My personal preference would be to migrate those cans over to a balanced output for more power. However, in this scenario the DAC wouldn't be balanced.

I know iFi offers balances DACs/Amps. I wonder if selling your current amp and migrating to a stack that moves you to balanced + xbass would get you what you want. You'd also need a new cable.

Can you run that amp as a DAC only and use the pre-outs as line outs to a more powerful amp?

It’s sold out boys. Put the credit cards down.

Assuming your comment is tongue in cheek, but they're well regarded. Their name is intentional.

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