Bogen Step Down Transformer T725

These are handy for matching various impedance at audio frequencies. I used mine to step down the headphone impedance of a vintage Heathkit HW-8 radio from 1000 ohms to 16 (to match my Sennheiser headphones). Works great. Very inexpensive solution and quite fun for experimenters who want to just learn about audio impedance.

Good for antique radio repairs

This matching transformer is a good buy. It does not come with schematics or instructions, but you can get these online. If you are using these to power crystal radio speakers, be sure you get low-wattage speakers with fairly rigid cones or you may not get the audio output you want.

I bought two of these transformers to match a PM speaker to a 1929 TRF set.. They seem to do the job, but figuring out the wiring was a pain.. no diagram and no labels..I picked my leads using Ohm readings found online.. The lead colors may or may not be correct(mine were not), and for that they get three stars.. but they worked for what I wanted to do..

I bought this a few years ago. Today I took them out just to play with. audio quality was pretty good. And I love the flexibility to match impedance. Great for fun experiments and audio DIY stuff.

No information came with this transformer the first time I bought one. I was able to find some information on the internet as there are a lot of wires coming out of this item. Just the right size to replace an old audio transformer that was open in an old RCA AR-8712 RDF. Used the T725 to run an S-meter and the old 4 ohm speaker. Amazon is the best place to buy one as you can see all the different prices without searching and checking a bunch of web sites.

There are color codes on the transformer but they don't match the wires.

I got this to connect a 6ohm speaker to my hallicrafters super sky rider tube shortwave receiver. Once I figured the wires out, I hooked it up and it works just fine.