Which Component Needs to be Upgraded First

I owned the ST140 some 15 -20 years ago. I owned the Khorus speakers about 5 years ago. You need a better amp - pure and simple. Updating your source to a better dac would also be a must.

No mention of how much money you have? You can get an awesome DAC today very little money. I think you can do both instead of paying what you might be considering for one.

Get an Oritek Audio modified Zhaolu D2.5 dac for $599 new. It is an absolute giant killer. You can use your Sony for a transport. This DAC is amazing and outperforms dacs cost up to 10X more! You can also sell the Sony and use an Oppo for a transport.

For the amp I would stick with a nice SS or Hybrid amp to control the bass on those X speakers. I own an ART Audio SLA2 that costs only $285 new and it will smoke the once wonderful ST140. This is 200 watts per channel. I can share more if you are interested.

Your speakers can use more midrange and the Monarchy SE160 mono amps would be great for some $1200 or so used. A used Belles Ref 150 ($1400) is also a great amp with better high and bass then the Monarchy. The Monarchy wins out out for mids and wonderful warmth.

Bill

I have found conditioners to degrade sound and limit current/dynamics. I would have to say spend that money on direct 20 amp lines to your room before a line conditioner.
Also get a decent power cord.

I know many differ on opinions of power conditioners, so this is just my experience.

Most interesting. I will check this out. Never seen this before?

They are heavy on the bass as your amp is slow and not controling the woofers in your speaker. A Belles Ref 150 amp will take care of that while the Monarchy amps not as much. The SE160's will control the bass far better then your ST140 however.

I did find a little midrange suckout in the Khorus speaker that the Monarchy amp match well with as the amps have a rich and wonderful midrange.

What is more important to you - better bass control or more midrange presence and treble smoothness. The Belles is also smooth on top and more transparent than the Monarchy. I just think the Monarchy amps have a wonderful tube amp sound without the hassle of numerous large output tubes.

Both amps are great, but your sonic goals are most important.

I have used several BPT power conditioners on my digital front end only with good results. Deeper bass, took out some of what we call digital glare or hardness, smooth highs and improved stage size.

I now use a battery powered CD player so I sold my BPT.

Tvad, I have been reading the site info as well as posts on this unit and I am going to buy one for my house.

Two questions

Has it improved your sound in any way?

Seems this unit will clean ac and surge protect everything electronic in the home. My bedroom TV etc...........

Bill