How would you prioirtize?


I have been following this forum for about a year now and it has definitely helped me improve the sound of my system without much expense.  I now find myself ready to step up and spend some money for the next few steps in my adventure.  I have come up with 4 areas that could help me rise to the next level.  I would like advice on which order you would take these steps.  I have ability to spend $2-$4k every 6-8 months.  
I currently love my system, but I can hear room for improvement.  With the right record, I can turn it up to around 100db and it blows me way.  Other records don't sound so great even at lower volumes.  I know that recordings differ, but the bass gets boomy and the details are lost far too often.  I can't help but feel that with improvements in my system all records would sound much better.  I want to widen that sweet-spot.  BTW I do clean my records, it's not pops, it's the richness, details and bass definition that is off on some recordings over others.

My system so far:
  • Turntable: Thorens TD:150 / original Kugel arm / DL 160 re-tipped by Sound Smith / on springs-maple board-springs.
  • Power: McIntosh MA 8900 / original power cable / orange fuse (it does make a difference)
  • Cable: Blue Jean 12
  • Speakers: Belle Klipsch / ALK Extreme Slope crossovers / Dynamat dampened / on Hardwood sprung floors away from side and back walls / toed-in.  My system has been build around these 70's era speakers.  I am emotionally attached to them, they have a great story.
  • Room:  25' x17' open space and lively / slanted ceilings / 3 windows on one long side / carpets and curtains.  Listening couch is 9' way from speakers, somewhat mid-room.
Below are the items on my list of improvements in no particular order:

  1. Source: a. Replace the arm on the current TT (AMG 9W2 is an easy swap I am told).  b. Replace the whole rig.  I have always wanted to have a Thorens TD-125 and I am in contact with Dave from Vinyl Nirvana.  Besides being the same vintage to my speakers it has a more easily swappable arm-board.  Arms on my list include Audiomod, Origin Live, Groovemaster, SME, Thomas Schick and a few others.  IMPORTANT:  I got ahead of myself and purchased a Sound Smith Zephyr MMIC that I would like to use on the next arm.  It was too good to pass up...
  2. Phono Pre:  I am most interested in Decware and Herron.  Decware would need a Step-up transformer for the Zephyr MMIC
  3. Isolation:  Solidsteel wall shelf for the TT.  Townsend speaker bars for the 18" x 29" base (I don't think they make podiums that big).  I was originally going to put them on Pavers, but I feel that I should go big after hearing reviews on the Townsend ability to isolate. (buy once buy well)
  4. Cables and other items:  Power cords, better speaker cable, other isolation, room treatment.
Thank you for your time and helping me wade through his information.

Eddie
128x128edgyhassle
Thank you all, I appreciate the input.
@nekoaudio yes, I only do loud on occasion just to see how far I can go without noticeable distortion.  Mostly much much lower. Do you have treatments that you like? GIK etc or other. It's a tough room due to odd angles etc.

@erik_squires  Same question to you.  Not expecting either of you to solve my room acoustics just a way to begin and tips.  

@vinylzone  I guess I feel my weakest link is the tonearm so your source idea rings true.   For this sweet sounding entry level turntable this creates the problem of options.  Currently good sound, few options for upgrade. 

@millercarbon I appreciate all of your considerate thoughts.  I will definitely PM you as I have more questions.  I have already learned much from your advice to others.  
What is the floor construction? Foundation level or upper level/suspended plywood? If you jump up and down do things vibrate/shake rattle or move? If so isolating speakers from the floor with isolation pads like Auralex Subdude or similar might be first thing to get a handle on to control the bass and avoid obscuring midrange accordingly.

In general you want to understand what makes your room tick before attempting any major changes.

If you clap your hands do you hear an echo?  High ceilings and large rooms can be particularly challenging to tame if needed. 
In the corners behind the speakers, go floor to ceiling with GIK Soffit Traps. ($1K)
Add curtains and a rug if you can/appropriate.

Between the speakers, GIK Impression diffusors/bass traps.

244 Panels at the first reflection points

Note GIK is running about 8 weeks from order to delivery right now.

You can save some money by using ATS panels instead of GIK, but you should still consider their soffit traps as your first purchase.

Expect this to change your tonal balance somewhat.  :)
@edgyhassle for improving the bass, I'd recommend thick corner/bass traps. The brand doesn't really matter, as long as it is thick and actual absorption (with data to back it up, like GIK ). There are a lot of products out there that are advertised as acoustic treatment or acoustic panels that won't really do anything for bass.

It's also very possible your room is hurting the clarity and detail that your setup could produce. Echoey rooms are notorious for making it harder to understand voices, and of course that applies to other sounds as well. In addition to acoustic treatments, just regular furniture and filling the room with stuff can really help with that. Adding heavy drapes over the windows is better than nothing.
@mapman Yes sprung floor, plywood hardwood planks between suspended beams.  Prior to adding the springs you needed to be careful on how you approached the TT for it not to bounce. I would tiptoe.  Now it is good unless I jump.  No echo clap, learned this one from my friends at Meyer Sound in Berkeley.  Furnishings, carpet , curtains and shelves of records seem to help control the sound.  The walls do need help.  I definitely need to isolate the speakers, thanks.
@erik_squires  Thanks Erik, thankfully I can adjust attenuation for tweeter and squawker with the ALK crossover, makes it easy for any room treatment changes and absorption.  I have played around and gotten creative with treatment using cloth screens to see if it makes a difference...it does.  More fun ahead.