Preamp pairing with B&K ST-140

Hello all:
I'm ending my mid-fi ways and entering the hi-fi entry level realm. I was recently blessed with a B&K ST-140 and I'm using it with a Newcastle R-925's pre-amp out. Sounds good, but I'm told if I upgrade the preamp I'll give the Newcastle away. I split time between a pair of Paradigm Studio 40's and Klipsch Forte's. The ST-140 will hang for a lil' while but I foresee replacing it in about a year???
Any input appreciated,
Thanks Guys:
Bringing in a B&K pre would be a good purchase, and more than likely what I may do. A big factor here is I can get one for $150 - $300. I'm from a guitar backround, and I don't even consider SS, even with the latest technological advances. Nothing beats the warmth and growl of tubie, vintage even better. But thats the 6 string world and SS does good for me in the full audio spectrum, selectfully speaking.
I also ran across info on ARC's older SS line, how it dropped out. The ARC's I have heard where part of high end systems and they sounded really good, but a notch below the tube stuff, based on my limited exposure. And yes $800 for a LS-7 seems a bit high, a fair amount of refurbishing went into it; just last week one went for $400 here.
But what I do know is that the B&K ST-140 sounds great and is a keeper for now. One ponders what mods can be made to step it up a hair more, or for the techie, emphasize an area lacking. The nice thing is there isn't a great need to rush a purchase as the Newcastle pre feeds her well. This duo, I find pushes the Forte's to a liking more so than the Studio 40's I have. Go figure, this anti-phile system I have is quite pleasing. It may be that I'll need quite a preamp upgrade to realize a difference.

Thanks all for the feedback, I'll post results.

Let's agree to say people have different preferences and because one person prefers one type of gear doesn't mean that person has bad taste or the other person has good taste.

For instance, I'm not a big fan of planars or electrostatic speakers. I think they are cool as hell looking but just could never get into the fact that they have such a small sweet spot compared to many other monitor speakers I have had. That doesn't mean I have bad taste and the person who loves Maggies has good taste, it just means my preference is not towards flat panel speakers.

With tube gear, I like the classic tube sound that is very sweet and euphonic. It may not have been the most accurate or transparent, but to me it's very musical. So I prefer musicality over transparency, which also means I don't have bad taste, its just my preference...

The Music Ref. RM5 mkII preamp was a Stereophile Class B Recommended Component so there were several people other than myself who thought that it was bit better than just a mediocre preamp. Funny thing was, I once had to send it back to Roger Modjeski for a minor repair and the store where I got it from lent me a Dyna PAS 2 preamp while mine was being repaired. After about 2 months, I got the Music Reference preamp back and I actually preferred the PAS 2 to the Music Reference. Whether the PAS 2 or PAS 3 are mediocre products, whose to say...I thought they were absolutely dynamite sounding and I would take one over a B&K Pro 5 or 10 anytime. But that's just my preference.

I agree with you that the Luxman pre that I had was mediocre but the Acoustat pre had a most wonderful phono are also correct in that I never did own an ARC preamp; however, a friend of mine owned an SP6B and another an SP9 and I once auditioned an SP8 for about a week but ended up preferring the Music Reference preamp.

My comments on SS ARC preamps came from an old Absolute Sound magazine that did a special article on ARC gear. They said that if you go SS with ARC products, get one of their SS amps and stay away from their SS preamps. I also remember reading a very luke warm review of their SP4 SS I figured the SP7 was in the same league as the SP4 according to TAS's comments.

Regarding my impedence mismatch comment, I'll admit, I'm not the most technical person, I don't know how to build or repair amps, but have been reading hi end Audio magazines for many many years. I just thought with the sensitivity of Klipsch Forte's, you didn't have to worry too much. I never gave a thought to impedence mismatches when I mated the ST140 with many other preamps - it always worked fine...

From all of the audio magazine subscriptions that I've had over the years, I've become quite knowledgeable about used gear and have always been very fortunate to be able to put together wonderfully musical giantkiller systems for peanuts...some might say my system is mediocre; however, its very musical and satisfying to me :)

Tabascokid, I disagree with Lou_setriodes. Keep in mind some people have better taste than others and all preamps mentioned by Lou-setriodes are mediocre at best. Also, his comment regarding your Klipsch speakers and mismatched impedance with a tube preamp makes no sense at all and I doubt he has ever owned an Audio Research preamp in his life.

You can't go wrong with the same brand amp and preamp. You will hear a rightness to the sound with like brands.
Hi T-kid,

FWIW, I owned an ST140 for many years and mated it with several different preamps from a dyna PAS 2 and PAS 3, Luxman, Acoustat TNP, and a Music Reference RM5 mkII. All sounded great with the St140. The St140 was always considered a "giant killer" and is a great sounding very tubelike sounding amp.

With the Klipsch Forte's, I wouldn't worry too much about any impedence mismatch with a tube preamp, and being in this hobby for over 25 years, I totally disagree with Rrog's and Upstateaudio's remarks. From reading their remarks, it sounds like they've never tried their B&K with any other preamps other than B&K; however, I have and with great sucess too.

I would not recommend an ARC SP7 as the SP7 was SS, and ARC's solid state preamps were nothing compared to their tube units. Also, at $800, you could do far better than an SP7. Please let us know your budget so you can be better advised,
I'm learning and was recently exposed to this. So you should match a preamp with relatively low output impedance with the SS's low input. Any rules of thumb to go by on this, like ratio's or either not to exceed?

I must admit, It sounds really damm good thru the Newcastle's pre, especially hooked to the Forte's (Many HiFi's shun them). Not harsh, great mid's. Percussion is repro'd very life-like. Sounds like there's a drum set in the living room. And the bass must have been canned and shipped in.
My local guru at Wilson's audio highly recommends ARC. He has a SP-7, recently serviced, but the $800 tag may be a little steep right now. I do want to minimize swapping components, as I can see you can spend more $ if you don't hit the right price point.
No oil in my morning coffee... yet,
Walter in New Orleans
I 2nd Rrog's suggestion. I had a B&K Pro10MC Sonata paired with an ST140 for over 8 years before I started continually cycling equipment in and out of my system.
I owned and enjoyed the ST 140 for a while. I thought it was very musical and had surprising bass slam. I used a pre amp section of a NAD integrated and a McCormack ADL until I upgraded to a McCormack amp. Experimanting with a tube pre amp would be cool-maybe a used CJ PV-5 or ARC SP-6. They would give you a phono option too.
Before considering a tube pre, consider the relatively low input impedance and soft lower end of the B&K ST 140.
B&K Pro 5 or Pro 10 and you are guaranteed good sound. Anything else and you are taking a chance.