What is the purpose of

Hi. I am fairly new to Audiogon and if this question has been discussed before, I apologize. Reading this you will realize I know practically nothing about electronics, and even less about component design. When you look inside a piece of equipment, you usually see very thin wires used, to say nothing about the fuses commonly seen, with a wire about the width of a hair. Then, when the signal finally reaches the speakers, there is usually more very thin wire throughout the crossover. So what is the point of buying (sometimes) obscenely expensive interconnects and speaker cable? Isn't the audio signal chain only as strong as its weakest link? Or am I missing something obvious? Any answers or comments would be greatly appreciated. Thanks.
The point of buying obscenely expensive speaker cable and interconnects is keep the cable manufacturers in the lifestyle to which they have become accustomed and to annoy your wife.
Your analogy is completely logical and TRUE. However, any steps taken to improve the system will benefit the end result. However, those benefits may not be fully manifested until everything has been "worked to death" and the system has been "tweaked whole hog".

Keep in mind that there are many proponents of "small gauge" wire and even remove larger wires to replace them with "hair fine" conductors. Like anything else, you can find people on both sides of the fence. There are even those that sit and walk on top of the fence. Sean
I am one of those "thin" wire people. There are also obscenely expensive IC's and speaker cables that use such thin wire and, of course, more reasonably priced ones. Even though I prefer thinner cable in general (the largest that I use, other than for power cords, is 26 gage in a single run) it is the sound of a cable that should be the issue (not how thick it is).
The primary purpose of large diameter wire, whether it be solid or bundled, is to have a low resistance level and therefore less power loss, especially on long runs.Since amps and spkrs. have short wiring inside, they don't need large wire. Resistance and loss % may be found on wire resistance tables on the net. You will find that for most audio spkr. applications(3meters), 20ga-22ga is within the low loss category for low-medium powered amps. I find small gauge solid core single conductor wire preferable because of its ability to transmit the signal in-phase without noticeable skin effect(treble freq's running at higher speed on the surface, bass running slower in the core). Anything larger than 20ga is subject to skin effect problems due to the depth of the skin effect phenomenon in copper. Less than 20ga., the entire wire is essentially skin effect. There is also little or no capacitance or inductance problems with this type of wire(correctly configured) compared to braided, litz, bundled wire which, in effect, create the very problems that they attempt to solve. Some say bass gets limited with small gauge wire, and I would agree if you go smaller than 26ga. on a typical spkr. run. And don't try to run your 1000 watt amp to clipping thru a 30ga wire run of 100 ft! Small gauge wire can act as a fuse when improperly used. However, the small wire types I mentioned will yield better overall sonic purity in high definition lower power systems and I would definitely try some out. Smaller can be better.
A friend has a Creek amp that Stan Warren looked over. Stan decided the amp really was a fine design and did not need any mods other than he replaced the internal wires with ones of a higher quality that sounded a little better.
Twl, it is sometimes not the gauge that matters, but the geometry of the conductors being used. Goertz speaker cables are very heavy gauge ( range from 7 gauge to 14 gauge ) but will not suffer from "skin effect" since they are ALL "skin".

As to "smaller sounding better", i agree to a certain extent, especially on interconnects. Speaker cables are another matter ( and yes, i have tried this ). You just can't get the bass impact or control from a 20 gauge wire ( let alone the 26 gauge wire ) that you can out of a much heavier gauge. The use of high efficiency speakers that require less voltage / current to operate may make this more of a moot point though. For the record, i did my experimentation with a set of 96 db speakers and i still found "skinny" speaker wires lacking in "oomph".

I will agree that solid core is typically MUCH better, regardless of gauge. If you go back into the Asylum archives, you will find that i was a proponent of solid wire before they were even archiving the forums. Sean
Sean, I agree that in some systems, bass control could suffer to a degree with small wire. I use a very low power amp and very light quick drivers so it is not a problem for me. Simply a matter of current needs and delivery capability. Goertz is a very good wire if you need to go with a larger gauge because of the reasons you stated. In fact their smaller gauges are very good too.
The conductors in the interconnects / speaker cable, regardless of diameter, are more subject to the effects of capacitance, inductance, and noise than the typically separated wires within a metal chassis. Expensive cables are not necessarily ripoffs. Not all equipment is as you've seen. My pre-amp has a signal path of something like 6 inches and the 2 channels never come within 2 inches of each other.