Transformer Coupled Interface Type 1 Unbalanced to Balanced Converter

I've been building these things for years and after so many customers suggested that I should release my TCIs commercially, I decided to take the plunge. So here's my  Transformer Coupled Interface Type 1 which is a 2-channel, passive, unbalanced to balanced converter.

TCI started as a problem solver in my own studio. Before long, friends asked me to build TCIs for them and then they got the attention of musicians, engineers, producers and even audiophiles, further afield. With a proven track record, there are already hundreds of these boxes all around the world, some of which may be over twenty years old! Out of all the things I've built over the years, people seem to love my humble TCI.

Making a commercial product is a great opportunity to offer a truly high-specification device, to a wider audience and I'm very proud to have squeezed all of this in:

NUMBER OF CHANNELS	2
FREQUENCY RESPONSE	30Hz – 30kHz
INPUT IMPEDANCE	6.4kΩ - 6.5kΩ
OUTPUT IMPEDANCE	<600Ω
INPUT CONNECTIONS	2 x ¼” (6.35mm) 2-pole jack socket
OUTPUT CONNECTIONS	2 x 3-pin male XLR socket (pin 2 is in-phase)
DIMENSIONS	(L) 80mm x (W) 80mm x (H) 47mm inc. feet
WEIGHT	<350g

The title says it all and you've just read the specifications but there's even more information about my Transformer Coupled Interface Type 1 unbalanced to balanced converter in my post, here.

Yes, I know; what about the 'Type 2'. Well, the Type 2 is (you guessed it) a passive 2-channel balanced to unbalanced converter. Indeed I've also built a few of these. I'm going to see how the Type 1 does before I consider releasing the Type 2.

There's also a Type 3. That however, is for another time... and another post! 🙂