Author Topic: JHS "Rockbox" Anyone?  (Read 4609 times)

Joe Kramer

JHS "Rockbox" Anyone?
« on: January 22, 2008, 05:55:02 PM »
Hey Friends,

Looking for any info on this unit, a JHS Rockbox, model RBX-2.  Very little comes up on Google, and nothing in SEARCH.

It's similar to a Rockman X-100, with distortion, chorus and delay, but it's in a metal case and has a few more features like FX send, and individual controls for chorus, delay, and compressor levels.  I'm seriously thinking of re-working it into a rack enclosure with all controls and jacks on the front panel, since it sounds pretty good and would be handy for recording.  Sort of an analog POD.   :icon_wink:


Solder first, ask questions later.


Re: JHS "Rockbox" Anyone?
« Reply #1 on: April 29, 2020, 09:35:18 AM »
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 !

Mark Hammer

Re: JHS "Rockbox" Anyone?
« Reply #2 on: April 29, 2020, 11:12:32 AM »
That's a veritable goldmine!


Re: JHS "Rockbox" Anyone?
« Reply #3 on: April 29, 2020, 08:11:51 PM »
probably Taiwan made and rebranded, from the 80's.

I'm going with 1988, either Japan or Taiwan.

Mark Hammer

Re: JHS "Rockbox" Anyone?
« Reply #4 on: April 29, 2020, 10:44:21 PM »
I'd put it a few years before then, based on the use of the MN3011.


Re: JHS "Rockbox" Anyone?
« Reply #5 on: April 30, 2020, 04:04:19 AM »
I'm no expert, but it's my understanding that with the old 4-digit JRC codes, the first digit in the code is the last digit of the year.  Some older electros have common YYWW codes, and I see "880" on one that's partially obscured by wire, and "8804" on another.

Mark Hammer

Re: JHS "Rockbox" Anyone?
« Reply #6 on: April 30, 2020, 11:42:21 AM »
You may be more an expert on this than I.  My understanding was that 3011 chips stopped being produced earlier than that, but I suppose if folks can still get NOS germanium transistors today, then someone making stuff in 1988 can probably get chips that stopped being in production a few years earlier.


Re: JHS "Rockbox" Anyone?
« Reply #7 on: May 01, 2020, 03:44:21 AM »
Here's some more information about the box :