Hello JLM
Belated welcome (your thread probably came in during a busy time and got buried).
I've been running near-field (in-room) for 10+ years. Looks like you have a good sized desk facing near a wall. Like your collection of small amps. Have you ever considered headphones?
I might need to save the headphones for when I'm travelling, 'the wife' has a hard enough time talking to me already

Have you considered active monitors? (Your old A2+ are powered speakers, that's different.) Active speakers use one channel of amplification per driver and a low voltage crossover upstream of the amps. The advantages of active design are huge: cheaper/smaller, more coherent (you don't hear separate woofer/tweeter), more dynamic, very flat frequency response, and unbelievably deep/full bass. The recording/mixing professionals use them in very similar settings. But for their work they need a very analytical/dry/revealing presentation that most would not find enjoyable for home entertainment. But home versions are out there. Audiostream.com and soundonsound.com are good places to start looking.
With active speakers you need only a source (computer with DAC), and a volume control (some actives have a volume control on the front so even that can be eliminated). In fact, there are a few active speakers that include a DAC (but as fast as DAC technology is changing I wouldn't go that far). How's the Schiit preamp working for you? I looked into them but determined that they're really primarily designed for headphone use. But I'd highly recommend a Bi-Frost multi-bit for a reasonably priced system running single-ended (RCA) interconnects.
I like the Schiit Vali 2 preamp, it is OK for the money. I think you are right in thinking that it is aimed for headphone use. I tried using it as a 'master volume control (DAC at full volume, and tube amp at full volume), with the Schiit Vali2 inbetween the DAC & tube amp, and in that respect it worked well. I removed the Schiit Vali 2 preamp from my system as I didn't like the 'crackle & pop' sounds, when it switched on (there doesn't seem to be any 'soft start' or auto muting of the output on start up, and these noises worried me enough to remove it). It is fairy well made, so I might have a use for it with some different tubes (I've seen a lot of recommendation for Philips tubes that work well); I will make a decision after I upgrade my DAC to an ESS Sabre 9018 type. I'm trying to go for the clean analytical sound on my source, as I have the sub & tube amps to warm & balance things out (well that is the plan i have in my head).
Yes, I started looking for a pair of Genelec speakers (recording studio type of active speaker with some really nice isopods included), the smallest I considered for desktop were the Genelec 8010A - link
http://www.genelec.com/studio-monitors/8000-series-studio-monitors/8010a-studio-monitorbut settled on the cheaper A2+ (home user market) as a starter (nice powered small speakers with the DAC built in). Looking back, the Genelecs were twice the price of the A2+, but I wish I had bought them. I quickly grew out of the A2+ and was lucky to find a pair of Bowers & Wilkins XT2 passive speakers at a massive discount, which was a significant step up foe me:

At that point I had a big smile on my face every time I re-listened to my music collection. I was lucky again that a friend of mine recommended looking to REL Acoustics for a bass system (I almost fell off my chair when I saw their prices

), apparently they make some of the best subs and have a unique feature which is their 'Higher Level Connection: From the REL a Neutrik Speakon connection that connects to your speaker's or amp's existing speaker terminals (so they piggy back off the existing main speakers, hence the closely bound cable at one end to support the heavy weight of the cables).

I have adjusted the crossover point so that the 'bass' appears to be coming from the B&W XT2 speakers, and I am presently surprised at how 'musical' it is with the crossover set to about 85Hz.
Hey Carlos,
I run a little desktop rig myself. I hate to admit it, but this 'secondary' system gets more use than my main rig.

Gratz' on the T-Zero. That's a wickedly good lil' sub.
Hi Zero, yeah the REL has been the biggest upgrade (it made the biggest difference to sound), I think the reason the sub is so good is that REL Acoustics only make subs and nothing else. I believe they are made in Wales. This little sub punches way above its weight, I think I'd have to spend a considerable amount more to get any improvement. It is refined, but very good bang for buck, and really suited to people that don't have a dedicated 'sub out'.
It is almost like the REL was built for my setup, it is recommended that it should be behind the main speakers positioned a few inches away from the walls, in the corner, which by chance is exactly the space I have. I would really recommend getting an audition of a REL sub if you get a chance (I was 'lucky' again to get one a a huge discount), the higher level connection blends seamlessly and really adds emphasis & clarity to the mid and high end sounds (it is funny how the mind works)
Did you have power aberrations? I find they are very localized and personally have never had a need for AC regeneration/etc. And other than tidying up, why are you bundling your cables together? Most worry about EMI/RF leakage/shielding issues between cabling if close by and especially if they are paralleling.
I had trouble with strange noises, when certain LED lights, dimmer switches etc.. were used, so thought it best to isolate the power supply to my audio equipment. It worked out fine and since have not had any problems. The AG500 AC regenerator was about £250 so it is pretty reasonable for what it does.
Yes the bundling was due to the cables being so heavy, the photo above were just the temporary bindings so that I could work with the larger gauge wires; I have since tested the cables work & have just added aluminium foil and copper braid to fix any shielding issues at the 'main' binding point. THANKS for the reminder about "bundling your cables together", I probably might have 'forgotten' to do the extra hours worth of shield.

The Van damme black series UPOFC cable is seriously heavy, and in reality only needs to behave like a interconnect because of the 'higher level' connection, but better to over do it and shield anyway.
btw. JLM & Zero, THANKS for all the advice, your help is very much appreciated, and it's what makes this forum such a good place.
I hope this thread is useful as an example of how I've started with nothing, and built up my system little by little. I'm sure that there might be 'better' setups, but this is what I have based on my budget & my luck in finding good deals that get me 80% of the way to a reasonable desktop system.