$1600. preamp

for $1600. would you buy a manley shrimp?  why not? what else then?
No I would not. $1600 is overpriced for that . It was about $1800 new. You should take a look at the Quicksilver linestage preamps. The remote 6DJ8 is $1595,and the non remote 12AT7 is $995. I have owned both and they are a true bargain!
i owned a quicksilver pre. i didn't think much of it. i would definitely consider the amps though.
Spend around $1,000 and look for a ModWright SWL 9.0 SE or spend a little more than your budget for the LS100.
I think the Manley would be a great buy, a new one with remote retails for $3800 used $2,000 all day, the Shrimp was a earlier NON remote version so it was less. The circuit design is very simple and it can drive any amp (200ohm output). Also, The sound is amazing!  The ModWright is a great pre amp as well. I have had both in my listening room, the Manley Shrimp is still in my system and the ModWright is in my fathers system. They are both great deals indeed! I owned a Quicksilver pre amp in the 90's, seemed a little cool and dry for a "tube" component IMO. I sold it. 

Matt M
I'd add a few $ to get BAT VK32.
Save some money AND get a wonderful Mapletree Audio preamp right here on Audiogon:

I bought a Manley Shrimp years ago on here for about $900. I had it for about six months and truthfully I didn't think it was anything special. I sold it for about what I paid. Shelling out $1600 now would be a huge overpay.
$1,600 for a Shrimp is too high. The Jumbo Shrimp (version with remote and some other changes inside) would be a good deal at $1,600. i use one in my office system and really like it.
Pass labs X-1..
home demo from Reno Hi Fi..

At this price range, you should put the Audible Illusions Modulus 3A on your audition list. Galen Carol Audio sometimes has factory refurbished units at a nice price.
I owned a Modulus 3A and think it be a great pre at the price for a vinyl based system. Would look for a used Audible Illusions LS1 for digital. Currently using a Jolida Fusion pre ($1350 new) and enjoy it.
Atma Sphere UV-1.   In that price range, you can get one with a phono stage.  It blew away my Quicksilver pre, though I use it with Quickie silver monos.  
The Audio Research SP-14 is a nice pre-amp. It has a good tube phono stage in case you want to come over to the dark side sometime, and can be had for $1000-1200. 
No question about this recommendation, check out Don Sachs’ tube preamp. The preamp is custom-made, based on 6SN7 tubes and is the most satisfying amp I have ever had in my system, which include Modwright, Belles, Berning, and a upgraded HK-CI. It is detailed, transparent and has incredible extension on both the low and high end and a luscious mid-range. Google "Don Sachs" and you can learn more about his wonderful preamp, which is right in your price range. Support the boutique manufacturers, is my recommendation. Whitestix
I can second this.  I've been enjoying this amazing piece of gear for a couple of months now.  This hits WAY above its price point.  Highly musical, yet all the details are there.  Cymbals ring and shimmer, voices are "you are there" (they are here?).  PRAT reminds me of the better NAIM gear, except now add some richness.  I bet Don's amps are amazing as well.

Ayre 5xe mp
I second the Jolida fusion pre. It's got a powerful exiting but smooth sound. iMO. Thinkin about the upgrade but not sure I need to. 
Odyssey Candela is very good for the price.  
I Own a Denon 7.2 receiver. I am using it for a pre.  I have an st100 Rogue amp. What difference would  a nice pre make?
Used DeHavilland Ultraverve. For even less, Van Alstine T8+ or Fet Valve, used Bryston BP20, 25. Have had good experiences with all of these.