Help with first cable upgrade.

I have a Musical Fidelity v-150, rotel rp-3000 turntable and an old Sony CD player.  I have 2 sets of speakers B&W CM2's and JM Lab chorus floorstanding speakers I may have to part with due to space.  My power cables and interconnect cables are cheap stock.  My speaker cables are a 20 year old or so set of MIT shotgun cables.  Any recommendations for budget friendly cables that may help the bass or soften the brightness of my system?  Thanks.
I want to follow up after trying some new cables that were provided by a fellow poster.

I replaced a pair of stock interconnects with Blue Jean LC-1's and a stock power cable with a Cobalt Cable power cord.

After much swapping of cables, there was a noticable difference with almost all of my digital music.  While subtle, there was definitely (to my ears) a less sharp edge to some tracks that I found a little painful with the stock cables.

The most noticable difference, however, was found by accident.  I was turning up the volume on a disc (with the stock power cord) but had yet to hit play so I was only hearing (what I assume is the electrical signal/hiss/distortion whatever.)  I decided to do the same thing with the new cord and there is definitely less noise at the same volume level.  I don't know technically what I'm no longer hearing at the same degree but I have to assume that this translates in the music as well?  I will be replacing all of my power cords and interconnects in the near future as I'm a believer that an improvement can be had without a fortune being spent.  Thanks to all for your recommendations and sharing your personal experiences.
I’m a big fan of power cords so that’s a valid choice.  Quickest bang for the buck is still the Loki for sure. Power cords are fun but it’s hard to find good ones for the price of a Loki. Ice Age is the only company I can think of whose best cables are in that range. Most other companies price their really good cables in higher price tiers. Do think about upgrading to a transport or streamer that can use an external DAC like others have said. That’s when the fun starts.
Thanks mward.  I'm shopping for the transport now as well as an old CEC CDP 3300 for a second system.  I'm sure I'll end up with the Loki but I do believe the cable upgrade has made enough of an improvement to be worth the expense of even a minimal upgrade over stock cables.  Thanks again.
I would give Audience Ohno interconnects and Audience Forte F3 power cord a try. I’ve used these in my system and liked them a lot. The Ohno bested the BlueJeans ICs and the Forte F3 power cord was a significant improvement over stock power cord on the amp and DAC. See if CableCo has a special on these. 
Hey thanks audphile1.
Things have changed slightly since my last post.  I just picked up a Musical Fidelity A3 24-Bit CD Player for $150 in near perfect condition.  I put this in the system last night along with a PS Audio upc 200 and there's quite a difference.  Now, the mid-range seems a little heavy almost drowning out some of the highs, although the clarity of each instrument is much more detailed in a good way.  I removed the Blue Jean cables and replaced them with some Tributaries Silver interconnects that came with the components and that solved the mid-range issue but the highs are a little bright.  Included with my purchase was another pair of cables the Wireworld Equinox lll which I'm going to try later today.  It appears I'm looking for something that falls in the middle of the Blue Jean cables and the Tributaries.
I moved the Blue Jean cables over to a really cheap Onkyo amp with the Toshiba CD player and those seem to be a perfect match running through a pair of JM Lab chorus speakers.

How much if any improvement is there in using XLR cables as opposed to RCA?  Just curious.