The Philosophy of Shouting

Anybody misguided enough to follow these blogs, might find themselves a little bemused by the title. Forgive me for not running out to jump off a bridge in shame, but there really aren’t enough of you to warrant the effort of burying my hamster. That’s if I had one, and if it were dead.   

“Am I going to fix my amp by shouting at it?”  ”Is it going to take any notice of me?”  ”Will it shout back?” All these things and no doubt hundreds more will flood your mind. Unless you’ve just got up, in which case there will be three. “Where did I leave the toilet?” “When did I last use the toilet?” and “Is it too late to bother to use the toilet?”

Anyway, onward and upward. If I knew what I was doing (re- internet-things) I am told (mostly by people I’ve never seen in my life.) (And probably wouldn’t want to even if I had. If you take my point.) that I should put a reference to the TITLE, VERY EARLY IN THE BLOG. (No I haven’t accidentally put the ‘caps lock’ on; that was meant to be SHOUTED.)  And then there are allsorts of folks telling me about H1 and H2 and H3, none of which convey anything at all. I know a bit about the H-bomb, and I don’t like that at all, so I imagine that I don’t like the other ‘H’s’ either.

This is where we get to the PHILOSOPHY OF SHOUTING. (See, I can do internet things!) The point I make is this. If I know about SEARCH ENGINE OPTIMISATION, and VERTICAL SEARCHES, and HORIZONTAL SEARCHES (you lay down for them) and SEAWARD-SKYWARD SEARCHES (I just made them up), then, without knowing anything else at all (in other words being a vacuous old git; so what’s new?) I could disseminate this absolute dearth of brain activity to millions. And much good might it do them.

On the other hand (that’s the one I have my jam sandwich in) if I happened to be the possessor of the Infinite Clue, the answer to Life, the Universe, and Everything; and put it on my blog, the chances are that my dog might get a read of it. Eventually.  That’s if my dog could read and if I had one.

I don’t actually see much difference between knowing the in’s and out’s of the processes of promotion on the internet, and SHOUTING.  How can I put my point more succinctly?

Let’s say we have two perfectly reasonable human beings sat next to each other on their little computers. That might be a problem depending on the day. Monday is a bad day to look for these two perfectly reasonable human beings, as they are outnumbered by an astronomic number of unreasonable ones. Friday would be a better day. Let that go. We will, however unlikely, have found two perfectly reasonable human beings to sit in front of two perfectly reasonable computers.

The first one (who we will call Dufrace Moribund, for no good reason actually) writes on his computer:

               I AM VERY GOOD SO PAY ME A LOT OF MONEY. He then gets all his tags right, employs SEO websters and all the other stuff, and gets paid millions per click. Or whatever.)

On the other hand (at this time free, because I’ve been eating my jam sandwich) Fountainburg Slurry has just invented a matter tranporter that can be built from a shoebox and two bits of elastic, and is happy to give it away on the Internet. Except he only knows about matter transporters you can knock up from a shoebox, and nothing about SEO’s etc…etc… 

Centuries later, this is discovered by the remains of the human race (which is a rock on Planet Grunt) the rest of it having been decimated by ravages of global warming that everybody could have avoided by knocking up their own shoe-box matter transporter. Instead they (we) all fried shouting……

                                     “I AM GOOD SO PAY ME A LOT OF MONEY”. If you see what I mean.

Marshall, Fender, Mesa, Ampeg.

So your amp was once a Marshall, or a Fender, or a Mesa, or an Ampeg. But right now, you’re standing on this stage, in front of a lot of people, who want to be amused. And your amp (whatever it is, in this situation, it’s going to be a ‘Bastard’,) doesn’t work. What next? A variety of entertaining ideas spring to mind.

         1) You are dismembered in nasty ways by an audience who finds a load of folks on a stage not doing anything at all, disappointing. 

         2) Thoughts of hammers, axes and (admittedly a little extreme) chainsaws, mincing your nice amp into a sackful of bits the size of an oxo cube, rush unbidden through your steaming brain.

            3) Possibly worse than those improbable alternatives, you reach for a screwdriver.

            4) In order of prospective danger, figuring out where you might stick that screwdriver ranks high on the list of ‘Dont’s’

            So might we find some useful alternative to panicking like a headless chicken? Shouting at the drummer is usually a good start; just to ease the tension, you understand. After that, here’s few things that might at least feel positive.

Let’s concentrate on the amp.  Concentrating on anything at all at least alleviates the ‘Black Hole’ syndrome. That’s where you wish that one would turn up and spirit you away to another galaxy.

Does it light up? No? Is it switched on? Don’t pull your hair out; it happens.

Is the wall socket switched on? Is the multi-block plugged in? Is the IEC socket (the kettle plug) fully plugged in? That’s an easy one to miss.

The IEC mains inlet in the amp might be fused. If so it will have a little slot-in plastic section moulded into the IEC socket. You can get to this without opening anything. 

UNPLUG IT!!!!!!!!!!! Then you get a small screwdriver (I’ve done it with a fork, a toothpick, a cocktail stick) and lift the slot-in section out. Inside there is usually two fuses. One at the bottom which is the operative one, and the one nearest the surface plastic that is a spare. They’re usually glass, 20mm things, and if it’s blown you’ll see that the wire inside is either broken or non-existent. Then you take that one out, and put the other in that slot. Hey presto! Done!

No? Oh dear. Check the fuse in the plug. You can’t see whether these are blown or not, so it’s either swop it, or put a meter on the ohms scale, and check it reads zero. Failing that showing anything, borrow somebody’s lead.

