“I’ve been doing DJ work for a few years. Recently I decided to spring for a “pro” amp for my system. After getting several adapters and getting it hooked up I am now finding the “pro” amp is not as loud as the old hi-fi amp I was using. I have to crank my mixer to get anything out of it. I thought this thing was supposed to improve my sound. Help.”
This is not uncommon. It probably will improve your sound once you get things set up correctly. Your DJ mixer is most likely set up for -10 dBV operation, whereas the pro amp you purchased is probably set up for +4 dBu operation. These are the two major level standards we encounter in audio equipment these days and they really aren’t directly compatible with on another. For more information on this subject than you probably want to know, check out our dB Summit in the inSync section of our website. It goes into great detail about the difference, why things came about this way, and what it all really means at a practical level.
The Cliff’s Notes version of it that’s pertinent to your situation is this: Your mixer is probably set up to interface with equipment using a nominal signal level of -10 dBV, or .363 volts. You amp is probably set up to interface with equipment working at the +4 dBu or 1.23 volt standard. When you crank your DJ mixer you can maybe, just barely get enough level out of it to begin to drive the amp. As you’ve observed this just isn’t going to work.
The solution is to either change out one of the pieces of equipment for something compatible or get a level matching interface. Now, it is possible that either your mixer or your amp has an alternate set of connections or is in some way switchable to other levels so check for that first. If not, a level matching interface is probably your best bet. These are devices that are specifically designed to change signals from -10 dBV to +4 dBu and/or vice versa. These may use either active electronics (op amps, etc.) or transformers. The transformer units are usually less money and probably not ideal for extremely demanding situations, but for what you’re doing one of those would be fine. Generally these will also balance your unbalanced signal, which will make it much more robust if you find yourself in a situation where you have to send the signal from your mixer a long distance (such as tapping into some type of house PA or something).