No.
The balanced
output on headphone amplifiers are typically
female so the end of the cable that connects to it should be MALE. This connector will be dual 3-pin if the headphone amp has dual xlr connectors or single 4-pin if the amp has a single 4-pin xlr connector.
The end of the cable that connects to the iESL should be 4-pin xlr FEMALE. The cable that
@alexdemaet posted is incorrect because the 4 pin xlr connector end that should be attached to the iESL is MALE.
Assuming that the headphone amp to be used has dual 3-pin xlr female outputs, what
@alexdemaet needs to use is a cable with 2 x 3-pin xlr Male to 1 x 4-pin xlr Female.
Note that if the headphone amp outputs are at the front of the unit (as most are) then a 1 foot length might be a little short. I would get at least a 2 foot length to be safe. The connection will work if the amp can produce enough voltage swing to create a reasonable listening level with the estat headphone.
Hope that is clear.