Dan Dare

This is quite a useful guide - Understanding Guitar Pots and Caps | Potentiometers Capacitors Wiring (artisanluthiers.com)

I use 5" drivers with mine, but you need lots of them (I have up to 20 at my disposal).

I don't mind the fact that an instrument is dirty/not looked after as long as the price reflects the fact. No big deal to clean it and happy to do so if it means I get it for a bargain price.

Sadly, it was the whole cab.

I too had a Peavey BW 15 in an old Fender 1x15 cab. Great speaker until some little scrote pinched it.

That's surprising if it's hypercardioid. Given that a snare is loud and cuts through, you often don't need a particularly great mic' on it, especially for live use. That's why the good old SM57 often gets used for the job. It's pretty insensitive to anything that happens more than a couple of feet away and the response falls off sharply at both frequency extremes. They're not expensive second hand. Worth trying one?

I had an SVT210HE, which I really liked. Not too heavy, portable and small enough to fit in the car boot. I ran it with an SVT15E, which worked well, but I really wanted another 210HE (which were no longer made). I eventually sold both and got what I have now (which I'm very happy with, but they cost me quite a bit). And what do you know? I came across a mint used 210HE a short while later. Sod's law.

Probably not. You may find that if using a lot of gain, which means the tube requires more juice, the 200ma supply would not be beefy enough. Apart from that, it shouldn't make much difference.

They normally just drop into the covers. They're not fixed. So if you do have an issue, just put them back in the originals and keep schtum when returning them

Exactly that.

It's a free country and you're welcome to do it any way you like. You may or may not get it to work doing it that way. Bill was explaining the way to get the best result. Ideally, you need to be able to control the frequency ranges and relative amounts of power going to the subs and tops. If they are very different in terms of efficiency/sensitivity, you will struggle to balance them. Used power amps (especially old school - i.e. class AB/heavy) can be picked up very cheaply these days, so it's worth picking one up. An inexpensive basic crossover from someone like Behringer isn't going to break the bank, either.

Much good advice above. A 15 won't necessarily produce more lows than multiple smaller drivers. Chris B raises the important point of efficiency/sensitivity - how much acoustic output you get for a given input power. That is down to cab design, as well as driver type/size. Simply adding a large single driver cab won't necessarily give you more of what you want, especially if it produces a lot of subsonic or infra bass, which can cause issues with the PA via low frequencies travelling through the stage floor, up mic stands and into mics. It can also muddy the sound in the room.

Toilet seat "was brown and worn, now refinished". I'll, er pass, thanks.

Yep. They will probably move production to somewhere cheap, but continue to charge the same prices. Even if they don't lower standards, they will still be quids in. I happily paid the high price (compared to other brands for an equivalent) for an AG700 because I liked the fact that it hadn't been built by children in the Far East earning minimum wage.

Same as. Can't stand the over-hyped, frantic tone of many YT vid's. No doubt people making them have been told you have to "grab" or "engage" the viewer. Just pees me off and I'm more likely not to watch.

Given the price of the amp, changing valves (or at least, more than one of them) would not be a cost effective option. Assuming it has separate pre and power sections (it may not at 5w) you could look into substituting the preamp valve for a lower gain version.

I'm in a similar position, having played mandolin and guitar for 30 years. I prefer to use my fingers on the bass if I can, but I find there are some approaches that really demand a pick. It's more to do with the attack and shape of notes than the tone. You can approximate it to an extent, but really, using a pick is the only option in the end.

I have a Carvin B1000, which has a preamp valve. I like it Has 6 band eq, so is tonally very versatile. They're not common, but worth trying one if you can. I swapped the ECC83 valve for a slightly lower gain version, which gives a more finessed transition when moving between clean and valvey sounds.

I would just suggest that you don't buy anything sight unseen or unheard on the basis of recommendation alone. All the kit suggested above is good. Whether it will suit you is another matter. You wouldn't buy a car without driving it. It may be inconvenient/tedious to traipse around trying things out, but it's the only way to guarantee you won't be disappointed.

Neutrik make a fat-bodied jack plug which will accept heavier speaker cables.

Perhaps, but it doesn't hurt. As I have a fairly powerful PA, I just use offcuts of 2.5mm cable to make my bass rig cables. 4mm is overkill, I agree.

No, but have a look at this (only a few mins) - How to wire Neutrik SpeakON cables - YouTube - which shows what to do

Speakon cables are simple to make. Just make sure you buy genuine Neutrik Speakons (cheap copies don't always fit well and can jam) and decent cable - Van Damme or similar. Get at least 2.5mm for all but low power applications. No soldering required. Just cut the cable strip to the correct length (the Speakon packet has a diagram to guide you) and screw them in. Takes 5 mins tops. You only need two pole 99% of the time.