ARC sp9,Krell ksa250,Infinity Kappa8. Problems?

Hello! gedman3@earthlink.net: I was wondering if you help me: I have an audio research sp-9mklll preamp. when playing in stereo mode only left speaker works:When switching mode to left channel both speakers operate: When switching to right channel neither speaker works!Any THOUGHTS! Thanks! Horseshoe 6391zre@optonline.net

i own a krell ksa250 and electrocompaneit ec4.7 and sim audio moon cd player drive my martin logan sl3 speaker it give me a very good combo and sweet sounding if combind all of these set it cost more than $15000 but my other set sound better than these krell set and cost a lot less i mean a lot less and sound wonderful lot of head room and clearity...

I am new to this forum, I have owned 8 Kappa`s for 20 years.
Many $ spent, went on amps for these speakers.I cannot however
speak of Krell, or AR. They were ( Carver TFM25, bi amped with Adcom GFA 555, Pre amp then was a Carver CT7) in all possible configurations. Then I made a complete trade For NAD Stuff. The best Preamp NAD made in 1992, I cannot remember the model#. Paired with 1 SINGLE Amp, The NAD 2200PE. It sounded much more Dynamic, and robust than the 2 amps previously mentioned. The salesman were I got this NAD stuff, made me promise to listen to this for 2 weeks, before he would sell me another 2200PE. With 2 2200PE amps I was actually Driving my Kappa`s with some authority.
Then I stepped into the TUBE Stuff.I Bought Cary Audio.
(2) CAD 40m Mono blocks, with an SLP 90 TUBE Preamp.Only 40 watts per side,but MASSIVE TRANSFORMERS. I could Drive them,
with the same, if not more authority, but the Beauty of the timbers, and ringing of guitar strings on this invisible soundstage took on a new and totally impressive (GOOSE BUMPS)sound. I Paid around $3600 for the 3 Cary pieces. This set-up was by FAR the Best My KAPPA`S ever sounded. And I am a very critical listener. I Guess, I am suggesting that you try some TUBE stuff, before your purchase.I am not condeming solid state equipment, but an A vs B comparison is not valid in high end audio. I had Great salesmen back in the mid 90s, that let me listen for a couple weeks, before any transaction was made. Just my 2 cents.

Before looking for qualified amps I would suggest to check if he crossover network is OK.
Krells are good for the bass, but not for the top end. You may find some old Thresholds for the top end and use a tube as your preamp- then all should sound well.

I'm currently using 2 KSA-250s in my system with an ARC Ref 3. It is a great combination. The KSA 250 is a legendary design. To me, it does not sound like a "newer" Krell. I much prefer the KSA 250.