My 2 cents on tubes with the 502 and Jolida. The tube combo I liked the most was Mullard 12AT's and Mullard NOS 12AX's in the Pre and Northern Electrics in the Glass FX.
I moved the NE to the 12AX7 position on the 502 when I sold the DAC. The Mullard 12AX7's NOS ($$$) Were not the best for my ears, but when the NE were in the line, they were acceptable.
I moved the NE to the 12AX7 position on the 502 when I sold the DAC. The Mullard 12AX7's NOS ($$$) Were not the best for my ears, but when the NE were in the line, they were acceptable.