Hi Digger,

I have a simple Technics Turntable setup and have some rudimentary knowledge in this area.

For your brother-in-law's case, the output from the turntable is too low.
Hence a turntable preamp, nowadays, is always required.
Normally, MM cartridges require less preamping than MC cartridges.

For your other question, audiophiles are usually more concerned about upgrading the internal Tonearm wiring than the external interconnects.
Any decent IC should suffice.
The usual rules about keeping ICs as short as possible also applies too.

There is a very steep learning curve for Turntables.

The following Turntable online forum might be of use to you.

http://www.vinylengine.com/turntable_forum/index.php

Good Luck!

Turntable cartridges all vary in the amount of output voltage they generate.  This is really all over the map and the amount of gain required will vary based on this, but a phono preamp is absolutely required.  Many preamps also include a phono stage as a convenience.  

Steve's ZP3 is a stand alone phono preamp and a very good one, but even that may not yield enough gain if the cartridge is classified as low output, often associated with moving coil designs.  Steve sells step up transformers in varying strengths to assist low output moving coil designs so that by the time the signal hits the ZP3 it can be handled effectively.  A moving magnet cartridge most often has enough output voltage so that the ZP3 alone will do its thing.  

Others talked about reverse equalization.  The recording industry uses the RIAA curve to encode signals on vinyl.  RIAA equalization is a specification for the recording and playback of phonograph records, established by the Recording Industry Association of America (RIAA).  I pasted that last sentence straight from Wikipedia.  Phono preamps deal with this.  

If you can find out the make and model of the cartridge in question everyone can jump in with more guideance.  Don't worry about messing with the IC on the Akai table.

For a beginner or someone on a budget there are many excellent moving magnet (MM) cartriges out there.  This often allows you to avoid getting a step up transformer (SUT).  Moving coil (MC) cartridges come in both high output and low output designs.  Most vinyl audiophiles avoid the high output moving coil (HOMC) designs as they feel they don't bring enough detail, but some of these can be run without the SUT.  LOMC carts are the realm of most vinyl junkies and they can cost into the thousands of dollars, and they will require a SUT along with the phono preamp.  

The good news today with tons of new tables hitting the market is that one can get a very usable table and cartridge combined for under $1k.  A phono preamp will also be needed of course.  My TT setup cost me about $1,500 total and it sounds great.  I do have a preamp with a built-in phono front end to drive it.  When I upgrade some day I will have to likely triple that investment to get a real noticable lift.  Vinyl is worth that investment howerver IMO.

I hope that helps and doesn't scare you off.