Single high voltage cap vs 2 lower in series for split rail power supply?

I am currently working on making an aleph m amplifier and am working on the power supply. I have some caps that are rated at 63v and this value is much higher then what my rails are for the amp. It runs at plus minus 17 volts. I could be wrong but could I not just put a cap from the + 17 to the – 17 as it would only be seeing 34v and that would be much lower than the rated value and would give me more capacitance then if I put 2 of the 63v caps in series. I looked for a few hours yesterday and could not find an answer that made me feel assured.I am currently working on making an aleph m amplifier and am working on the power supply. I have some caps that are rated at 63v and this value is much higher then what my rails are for the amp. It runs at plus minus 17 volts. I could be wrong but could I not just put a cap from the + 17 to the – 17 as it would only be seeing 34v and that would be much lower than the rated value and would give me more capacitance then if I put 2 of the 63v caps in series. I looked for a few hours yesterday and could not find an answer that made me feel assured.