DIY rotary DJ mixer [some technical stuff too]

The year 2018 has started off slow...

Anyway, I decided to make a long-time dream come true and finally ordered some parts for a rotary DJ mixer. I used to design these things back in high school but never got around to making one.

Here's some of the parts...

A mic channel and RIAA preamps made from kit.

Here's a passive summing stereo mixer which is made from tag boards, some wire and 10K resistors. The lower part is for ground signals.

Here's a picture of the initial assembly of the unit with the input modules in place.

..and some more wiring. In the lower right corner of the case there's a toroidal transformer which isn't included in the final build though.

Here's a view of the front panel without the monitoring section.

Another picture of the insides with monitoring section and an unbalanced booth out

Here's a picture of the "finished" build.. I've mounted a power-on LED in the front panel since and made some other modifications to the unit.

I'm still working on some stuff such as the PSU and a few other things. Component-wise it's Velleman mic, RIAA and line preamp & headphone amp kits, ALPS volume pots and Lundahl output transformers.

You can follow the build in GroupDIY

PLUR,

-ef

EDIT : Here's a rough circuit diagram/schematic for those who are interested..

I have to add that it's not 100% correct though because I drew it from the top of my head but it should give a vague idea of how it's wired.

EDIT 2 : minor fixes..

EDIT 3 : Here's a picture of the EQ module..

#diy #rotary #dj #mixer #velleman #alps #lundahl #groupdiy