I had one with an attached power chord (the older style...but not that old) was noisey and had a whine to the repeats that was very annoying!! It was very noticeable when playing and caused me to get rid of it. Also, the bypass didn't bypass the pre-amp section. From what I've heard, it was caused by the power supply being close to the other components. I've had better luck with the newer style, quieter and they bypass the pre-amp...
Different BBD chips.I think MN3005 chips in the older ones,(someone will no doubt correct me if that's wrong).
I have a new old stock Digital Multi Meter that isn't true bypass but works pretty well for.......huh?......oh.....DMM doesn't mean Digital Multi Meter here. Never Mind. I guss I've lived in the DIY world too long.
My late 70's model has less white noise and the modulation is "swampier" not true bypass though ... but a looper fixes that.
