preamp inverts polarity


I have a DeHavilland Ultraverve 3 preamp that inverts polarity.
my problem is my speaker cables, the negative cable is designed for negative terminal connection as is the positive cable is designed for positive terminal connection, so reversing the speaker cables defeats the design of the speaker cables.

what am I to do ?
128x128mboldda1
geoff, read their posts again...they said “ decompress” air not compress. Either way, you’re correct about how vacuum is obtained. 
I’m still stuck on that single ended amp remark...😁
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@kalali

Just to be clear here, Push-Pull amps can be class A and also all triode. The 'air is single-ended' thing is a bit sketchy and also a bit of a red herring, since air has nothing to do with how amplifiers operate.
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Even if what you say is true, which I actually doubt, it would not change the fact that at least 50% of CDs are mastered in reverse Polarity. SETs don’t magically counteract Polarity. There is no balm in Gilead. Not to mention the fact a lot of people don’t like the sound of SETs.