Mine too are hard work, and I too question whether I'm hearing a difference. Don't know if you've lost it or never had it. :-) I know I've never been a GEA; I have to work to hear differences in cable, electronics, etc.
After conditioning it for days with my VCR driving an input on my preamp, I insert the new cable in the tape-monitor loop of my preamp. (This TM loop contains no electronics.) I determine if the insertion of the cable is audible. If it is, I reject it immediately. If it's not, it has passed the first test and I then replace my system cable with the new stuff, and also reinsert the 'old' cable to verify differences. It's still hard work.
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After conditioning it for days with my VCR driving an input on my preamp, I insert the new cable in the tape-monitor loop of my preamp. (This TM loop contains no electronics.) I determine if the insertion of the cable is audible. If it is, I reject it immediately. If it's not, it has passed the first test and I then replace my system cable with the new stuff, and also reinsert the 'old' cable to verify differences. It's still hard work.
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