[Matsablokos]

First of all hello everyone 

 (am new to this forum so forgive me if this is the wrong place to start asking questions)
So, lets get to the point.
My current gear is :
Nad 314 Stereo Integrated Amp
triangle titus TZX
Sennheiser HD 598(driven directly from the amp)
and the source is my pc connected via minijack to RCA cabble 

 (my pc has optical output the amp doesnt have opt input)
 
To be Honest the sound result is crappy 

 am not at all happy with what it sounds like.
Recently i came up with a pile of cash (my budget is around 500euros)  and i was thinking instead of buying a DAC to go for the
Marantz pm6005. The problem is that i live in a crappy city and i can't find one to listen 

 .
So should i buy a new amp (pm6005) or just a DAC?
If i end up buying the AMP does it combo well with my current equipment?(triangle titus TZX, Sennheiser HD 598)
I would love some experts info on my problem.
 
Thank you for your Time and sorry for my english(not my native lang)
 
(forgot to mention : my music is mostly on flac format and my music preferences are currently Stoner Rock and Progressive Rock)

 

[PurpleAngel]

I'm going to guess your using the computer's on-board audio    to send an analog audio signal to the NAD.
So adding something with a better DAC (Digital to analog Converter) feature would improve audio quality.
 
Asus Xonar DX or D1 (used, 60 Euros?) sound card or D2 or D2X (used 100 Euros?) sound card should improve audio quality.
Hifimediy Sabre U2 USB DAC (50 Euros).
E-DAC  USB DAC, made by Epiphany Acoustics (90 GBP).