Hi !
12 year old topic, I know, but I got one of these in a trade, among other kind-of-broken stuff, and thought it could help , espeacially if you like hunting for bbd chips.
Mine is a Phonic Rock-box, but I've read somewhere that it's similar to other models (ROSS Rockbox, Nobels sound studio, JHS Rockbox, etc), probably Taiwan made and rebranded, from the 80's.
It's basically a preamp / headphone amp with gain volume and comp control, 5 channels : normal, clean1, clean 2 (all of them just different eq of the same channel imo), OD and Distorsion. Switchable delay (very short, more like a spring reverb) and chorus, both with a level knob.
Mono or stereo in, mono or stereo out, send and return (since it's a preamp I have no idea where the loop goes in the signal chain) and a footswitch jack to change between any channel and the distorsion one.
+and -6V symetric power supply with a 3.5mm stereo jack, or you can use it with 8 1.5V AA batteries.
Belt clip, of course, because you want to carry that around and it was made in the 80's.
I've seen some online with a gate and tone control. apparently it was used by Def Leppard on "Hysteria".
I was about to toss it before fixing it, but when I realised it was just a power supply problem I gave it a try... and honestly it's really fun. Way better than the headphone outputs on my amps, and way more versatile and more importantly portable.
Oh, and for all you scavengers out there it's all analog so you'll find several chips in there ! A lot of JRC 353 D, some CD40something, three MN 3101 and even better : two MN 3007 and an MN 3011 !


