Which ARC reference component to upgrade?

I have the ARC Reference 3 preamp and Reference 110 amp and am considering an upgrade in the ARC line. I can't do both right now. The question is, which change (Ref 3 to Ref 5SE; Ref 110 to Ref 150) would result in the best improvement in my system?

Ref 3
Ref 110
Wilson Sophia 2
Music Server to Berkeley Alpha Dac 1
Esoteric X01
FMS Nexus cables
I would suggest a power conditioner for all your stuff, except the amp, as the next step 'up'.
I have a Furman REF20i
You might check out that or others..
I recently upgraded my Densen B-250 to the B-250+ and submit, besides changing speakers, I heard the most significant improvements I've ever heard. I'm not talking night and day, but significant. I've read many comments about how the preamp has more impact on the sound than any other component...based on my experience I agree and suggest starting with the preamp.
What is your current system not doing that you would want your upgraded system to do?
Wow, you feel the need to upgrade ARC Reference equipment? You have the "upgradeitis" disease bad, real bad. Seek professional help immediately. :)
I would borrow some Transparent Cables from a local dealer and see if that fits the bill for the next upgrade
I agree with Onhwy61.
What would you like to see improved.
Speakers are usually the best bang for the buck in an upgrade.
Although I am not a fan of Wilson the Sophia's are a decent speaker
Audio Research thrives on customers like this. That's what keeps them in business. I'm not a hater I also own ARC gear.
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Hi, have you tried driving you Ref 110 direct from your Dac , eliminate the line stage. I owned a Ref 110 and found it to be a bit overated. The Ref 110 only sings with easy loads as I think the output transformers are too small and easilly saturate. The result for me was the bass , although it would go deep it was some what slow and loose. Selecting the 4 ohm tap improved matters in the bottom end ,but dynamics then suffered. selecting the the 8 ohm tap restored dynamics at the loss in Bass definition. Please don't get me wrong , the Ref 110 was musical but didn't rock my boat. Your speakers dip below 4 ohms at 220 hz , see Stereophie measurements of your speakers. I believe the Ref 150 improved matters. My amplificatin is now VAC , this gave me what I was looking for as my speaker dip to 3 ohms in the bass. I don't expect you to buy VAC as I did although you could try it for yourself, the Ref 150 could be a good place to start, only my opinion.
How about room threatment? That might be the best advice towards better sound.
I had a Ref 5 and Ref 110 with Wilson Sashas and first upgraded to Ref 40 which was a big step and then from 110 to 150 which was close to the same jump in performance. I'd say in your case the Ref 5se upgrade may be slightly more pronounced since you are going from the Ref 3.
Thanks for the interesting responses. I do have the Furman IT Reference 20 power conditioner and have used it for years after trying a number of others. In response to onhwy61 and Tobb, good question that has gotten me to think more about what the system does well and what it does not do as well. The highs, midrange and midbass are excellent, maybe the best I've heard in my audio room. Bass definition is excellent, but overall bass response is probably the weakest aspect of this system which seems to be similar to Lustformusic's comments. The Sophia 2s are replacing Von Schweikert VR4 SR MkIIs which had a fuller bass response with less definition. And lastly, on "upgrade itis" - no doubt about it. After many years of this hobby, I'm always ready for improvements which get me closer to the music. I'd say that is the fuel which Audiogon runs on.
After many years of this hobby, I'm always ready for improvements which get me closer to the music. I'd say that is the fuel which Audiogon runs on.

Indeed, that is the fuel that Audiogon runs on. Improvements....whether real or imagined. ;)
Get the Ref5se. It is quite a step up from the Ref 3. I have owned all the pieces you mention, 3 and 5, and 5se, and 110 and 150. The 5se will easily show it's benefits into a 110, which is still a great amp. But the 150 can't improve what wasn't there in the first place from the Ref3.