ARC LS-15, thumbs up or down?

I am considering making the jump to a tube pre. At presant I'm using a Classe DR6/CA400 combo driving Thiel CS5i's. Pre/Pwr ic is MIT med imp 330 shotgun. Speaker cables are MIT 770 cvt twins. My local dealer has let me an LS-15 to demo. I've noticed a vast improvement overall, but now find listening a bit fatiguing. I'm working with the toe in, but haven't totally solved the problem. Also I noticed that the pre has a low level hum coming from the pwr supply. Barely audible with ear against the top. Is this normal? I like the sound. The price is right ($1400)? Would my money be well spent, or should I be going in another direction? Any input from others who have been down this path would be greatly appreciated.
I recently upgraded to LS-15 from a CJpv-10a and have not regreted it a bit. I have not noticed any fatigue at all, but I understand Theil can be picky on what they are matched with. I also have not noticed a humm, but I don't think I have had my ear that close to it yet, will try it later on and let you know. On the plus side $1400 is a good price so if you end up not likeing it you could at least get that much or maybe more back on it, or sell it really quick for a hundred or so less. Also make sure you are running your source throught the "direct" input, it makes a nice improvement all the way around. Good luck, I'll get back to you on the humm, but I don't think it is a big deal.
Thanks for the post No_money. The hum may be normal for the LS-15. The pre was a trade in on a Ref II. I wasn't sure since it's a used pre and I'm not schooled in tubes. I am using the direct in for my source and it does make a difference. Thanks
Mrderrick, I checked out my pre, it has a real low hum also. Must be normal. Happy listening
Have owned ARC pre-amp's and amp's for well over 15 years, the LS15 is a great pre-amp, easy to maintain and easy to use with remote, you should be happy for many years. Price seems right, and if you don't like it you should be able to resell and get your money back. I have found that it sounds best in my system using the Bugle Boy 6DJ8's which can be found on Ebay selling for about $30.00 to $80.00 for the set of 4 (they will be used with many of hours left). Good luck......Bob
You have noticed an improvement so far, therefore, I suspect you will ultimately be happy with your ARC. With my ARC I found the stock Sovtek tubes to be a bit bright and the bass to be OK but not great with my B&W Nautilus 805's and dual Velodyne subwoofers. I replaced the coupling capacitors with Infinicaps which are the caps ARC now uses in their new units. I switched to Seimans NOS tubes and bought a set of tube rings from ARC. The improvement is vast. The highs are extended but non-agressive. The mids and upper-mids are much more open and airy and the bass a tad more powerful and much more detailed. Less fatiguing.
If you aren't a big tweaker and don't want to venture into replacing the capacitors, you may want to try the NOS tubes and tube rings. Big improvement. I also found that with the tube rings that you can do a bit of tuning by adjusting how far up or down the tube you place the rings. The higher up the tube they are placed, the less affect they have.
Enjoy. Woodrow
Thanks everyone, I've decided that it's a "keeper". The pre has been retubed and has the ARC dampening rings. It also has the Infinicaps. The previous owner was very fussy. Just one thing though, it looks like the pre is set up for high 18db gain. When the volume control is all the way down there is still sound. I don't know if this is good or bad? I have the drawing showing the resistor locations. I've also gotten the fatigue back under control. Had to re-toe the speakers.