Yes, inductors for the original Pultec.
Since the Triad HS-29 was unobtainable, I used the Sowter transformers suggested by Drip. That interstage is the 9330. It's 2.5K primary 10K secondary. The HS-29 is 20K primary 80K secondary, big difference. Also, I started out with the Vintage Windings inductor, which has all sorts of problems. A GroupDIY member suggestd the Carnhill inductor. With no other changes but the inductor, using the Carnhill cut ringing by half. But still could not control the ringing using the 9330. Ended up using UTC A18, which is 15K:80K. With a 220pf 18K Zobel, ringing was controlled. I measured a Pulse Techniques repro (couldn't find an original unit locally to measure) and the Carnhill freq centers and slopes are very, very close to the Pulse Techniques unit.
In the midst of this test, I contacted Sowter about the problem I was having with the 9330. They were very responsive and ended up sending me their new interstage/phase splitter to test, the 1475. It is a fine transformer. I was able to control the ring with it using 330pf 4K Zobel. I could likely improve that Zobel (less loading) if I put more time into it. But by that point I had drilled mounting holes for the A18 in the chassis and was frankly tiring of chasing the issue. But I would not hesitate to build with the 1475 and the Sowter input and output transformers. I have two units. I modified one using UTC A20 and A18, and the new Cinemag S217D replica. The other had the Sowter input, 1475 interstage and Sowter S217D substitute, and it was very difficult to tell them apart. The Sowter iron sounded great in comparison. In fact, had I not already bought the UTC and Cinemag transformers, I would have just replaced the 9330's with the 1475's and called it a day.
