music, guitars & other obsessions


NAD: Marshall 5212

Picked one up yesterday, it’s an old solid-state model ca. mid-80’s – one of the JCM800 models, since I have not played an actual tube version of the JCM800, I don’t know if the SS version even comes close to the sound that it produces. Anyway, to my ears, it sounds better than the current SS amps that Marshall are selling – doesn’t hurt the amp is loaded with two Celestion G12M-70’s.

Marshall 5212 Combo

Marshall 5212 Combo


Steampunk Guitars by Tony Cochran

Very, very cool!

Guitars for sale – Tony Cochran Custom Electric Guitars.

The Rigs

The Rigs. Great blog about guitar rigs with nice diagrams and live shots.

Sample rig diagram

AX84 SEL Build

I finally got around to wire up the SEL, I had the parts mounted on vero boards, so it was just a matter of transfer them to the turret board. Here is shot of the unit under test before the transplant.

SEL under test, parts mounted on the vero board

Getting the turret board ready…

Drilling the turret holes

I had Lao Hu made me a pair of turret staking tool out of bolts (not shown). The bolts were a bit too large and interfere with mounting turrets that are too close together, need to get new ones made eventually, anyhow, I managed to get most of the turrets in without much issue.

Turrets are mounted on the board.

Voila! turret board ready for wiring.

Completed Turret Board

A shot of the finished board mounted in the chassis.

Wired and ready for power-on test.

Princeton Shanghai Special & 1×10 Cabinet

Finally loaded the Princeton head into a tweed-like chassis, it sits on top a 1×10 speaker cabinet, based on the AX84 1×12 design, the panel is large enough, so I could fit 2×10 or 1/12 in the cabinet if I want as well. Currently, I am using Eminence Raging Cajun speakers for the build, the speaker is not yet broken-in, but it already sounds better than the 8″ from the Marshall MG15 cabinet, which comes as no surprise since the one from the Marshall is just a cheapo generic driver. Also I have not yet put on the back panel, that will also alter the sound somewhat, so more experiments to come later…

Amp Head

My first attempt was simply to stuff the head into the head cabinet, it did work, but it would require new grill to be made and the blue chassis color clashed with the tweed theme of the cabinet…

Shanghai Princeton Special - First Try

I then removed the two mounting posts from the rear of the cabinet, so I can mount the head sideways, that worked a lot better, I can also use the original grill, thus preserving the tweed cabinet theme. It actually worked out very well, I am not sure I would even need to put the back panel on… Perhaps just put on the bottom plate of the head, to keep high voltage out of harm’s way.

Top View of the head inside the cabinet

Front of cabinet with original grill

And a shot of my rig.

Guitar Rig

Tube Breadboard Power Supply

While I managed to build the Fender kit and Fat Booster/Bastard without much difficulty, after going through the various DIY sites, it is pretty clear that I need more tools! The selection of tools available to the hobbyist is quite daunting, one can easily spend thousand Dollars not Yuan on these things. Of course, it is possible to do the job with your everyday handyman tools, which I already have, but to get decent results from them, one need to be very creative and/or very good with tools, which I am not, so the solution is to get “professional quality” tools to compensate for my own shortcomings.

It has taken me awhile, but I finally managed to put together the power supply section for the tube breadboard. The delay was primarily caused by all the hardware – the frigging screws, washers, connectors, etc. It was very irritating that small things like this could be such a PITA, wiring things up was a breeze compared to getting these parts, perhaps it was because I am starting from scratch, and I had no spare parts from other projects, anyway, I think I have actually spend more money and time on sourcing these buggers than the active components! WTF…

As shown in the shot, the power supply except for the tube rectifier and the power transformer is housed in a surplus power supply casing, with the silicon rectifiers, caps, and resistors mounted on a perf-board, the solder pads on these perf-board are totally shit, so basically the whole thing was wired point-to-point… All the connections to the board are available via connectors, so it will be easy to dis-assemble, or modify later as required. The case also puts high voltage out of reach… All the external connections are routed to the terminal strip on the back of the power supply module, and makes easy connection to the tube amp bread-board module.

Here is a shot of the power supply module, ready for the amp board…