There is also a big difference in the sound they produce, especially when pushed hard. Cathode-(self-)biased amps have a very characteristic type of compression when driven hard, caused by the bias voltage being altered by the signal level itself. This is what's usually meant by the "Class A" sound,...

Don't put down your Peavey - it's a well-made, good-sounding, reliable amp... and you might be surprised how very similar it is to the Marshall in build quality methods, component types and materials. That's not a put-down on Marshall either - both are well made mass-production amps designed with an...

Lots of questions and some good ideas about things to check! Yes, the Powerbrake's orientation could make a difference. Looking inside mine, the plane of the transformer coil is vertical - which is the same as that of the coils in a guitar pickup when you're standing playing it, so coupling is likel...

It does sound most likely to be the power supply, yes. I would confirm it by trying one pedal on a battery before spending a lot of money on a new power supply though, just in case! If you do need a new supply, the Voodoo Labs one is excellent. I also agree with DeanM that the Boss V-Wah (and other ...

I don't think it's a fault as such with the Powerbrake - it's just a consequence of the way it's designed, with a large transformer. This will radiate electromagnetic energy when it's working, and the pickups will pick this up - it's just physics unfortunately. I do get the same thing routinely when...

It's caused by direct electromagnetic coupling between the amp's output transformer and the guitar pickups - or between the Powerbrake and the pickups, since it's also based on a large transformer and acts like a second output transformer. The giveaway is that in the hum-cancelling positions, it sto...

Don't run the wah in the loop - it's not designed for that signal level and impedance, and it will totally suck tone as you've found. A wah should always go in front of the amp, if possible first after the guitar - although there are some fuzzes that work better first too, so then you have to experi...

It is basically a later version of the 1959 Super Lead - no master volume, so if you want it to distort you'll need an attenuator (or earplugs!). The usual warnings with vintage Marshalls apply - since it's a vintage amp now even if not a small-logo turret-board one - before you take it, make sure i...

You're absolutely right - the key point is quality, not price, and there are plenty of well-made, durable and great-sounding cables (and pedals) that don't cost a fortune. But generally, you don't want the cheapest stuff since it tends to be so for a reason, and up to a point you do get better durab...

Power scaling is different, and involves controlling the power supply voltages in the amp so the actual power developed is lowered, rather than generating the same amount and turning some of it into heat rather than sound. It's more sophisticated and reduces valve wear (and potential stress on other...

Or, it may be that the session involves recording in a tiny room with a live vocal, an acoustic guitar or some other thing that he doesn't want the amp to bleed into. Tone is *not* always the most important factor - it's actually not always that easy to get a great tone onto tape/computer with a mic...

I'm pretty sure the whole cabinet is ply - it says so in one of the reviews anyway. This is hopefully something that will be done across the board at Marshall, at least for the standard ranges of amps and cabs - all the cabs smaller than 4x12"s and several of the combos have been made from MDF for s...

That's far too complex, expensive and unnecessary for four pedals, or even a few more - it's the sort of thing you need if you've got a pedal chain the size of Dave Gilmour or The Edge with dozens of pedals and rack units, because then the cumulative noise, hum and signal loss problem is massive - b...

There's a *lot* in there apart from valves and the speaker. Yes, the white stuff is hot melt glue. It's common (and good) practice on modern amps to stop the caps vibrating and potentially cracking their solder joints. I would actually like to see more... the little blob around the largest filter ca...

So it isn't that... Is it possible to run your pedals on batteries? If so, it's worth trying at least as a test - it's still possible the hum is from poor power supply filtering, or possibly an 'internal' ground loop on the board since the grounds of the pedals are connected both via the audio cable...