Categories
Custom Fabrication

“Detroit Boxes”: Motown-style transformer DIs

Detroit Box #001 featuring UTC Ouncer Transformer and O-17 magnetic shield

Last year I found myself with an excess of nice vintage 1:10 and 1:12 audio transformers, so I figured I would make some “Motown”-style passive DI boxes and see how they sounded. I built all of these using genuine 1960s era transformers, NOS Allen Bradley carbon-comp resistors, and NOS vintage hardware components in order to make something that ‘looked and felt’ like the sort of thing that a studio custom-shop would have built in that era. These aren’t copies of the Motown box – that piece used a particular model of transformer which I did not use, and I had my own aesthetic directions to pursue – but like the original units, they have that higher 1:12 ratio, variable defeatable pad, bi-directional operation (for use as a ‘re-amp’) and ground lift switch.

In the past I generally built my DIs with 1:5 or 1:8 ratios, so I was curious to see if the higher ratio gave a more open, detailed sound while still allowing for a sufficiently good signal-to-noise ratio. After building a half dozen of these things, I can say that yes they sound great. Here are a few examples of the units I built.

#005, again with a UTC O-series and shield
#006; this one features a large Thordarson 1:12 transformer

2 replies on ““Detroit Boxes”: Motown-style transformer DIs”

Hi Evan. These have all sold. Via instagram. There will be more. The best way to get one is to follow my account there. They tend to sell in about 5 minutes. CR

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.