what tubes to use in manley steelhead rc preamp


want to experement with tubes in my steelhead rc any sugestions thanks
autoguy10
My use of the 5687/7044 variety tubes has been the different than Rgurneys. I like the GE7044 better than any other 5687 type tube but the Bendix 6900. I have never had noise issue with them at all. I've used them in CDPs, headphone amps, and my Manley amps I use now. At less than 20.00 a pop you should try them out.