Dr. Perry Alexander

The University of Kansas

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Prototype setup

I want sound. Having sat and looked at these speakers and amps its time to make some sound. Thus, I decided to set up a prototype to experiment with the various components. Not much sense in setting up a full 5.1 system if I can’t do stereo, so I decided to go that route first.

To do this I need to connect my Audio Research preamp to the inputs of the DSP, the DSP outputs to the ATI amps, and ATI amps to the speakers. The speakers are 3-way with highs, mids, and lows all driven by separate channels on the ATI. Thus, 6 channels on one amp for stereo. I decided not to hook up the sub for now. First, the preamp out to the DSP in. The DSP uses Euro style connectors. Nice to use, but difficult to find cables for. Output from my preamp is balanced and the DSP takes balanced in, but I don’t have XLR to Euro connectors. Enter B&H. I ordered some male XLR to Euro connectors and thought I was good to go. The Euro connectors turned out to be way too small, but it was an easy change to put connectors for the 8x8 on. Problem one solved.

Next I wired up the 6 outputs from the DSP to the amp. Thanks to great labeling by Hal, this was a snap and went quite quickly. To make sure everything is functioning and wired up correctly, I used an old PSB Alpha to ring out the amp outputs. Each amp output gets connected to the PSB one at a time to see if I’m getting sound.

Everything is going well until I get to the right channel outputs. Turns out that the lows are not producing output at all. I remember Chuck telling me that the DSP had been rebuilt to repair a dead breakout output. On a whim I tried other outputs from the DSP and found the low right output. Hooked that up successfully and I’m ready to hook up the main speakers.

Final step was dragging 6 pairs of speaker cables from the ATI to the speakers. After connection number 6, the skin is gone from my fingers and I’m ready to not be twisting copper wire. We’re ready to get the first sound out of this new system.

Bingo. First album is Donald Fagan’s The Nightfly. It’s my favorite pop album, plus I pay homage to Chuck who first played it for me sometime in the 80s in TeleImage in Dallas. I immediately recognize something is wrong. Everything sounds tinny. No bottom end at all. So, I decided maybe the subwoofer is necessary. Looked at the DSP configuration and sure enough the lows from both stereo channels are filtered off and run through the sub. One more cable to run and hopefully all is well.

As it turns out, all is way better than well. After jumping up and down in the stereo room for a few minutes and a quick dash up the steps to talk with Pam, it was time to settle in for serious listening. More on that next.