I am running an ARC VS115 with closely matched cryo treated KT150 tubes . The eight main power supply capacitors were recently replaced with Mundorf HV Mlytics ( 680uf 450V) with the original Relcap 2 uf and /. 1 uf bypass caps retained. Sounds amazing and KT-150’s are a very significant sonic improvement over the KT120’s. This ARC VS115 amp has also had it’s power supply ( rectifier high voltage stage with Cree Schotkys) and power regulator diodes upgraded ( vishay high speed) as well as the coupling caps upgraded to TRT Stealths ( same high end caps used by ARC in production). The KT120’s sounded great in this amp but the KT150’s are in a totally different league. The main power supply capacitors absolutely need to be replaced for the KT150's to sound their best in this amp. The bass improvement is dramatic with the KT150 upgrade. To the best of my knowledge ARC has not stated that KT-150 tubes can be used in the VS115 so I am just stating they worked for me and my VS115 is now one of the best sounding tube amps I have ever heard ! The preamp driving this amp is a Primaluna EV0 400 upgraded with vintage Brimar and Phillips NOS tubes using balanced connections. KT150 tubes from Upscale Audio are matched. Amp is on a 3D Siesmic sink pneumatic platform. Happy listening and e-mail me with questions on this application if interested. jackweston@comcast.net
