Where did you sink the most cash into?


I'm not interested in how much anyone  spent, but I'm curious what the single most costly item in your system is- ie, amplifier, CD player, etc.

I will go first- in my present set up, it's speakers. 

But I can't live without my ancient Zerostat (the red one) which was probably 1/3 if what they retail for now. My most enduring audio purchase!  
128x128zavato
Preamp.... It's the most important component in  my opinion..  My speakers ,amp , and DAC were a little less and were about the same price each.  

Of course speakers are the most important but there are a lot of great ones out there.  Upgrading my preamp made such an improvement that I put off buying new speakers in favor of a new DAC.    I ultimately upgradedecided my speakers but honestly don't think I would have benefitted as much if I didn't upgrade the preamp first .
The most expensive piece I own is my pre-amp.  Most expensive new or used (as I bought it).  My speakers are DIY bought used, but given the cost and relative rarity of the drivers, they would be the most expensive piece to replace if I had to build them from scratch. 

Speakers-Amp- Pre-Turntable/tonearm-Cables-Streaming source/DAC-Power Conditioner-Tweeks-Stand, in descending order.

 With the condition that CDs and LPs come a long way first, but much less painfully as they were acquired over 30 years.