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ISO NP126 as interstage

I have a pair of NP126s (ISO’s line out transformer with 4:1 step down) and am thinking of using them as interstage transformers, driving a SE or PP output stage after them for headphones - so gain is not an issue.

Anyone one has tried or see potential issue?
 
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The datasheet of NP-126 says that it will saturate at 10V @20hz. I think it will affect the maximum output power at low frequency. But maximum output power is also not a problem for headphones.
I'm using step down interstage too. A pair of LL1692As configured in 1.75+1.75:1. I think it's a great choice for a headphone amplifier.
 
Indeed not a lot of output to be expected from secondary windings of NP126. For headphones like HD650 though, it can still work out in a 2 stage amp with right tubes.

In fact, my current headphone amp uses a single P2 tube in each channel with Lundahl 2765 SE output transformers in 6:1 configuration (and my DAC has 4v rms max output).

But I also have a pair of NP126s and a pair of Lundahl 2765 PP irons and hope I can put them in good use together in another headphone amp.