The only one I have heard is the Rotel. It would be an OK match with the Paradigms. Be careful as the Paradigms can be very bright, if not harsh with the wrong components. I use to own the Studio 40's and really only liked them when I had tube equipment driving them. Good luck.
The only one of those on your list I've owned is the Parasound P/LD 2000 and it's a fine preamp but one I like better is the McCormack TLC-1. It's a beautifully built piece of gear that completely got out of the way of the music in my system. They can often be found for around $350, a real bargain, and can be upgraded by SMCaudio if you like.
Luminous Audio Axiom preamp <150.00. Best pre for the money. Passive and only one input.
For what he is looking for the Adcom GFP-750 is really quite good - if I recall correctly it was designed by Nelson Pass. It should fit the sonic characteristics you say he is looking for. Good luck.
I will second the Adcom GFP-750. It's a lot of preamp, offering excellent performance for the money (particularly if purchased used). My second choice would be the Marsh.
If we depart from your list, however, you should seriously consider the Bryston BP-25. There is a new listing here on A-gon for a BP-25 priced at $995. I would choose the Bryston before any of the preamps you listed.
Above all, he wants outstanding top-end extension, transparency, outstanding detail, speed, focus, and great bass
I would add, "tonal accuracy". Hardly asking for much, is it:)?
The type of sound described really fits a handful of top-end active pre's. The Adcom may be "on the road" to what is expected -- but, good as it may be, it hardly achieves the targets. At its price point, it really wasn't meant to better, say, a Blowtorch.
Given the requirements, the line level source, and the easy load represented by the Parasound am, my recommend would be a TRANSFORMER volume control. Bent offers these (they also offer a kit, I beleive) at a reasonable price.
The resulting sound should be very close to what you describe. If not, it's due to upstream or downstream elements -- not the trannies.
An idea, anyhow....cheers
For sheer transparency and focus, probably the Adcom GFP-750.
Does your friend have anything against a budget tubed preamp? There are plenty of those on Audiogon. What is his budget? I'm loath to suggest anything without knowing if he's looking to spend $500. $1K, or more, or less. A bit more info would be great, I'd love to help.
The Adcom without a doubt - this is essentially the $4000 Pass Labs Aleph P with a slightly different signal path.
I would throw the Audio Research LS-3 into the mix; a really fine preamp.
I'll vote with Jond for your considering a 'budget' tube pre to go with your Parasound. My only experience with Parasound amps is in hearing their top-of-the-line Halo amps pushed by an SS pre (cannot recall which). To me this combination sounded extremely detailed, had a wide and relatively flat soundstage, plenty airy for an SS amp, yet ultimately the whole thing left me cold. I think it was so analytical and sterile that I longed for warmth and musicality from the rig...something to pull me in more than it did. I've had this experience with other all SS rigs which have impressed me on some levels as this one did. At least give a tube pre a try to see the differences it may make. I might suggest a used Audible Illusions modulus 3a on that front, but there are many others. The combination of a tube pre and an SS amp can often bring out the best of both worlds. I think the sucess of many hybrid integrated designs speak to that end.
Yes, Audio Research LS-3.
Again, The Audio research LS3 will blow all of the above away.
If you can stand a tube preamp, check out the Eastern Electric Minimax upgraded version (about $950 new). Very neutral and detailed, huge bass response. I was going to spend $2k on a preamp until I heard this one-incredible detail and frequency extension. It took about 150 hours to really sound nice, and I swear it is still improving. Really responds well to tube rolling-I couldn't recommend it highly enough. Plus, Bill (the distributor) is a pleasure to work with and provides 1st rate service during and after the sale. For me, the Minimax provides just enough "meat-on-the-bones" with my tube selection that it is real pleasure to listen to jazz and orchestra music.
I have to fully agree with the others about the Audio Research LS-3 or 3B. Fine piece for the price. Does everything very well.
I wouldn't mind getting another for my second system.
Try the Adcom GFP 750. If you like it, a Pass Aleph P or X series preamp will be the next upgrade.
Unless you've already tried a tube preamp now may be a good time to check on out. An Audio Research is what I'd recommend. You may find out you love it. Tube pre's need only tube changes every couple of years, other than that they're turnkey and tubes aren't expensive. If you buy a used one and decide you don't like it you lose little or nothing. If you find you are amazed, like many of us, that you hadn't tried one before then welcome to the club.
Modwright SWL 9, hybrid linestage. $1400. right now, will go up a couple of hundred soon. Sound quality far beyond its price point.
A Parasound pre amp would obviously match perfectly with his Parasound power amp but, the ARC LS3 is the only other piece I would cosider. Go for the LS3.