Brauser gives good advice. If you are hassled by a SF amp then you should back away at this point. Do the tube pre with NOS tubes mated to a SS amp and you'll be happy.
You want happy? Sell the SF and get a Supratek Chardonay pre, drop out the stock 6SN7's for VT231's, get a Pass or Plinius MkIII or higher amp and we'll never hear from you again.
You want happy? Sell the SF and get a Supratek Chardonay pre, drop out the stock 6SN7's for VT231's, get a Pass or Plinius MkIII or higher amp and we'll never hear from you again.