Are upgraded power cables for subwoofers worth it?

If one believes power cables make a difference with the rest of their equipment why would they not believe they could make a difference with subs? PC's also affect dynamics both macro and micro. So, per everything in audio, believe what you want to believe, but don't you think it may be worth your time to at least test the hypothesis prior to making assumptions.

@hilde45 I'm well acquainted with placebo effect, been around the block a time or two over the decades. PC's affect dynamics and specifically how those dynamics delivered. Specifically as to how they affect subs is damping factor, some cables can accentuate resonance, others may be too damped down, transients another factor. I now make my own PC's based on designs of @williewonka , these with various AWG and wire, these specific recipes for my REL subs which hit the exact sweet spot between the overly resonant and damped. Now this allied with dedicated 20amp, 10AWG circuits for amp/subs, proper placement of at least 2 subs, proper crossover settings and volume on subs,  and high level REL connectors (my own recipes). I've long had issues with integrating subs, mostly with low level connections, even with dsp. With the REL's and all my optimizations I finally have the amazing coherence I've long sought, if one is extremely sensitive to subs and coherence PC's can be a critical aspect in getting this correct. How one can conclude PC don't affect dynamics which I could also define as current delivery, just as it does with pre's, amps, sources is illogical to my way of thinking. I suppose some just aren't as sensitive to these things as others.

Upon further reflection, I've been speaking specifically to my recent experience with the REL subs. In consideration many subs use class D amplification I'll agree they less sensitive to PC vs at least some REL's. Class D much more efficient, switching power supplies makes them less sensitive, yet I still heard slight differences with my class D subs, low level IC's made a larger difference here.

REL's implementing class A/B amps are another animal altogether, this same topology used in amps for main speakers, pc's make great difference with these amps. Now with subs dealing with much narrower range of frequencies,  voicing isn't the main issue, dynamics and transients remain. @billstevenson post correlates with my own experience with REL's.

I have three dedicated line, all are 10AWG wiring from same phase on 20amp breakers to AC outlets, never want any possibility of current limitations on any of the dedicated outlets. Power conditioner with any number of components connected on one circuit may draw much current. Amp/subs on their own dedicated circuit, no power conditioning, amps, subs on same circuit so no chance for ground loops. I've tried many power conditioners with any number of amps via lending library at Cablecompany, every one of them impacted transients to some degree, even with outlets dedicated for amps, while these may bypass some of the pathway of other outlets, they still pass through who knows what. Its my experience amps/subs like direct connection to breakers, I can just imagine 10AWG direct wired  no power cords, fuse, IEC, AC outlets.

@jrareform Perhaps I wasn't clear in that I was only commenting on amps/subs on power conditioners. Vast majority of equipment in my system running through BPT 3.5 Signature with film cap and AC outlet modifications (Oyaide R1). In my demos of amps on PC's, the Audience Adept proved best, still negatively impacted transients.

!0AWG is difficult to work with, generally the largest gauge that will fit most breakers and AC outlets, and for longer runs they certainly help with supplying needed current for those transients. For me, the easy part of PC for subs is determining gauge, 12AWG in wall, at least 12AWG PC, and so on. As I previously mentioned I've long heard differences in bass delivery to audio equipment, in other words resonant vs more damped down/tightened bass. First time I really noticed this was with an extremely expensive Elrod PC on some Cary monoblocks I was running at the time, I was amazed by how both the quantity and quality of bass was so different from the other cables I had tried up to that point. Ever since then I've been extremely sensitive to how bass quality is affected by PC's. I absolutely require a deep hard hitting bass devoid of even a wiff of the dreaded one note bass, bass should be tuneful and articulate in my book.

Now I will concede that in my system and some others the main speakers may be delivering vast majority of bass frequencies. With my Klipschorns, including modified crossovers and all drivers, careful placement in corners, modified top plates for max seal I get in room frequency response down to aprox. 32hz at my listening position, REL's crossed over at this freq, and this with only one of the hot wires connected to my monoblock amps, volume knob only two or three notches from minimum. So, essentially the REL's are supplying very little bass in my setup, vast majority of benefit I get is with sound staging, In any case, I simply want the sub to be an extension of the main speakers, coherence is paramount, and this important even with the little bass REL's adding to my system. So for max coherence I posit PC's  on subs should replicate those used on amps, and even preamps, gauges may vary, topology and metallurgy should match. On the other hand, I can envision a situation in which this may not be optimal, perhaps some systems may require a different recipe for amp/pre vs sub.

@jrareform Indeed, you may find relatively unknown cables to be real value, or perhaps not. The diy recipe I use today replaced much more expensive cables from well known manufacturers, depending on materials and length these cable cost between aprox. $350-$700. For anyone interested in diy these are Double Helix @williewonka design, many threads on Audiogon.

Yep, purity of metal is important consideration. This diy design can use any type of wire, I've been most happy with twisted runs of VHAudio AirLock sold core OCC copper, this for hot wire, number of runs depend on use, three runs of 18AWG of this equalis 13AWG, neutral I run either same VH Audio or sometimes litz copper OCC, same variety of runs to get to gauge I'm seeking, 10 or 12AWG solid core copper for ground. After trying many AC connectors, some very expensive such as Furutech NCF50 I've found good value/performance with the PartsConnexion Connex, carbon fiber Rhodium connectors. In fact I've gone exclusively to Rhodium on virtually all connectors in my system. Rhodium no maintenance, no oxidation and once over agonizingly long break in most wide open as in both transparency and dynamics, damn things just flow current, voicing comes the wire, equipment tubes, isolation, room, etc. Building of these most difficult issue, reverse twisting of both ground and neutral wire then interweaving them time consuming and requires much patience. The twist is made via placing long fiberglass pole of proper outside diameter in drill, attach wire to pole via tape, reverse drill, wire wraps around pole. Do the same with neutral or multiple neutrals, then you must spread twisted ground so that you can interweave by hand the twisted neutral, Hot wire rides inside twisted ground and neutral, easy part. The reverse twist is what most believe to be special about this design, add in nearly unlimited choices in wire, hook up wire generally used by most. People use this design for interconnects as well, I haven't.  I used to run some over $5k (accounting for inflation, probably more like $7.5K today) AC cables, generally I ran Shunyata, Purist Audio, Synergistic higher or best models, not saying these weren't nice, but the Double Helix simply flow, sound more like no AC cable than the off the shelf. And those I chose to purchase were the best of what I demoed over the decades.

And not just for subs, I now use them on every single important piece of equipment. Nice thing is you can build exactly to the need which may be unique for every piece of equipment, need more bass for instance, more AWG, voicing, AWG, solid or litz core, mix or match ltitz and solid core for hot and neutral, and then so many wires/metallurgy and dialectecs to choose from, threads here will give you an idea of all the varieties people use.