Dear Howard. Grateful for your views as to whether the captioned extension cable (6-pin in/female & 5-pin out/male) will work with a pair of SR-3 earspeaker into the normal socket of a SRA-14s. Many thanks in advance.
I am finding this a very difficult question to answer with any confidence.
First, despite many years of intimate knowledge of STAX equipment (The SRA 14-S was one of the finest preamps I have ever owned, from any maker) I was totally unaware that a conversion cable as you describe existed. I guess neither of us know if it is an official lead, or a DIY job.
I was always taught, and it stood I and my customers in good stead, that you never ever mix headphones with 5 pins with sockets with 6 pins nor vice versa. For a start, the polarising voltages are entirely different. There is some evidence that despite this, that combination will work - for a while. Personally, I’d be fearful of long term damage to the earspeakers.
In your position, I would start a thread on the head-fi forum. I feel reasonably confident that someone there might well be able to give solid advice based on direct personal experience rather than supposition and/or wishful thinking.