Okay, I don't know how useful this will be considering that I don't have a good point of reference for comparison. I borrowed a Roland SRA-200E 150 watt pro audio power amp to get me going with the DI's. The Roland surpassed my expectations as a loaner. Very good sound quality.
The KingKo KA-101 was clearly better as expected. Listening to classic R&B, quality of the bass to me was the most obvious improvement. My Lover's Prayer by Otis Redding, convincingly puts a Fender Precision bass through an Ampeg B15 amp right in the room. Even at low volume, bass gravitas is realistic some how. I guess that's another striking attribute of the DI's, in conjunction with the KingKo: Striking sound with realistic dynamics at low listening levels. This illustrates the recent theme in this thread whereby less is more when you have speaker efficiency and quality amplification. Where in this world, 12 watts > 150 watts.
Using the KA-101 as a power amp with my Audio-GD Master 6 pre was another clear step up in quality. I would have preferred to use it as an integrated for simplicity's sake, but it was not to be. In combination with Yggdrasil, things were quite good indeed. These impressions were done straight out of the box, with no burn-in.
Of course things should significantly improve even further by swapping tubes. Here is what King recommended in the article's interview:
"I think the amplifier is just fine with the tubes that I supply as they are the Shuguang tubes from China. That said I think there are some big improvements that are attainable through tube rolling. The tubes that make the biggest impact on my amp are the 5AR4 Rectifier and 12AX7 preamp tubes. I suggest the NOS RCA 5U4G which is a 5AR4 equivalent. And I suggest the Gold Lion Gold Pin 12AX7, followed by the Tungsol 803s gold pin and EH (Electro Harmonix) Gold Pin. The EH is inexpensive and can be a little noisier in dynamic passages. There are many more expensive tubes that you may like better but these tubes are very good and quite reasonable. For the 12AU7, I prefer NOS from Brimer and Amperex, and finally I like the Gold Lion EL84s."
Some other R&B classics that showcased a large, detailed soundstage were:
"Trust In Me" and "At last" by Etta James
"A Change is Gonna Come" by Sam Cooke
The Etta James' tunes were eerie. I turned the volume down several times because I was convinced someone was in the room with me.
I'll keep updating as the journey continues. I hope to audition other low watt tube amps to see how things compare.
Bill M
