Next upgrade: cables. But which ones first?

Please help with guidance regarding cable upgrade. I’m a total cable novice. So far I’ve focused on upgrading components and I think the next move should be cables. But where to start?

I have B&W 804S speakers, McIntosh MC275 amp, Lamm LL2D pre, Rotel RCD1072 cd player, a Squeezebox Touch, and I plan on getting a DAC in about a year. I have two 10 AWG dedicated power lines with hospital grade outlets, and the system makes no hiss, no hum. All power cords are stock (none shielded), speaker cables are magnet wire (DIY anti cables), and ICs are Nordost cheapest RCAs.

I’m trying to decide whether to upgrade speaker cables first, or power cords first. While ICs are still cheap, I guess they are a small step above the speaker and power cords. I also realize this is yet another form of source first vs. speakers first debate. Yet I need to decide what would make a larger sonic impact for about $1000. I could buy used in the US or DIY, but I’m overseas so getting a bunch of cables and trying is not an option.

Thank you!
my take on this is to think long range and determine what you want to spend and achieve. all the cables are important and you want to achieve synergy with the system so a mix and match and some here and some there haphazard approach can cost a lot of money. i have never bought any ultra expensive products but have used some moderately priced wireworld and kimber. i now use morrow cables for my ics and spks and ps audio for power. i like to look for bargains and think you can find some real performance enhancing cables without spending a lot of money by looking for sale prices or demos. most people say speakers first which i did with good results. but i do ascribe to the weakest link effects the entire system. good luck and enjoy the search. there are a thousand reviews out there.
Power cords should come first. They serve as the foundation.

Some good advice here:
Please be sure that you hear a difference (that you like) upgrading your cables before you spend lots of money. There is much disagreement about the (practical) value of expensive fact I know many running expensive systems using stock wire and cables because they can't hear the difference. Don't just buy into the hype unless you can hear the difference.....
Point taken: I'm not after trophy names - just better sound. So I'm not really thinking 3 PCs for $1000.
The Nordost guide was a good read. Seems PCs would be a good starting point.

I guess the next question would be: buy a used PC for about $350, or DIY for the same amount?
DIY represents a very good value for power cords. You can customize them to your needs and they are very easy to construct. Dollars spent equate to 3x to 5x equivalent retail value. The only downside is unproven resale value. If you go the DIY route you also might consider upgrading or even eliminating the IEC inlets on your equipment.

I'm not sure I agree with power cords being the bedrock of a system. Their effect is very variable and totally system dependent. It's also my experience that you have to have the rest of your system in order before you can hear the effects of power cords upgrade. It's a chicken and egg problem.
Power cords may not be the bedrock but I always found that in my system every upgrade was worth it.
I would first try a good power cord with LAMM pre-amp. And I would start with Purist Audio or Custom Power Cord Co. Not with their entry-level models and not shorter than 5ft.
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I'm no expert on power cords, but I have recently come to the conclusion that there are better than entry level power cords. DIY is an excellent path for pursuing value in better quality power cords. On a dollar per dollar basis the component quality in DIY far exceeds equivalent commercial products. You simply don't see Furutech or Oyaide connectors on $100 power cords.
my two cents is that i would buy an inexpensive power cord to try on each of your components and a set of interconnects to see if you're interested in changing your sound.

i've had blue heavens and red dawns in my systems and i never felt they let the other gear work at 100%. if your speaker cables work as well as anti cables, you're good to go with them unless you're itching to just experiment, i've got a set of them and they punch well above their price point.

and i agree with the idea that the power cords are the easiest way to jump on the cable wagon - the thing about them (in MY experience) is that a good power cable ALWAYS sounds as good or better than a stock one (sometimes a lot better), while interconnects and speaker cables can just sound different sometimes - not necessarily better or worse. and i really don't want to start an argument here, so please, please no one hijack this thread to start this debate again, but one thing i've had to watch out for in my experience is that you can't judge some cables right away (particularly power cables), they often do have to run in for a few days to sound right.

if i had your system and i was playing around, i'd buy a power cable from one of the adiogon guys (my audio cables, element, cullen, etc.) or find a big, fat, shielded ps audio cable for $100 or so and then buy some interconnects in whatever price point that you want to experiment with.

any mit or analysis plus or most of the van den hul interconnects (disclosure: some people get a hum when they use a vdh first or second interconnect with tubes, as they are carbon, not metal), for example, would sound better than the nordosts, i would think.

but it's all up to the audio gods in the end....
good luck!
Inna- power cord- "not shorter than 5ft."

I read it here somewhere that generally it is not recommended. I myself did not compare, all my power cords are 5ft. I think, the idea was that shorter cords don't have enough "time" to filter the current. Probably depends on particular cords and applications.
Great feed back. Thanks to all!

I'm leaning towards power cords to get started. For the time being it will be one power cord, actually. I can go for a $350 PC. So I could buy 2 Oyaide connectors and still have about $150 for 3 to 5 feet of conductors/shielding/etc, or could buy a used cable.

Several Lamm preamp and Mc amp owners I've gotten in touch with have had very good results with Purist power cords, but they were using really expensive ones, like Dominus, which is 10 AWG and well beyond my budget. Looking at used Purist PCs closer to my budget, like Venustas, I see they are only 14 AWG...which kind of leads me to wonder if their entry level is good for these applications. Thoughts?

Keep it coming!
i personally have never been impressed by a 14 awg cable on an amp, but maybe the venusta is special, i know people love that brand.

the cables i've ended up liking on amps are all 10 and lower. my favorite one i have for amps is a 10 awg solid silver, crazy power delivery.
You may want to get Custom Power Cord Top Gun 4ft. new that is now here at the auction first. It is not going to be expensive and it is a great cable though quite stiff. I use it myself with both my cd player and integrated amplifier. Purist Proteaus, Dominus and some newer ones should be better but more or much more expensive. Let your LAMM get acquainted with this cable, it might like it.