Which pre for a long run IC?

I have a meridan 502 analog controller between a consonance ref 2.2 and hurricanes, which are 5 meters away behind biwired martin logan sequel II's. the sound is thinner across the board as against when my set-up was able to use 1.5m DIY ic's. the long ic's are nordost solarwind. would a different preamplifier help matters out, that is, improve (fatten) the signal reaching the amps? or, should i try different long ic's with their outrageous prices (for wire!). any help or suggestions are greatly appreciated. cheers

The Bryston BP-20/25 (SS)will put out 15 vRMS unbalanced (30 vRMS balanced). The Marsh Sound Design P2000t (hybrid FET/tube)preamp will deliver 8 vRMS (balanced). The are doubtless other good preamps with high output. Both preamps have very low output impedance and can handle long cable runs. FWIW, at five meters, your IC run is not terribly long, but could be a difficult load for a low gain preamp. I connect an older Bryston 11B with 27 feet of DIY Belden 89259 interconnects to a Bryston 14BSST and couldn't tell any difference when compared with a 3 foot IC. If you have noisy AC power or RFI, balanced interconnects would be the best choice.
thanks for your response. and as luck would have it, there's a P2000t for sale here. again, thanks alot.

I think you should use preamplifier with low output impedance such as bvaudio p10or try their sound refiner. Long runs are always problems.