Sparky Mark

If you don't like Charles Berthoud, just don't watch his videos. Simple. That's the point here.

That sounds like the amp is going into protection mode for some reason. If an amp cuts out, then recovers after a pause or being turned off and on again, it might be behaving exactly as intended. One slightly unusual aspect of these TB heads is the apparent need to select the correct speaker impedance with that 8/4 ohm switch. Are you 100% sure the switch was set to the cab's impedance?

Whenever I've heard them at pub gigs I thought they sounded pretty good and quite similar to the AD200B, which is often accused of having the same limitation. With the passive tone stack set with mids full up, bass and treble fully off, this head is fairly neutral and does convey the tone of whichever bass I've used at low volume. Of course I've only had it for a day but I can already appreciate the raw power of the output stage and looking forward to a proper test on a gig. I think the Clean switch is an excellent solution to the MK1 one sound character; now it has (at least) two!

I was curious why the OTB has an impedance selection switch on the back panel? I found a Bass Gear Magazine (Issue 6) review of the OTB MK1 that explains why. A very interesting feature of the OTB is that its output power into 4 and 8 ohms is 500 watts for both loads, unlike most solid state amps that give lower maximum output into higher impedance loads. So this is truly a 500 watt head, even with a single 8 ohm cab. Clever!

It's a MK2. (It's printed on the PCB's if you zoom in).

I should add that mine was bought second hand and dates from 2018. I cannot guarantee that Orange still makes them like this, but I think it's very likely.

I've just bought Pete's Orange Terror Bass amp. Great communications throughout. A thoroughly reliable Basschatter.

Having opened my newly acquired OTB MK2, I was (pleasantly) surprised to find not one single surface mount technology component on any of the printed circuit board assemblies. Orange has designed its own 500 watt class D power stage and used through hole components throughout its build. Before the experts chime in about increased reliability and the other numerous advantages of SMT, I know already, it's just a feeling of nostalgia from when I designed my first PCBA's back in the 1980's. I had no idea any mainstream amp manufacturer (I think Orange just about qualifies) was still building 100% through hole products.

I agree that the wear is fantastic, but I do wonder how any bass gets that level of distress if treated with a modicum of care?

Looks genuine to me. Does FB indicate what year in the 70's it was made? I think custom colours have been available most eras, at a cost of course.

My bad.

Maybe, but if the pots are original, it's a 1967 bass at the earliest.

Possibly the worst soldering I've ever seen, plus this pot is clearly dated 67.

I'm surprised you say there's not much online about the AD200B? There's loads if you search. It's the best compromise between a sensible weight and giggable output all valve head still in production IMO. I'd recommend a pair of ceramic 210 or 112 cabs. There's just something about ceramics that neos don't have IME. There's no science behind my opinion, just my ownership experience with ceramic and neo Bergantino cabs. I'll never lift another 100lb cab but two 50lb are still manageable. The day I can't lift 50lbs, I'll know a 200 watt all valve amp isn't for me either.

CS 62P; there's a few clues to identify.

Not so much the modern replacement sets. There's loads of photos online of the CS 62P pups with plain black undersides. See Thomann for instance.

Pretty sure it's a genuine Fender pickup. The cloth wires, raised pole pieces, the small circular indent between the two centre pole pieces and brass plate look like Fender CS 62P to me.

Ah, understood. There's no reason to suspect the L was left off the very detailed receipt or credit agreement, so probably a 1961.

I'm probably misunderstanding your comment but L serial number plates started being used in 1963.

Thank you Pete. I've arranged to see a property next weekend in BSE so will likely stay overnight, allowing me to check a few venues.

Anyone know about the Bury St Edmunds music scene; like if it has one for instance?