Having owned a pair of MD 300s for several years I can only comment on my own personal experience. Get the amps to Krell to have them re-capped. They ALL (Every KSA and MDA series ) need to have this done every 10 to 15 years if they see any consistent play time. Shipping, caps and labor ran me in the area of $1200 back in 2009 for the pair of amps.
The MDA 300 is a very pleasing product. Character of Class A SS but a very refined and easy balance in tone. I used them with an Ayre K1 pre to excellent effect. Use of a differentially balance pre always sounded best in my system. Speakers ranged from Apogee Studio Grands, Dynaudio Contour IV ( early BIG ones ), to JM Labs Mezzo Utopias.
To echo Lloydlee21, the Krell house sound from that era is "
"unbelievable composed and controlled into any load, visceral bass, warmer mids than in newer evo-generation krells"
Power cords will make a difference to the MDA 300 but not nearly as much as making sure you have a dedicated 20 amp or 30 amp AC line for them to run on. I ran an 8 gauge 60 amp service to my room and the sound of the entire system improved. Every note sounds more free and effortless. Dynamic contrast and shading became more evident and natural. Ease and control improved as well.
To borrow a current commercial phrase:
Feed your Krell. Feed it!
