to construct your own jumpers. It is easy to make a set of jumpers that should perform just fine, and since the length is generally a foot or less, the effect of that wire IMO is about nil, assuming the wire you use is of sufficient gauge (12-14 awg should be fine for the short run) and at least as good as the internal hook-up wire inside the speaker. You can order single crystal copper hook-up wire from Partsconnexion, VH Audio or others, or even actual speaker cable by the foot, and make up your own high quality set of jumpers using spades at one end and bananas at the other. If you are not comfortable with soldering, there are several really good spade and banana models that have compression terminations using set screws. I have Furutech spades with compression terminations, and I believe the highly rated Bocchino Audio connectors also use that method of termination (see the CRL website). If you are using copper wire, some cover the connection using Q-dope, silicon, or other compounds to resist exposure to air and potential corrosion. Many would think using high quality heat shrink over the connected part of the spade should be fine. You will need 4 spades, 4 bananas, 4 feet of wire or cable, and some heat shrink.

Good luck with your trial. If you like the sound but do not like stacking spades, I would bet Cardas would be happy to reterminate one end of your jumpers with bananas.

There are multiple factors, such as how the crossover boards are implemented within the speaker, how the bi-wire cables are set up, and others. Some internally bi-wired cables simply split the number of wires between LF and MF/HF, while others double the wires inside of their bi-wired cables, like with my Purist Venustas. Other manufacturers offer double bi-wire cables that have two separate runs terminated together at the amp end, and some do that while using different gauge wires for LF than for MF/HF. For more info, you might look here:http://www.geocities.com/jonrisch/biwiring.htm

Sthomas12321, the article I referenced above may help answer your questions.