> "I always run the speaker line out to a switching system, and I terminate that line in a load safe for the radio. Then I bridge off that line with either a good big speaker and audio amp, or headphones."
A while back, I found a used broadcast-quality 8 x 8 audio matrix switcher, with built-in high-quality speaker amp and digital telco hybrid. Its a Gentner/ClearOne XAP-400 and typical cost is USD $60 through the big auction site. The older model is the Gentner AP400 but is essentially the same unit and can be purchased for even less. New, these units sold for nearly USD $4K just a couple years ago. Switching across the matrix is accomplished with free PC software available from the ClearOne web site. A block diagram appears on the PC screen and one clicks on each functional block to make switching changes. It's a very intuitive and graphical switching diagram. Routing, compression, EQ, and multipe switching patterns between balanced and unbalanced audio is accomplished with a couple mouse clicks. These units also contain high-quality mic preamps (software switchable for either mic or line) with selectable phantom power for condenser mics. Each input contains a true, 3-stage instrumentation op-amp. This makes connection to either balanced or unbalanced sources very easy with predictable results and minimum common-mode issues. For roughly USD $60 each, these units are an incredible deal for folks who have been considering an audio matrix witching switching system. The speaker power amp and a digital telco hybrid are a bonus. HF phone patches aren't too common these days, but the Gentner digital hybrids are fully automatic and dynamically adapt to each phone line for maximum trans-hybrid loss. I've configured my Gentner unit with a desktop DTMF control pad sold by JK Audio. A picture of the Gentner and JK Audio devices can be seen on my QRZ.com page. Multiple Gentner units can be linked together and I imagine for a large contest station, nearly any audio combination one could think of can be switched. My plan is to integrate a pair of XAP-400 units (16 x 16) with W8ZR's new StationPo II device. If you've not yet seen Jim's amazing station router, have a look at the link below. A complete write-up will also be available in the upcoming August issue of QST. http://www.w8zr.net/stationpro/index.htm Paul, W9AC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