Beyond that, you’re struggling. There may be two more fuses in the back of the amp, usually of the same (20mm) type that we found in the mains socket but installed in screw-in fittings, usually not far from the IEC socket.  Either of these blown could be due to a surge at switch on, or you could have big problems. If you have spare give it a go.

On switching on valve amps:- Always use mains first and then standby after. Give it as long as practical to warm up before switching on the standby. Otherwise surges can occur as the bias voltage builds up. This is especially true with solid state rectifier design. Leave it as long as you can before you move a valve amp that is hot. The elements within the valves distort slightly when hot, and can give you faults (particularly heater-grid-cathode shorts which are very bad news on power valves, and unpleasant on preamp valves).

What if everything seems ok but it just doesn’t sound? Is there anything from the speaker if you wind the master volume up? No? Have a look at the spade connectors on the back of the speakers. Make sure the amp is off, if they’ve drifted loose slot them on again and check they’re a tight fit. If all looks ok, concentrate on the front of the amp, as there’s nothing more you can do at the back.

A lot of modern amps have a relay that switches off the input stages of the amp. This (I think) is because modern amps tend to be noisy because of the high gain stages, and by effectively disabling the input stage it makes the amp tick over at the same sort of noise levels as an old Fender Twin. Which were deathly quiet. How does that help?

Well, if the switching at the back of the input sockets is bad, you’re amp won’t work. Blast some switch cleaner in there (if you have any) and then shove the jack in and out. If no switch cleaner, do the jack thing anyway. DON’T USE WD40. It has a sticky oil base that although fine on electrical things, is not good on electronics.

Still nothing? Use the same trick on FX loop send/returns. You could also try a patch lead in them, instead of your pedal system. A bad lead/ dud pedal could easily be the cause.

What about buzzes? Loud hum/buzz can be as bad as your amp not working at all. Check the daft things like instrument leads. Is it affected by control settings? Spring line reverbs can make nasty noises. If you turn the reverb down and it goes away, get to the phono leads that plug into the amp and pull them out then plug them back in. Contact cleaner also, if you have any. You can’t always get to the amp outs to the reverb, they’re sometimes hard wired. But you can get to the reverb tray which is often screwed to the inside of the amp cab (Marshall, Mesa, etc) or in a black plastic case in the bottom of the amp. Same thing as the other phonos. Otherwise just switch it off. 

Last of all, and this is a bit extreme; a very loud buzz that won’t go away if you turn all the controls off can be a soft output valve (red plate is the modern version of the terminology). Have a quick look in the back for a glowing red valve (that’s one of the power valves. Big; EL34 or 6L6 or 5881; or maybe EL84 or 6V6 if it’s a Vox or a nice little Ampeg. Anyway, if there is a soft output valve in there, it will be GLOWING. SWITCH IT OFF.

There’s not much you can do. But if you have a hundred watt amp (ish) you’ll have four in the back. If you take out the two inner valves (or the two outers, depending on where the red valve is) you’ll have a fifty watt amp, that works; rather than a hundred watt one that doesn’t. This won’t bother your amp, but it’s best to get it sorted out at your earliest opportunity.

You can’t do that trick with an old AC30. The biasing arrangement is quite different.

One other possibility on the buzz/hum thing is a heater/cathode short on a preamp valve. Unless you have somebody pretty familiar with taking the back off an amp, it’s probably best left alone. If you have a spare ECC83?

Check if the hum can be turned off at the master volume. If yes, the fault is in the first stages of the amp. The preamp valves are usually furthest away from the power valves. So progressively swop those for the good ECC83 you have.

Watch how you replace them. They’re a nine pin base with a locating gap. The gap is usually marked in some way on the chassis of the amp (might be a little tag or a v-shaped nick). Make sure any screening cans go back over the valve. 

If the master volume doesn’t affect the hum, the fault could be on the phase-splitter. This will be the nearest small valve to the output valves. It’s usually an ECC83 (12AX7) but it might be an ECC82 (12AU7) or even ECC81 (12AT7). Either way, your ECC83 won’t hurt anything in there, but you might find a difference in overall gain and it might distort. All this you might just get away with by adjusting  the master.

Sounds like a lot of messing about, but the first bits you could do in less than ten minutes, and the whole lot in maybe a half hour.  

If all else fails there’s always the rear exit. Time for tea.

Boots Morgan and his Horse

Having revealed the inner truths of the Universe (Not this one. None of this one makes any sense.) in my silly piece on marketing my book, we shall now soar amongst the more remote (and less preposessing) extremes of my sock drawer in search of the meaning of something.

This is a plug (sorry; marketing stratosphere; or something;) for another of my books on Amazon, as if one weren’t far too many. I’ll get back to something useful when I’ve got this off my chest.

It’s a sort of cowboy/western/humour/whodunnit/lookingafteryourdonkeymanual/investigations into paranormal transmigrations/DIYlogcabinbuilding/how- to- dream- up- tags- that-appeal- to-the- majority- of- the- population- of- the- solar-system- excluding- the- Earth. I think that more or less covers it.

Oh, yes; and all the ‘Tols’ like it. Tolkien, Tolstoy, Tolpuddle martyrs, Birmingham Tollgate. I think it’s the big words that do it. I got ‘Wednesday’ in it, somewhere, and you don’t get much bigger than that.

You could, at the furthest reaches of the imagination, even read a bit of it. For nothing. Here’s a review of it. Nobody has actually reviewed it, because nobody has actually read it. All that fascinating information about how to grow your toenails fast, just wasting away.

Here’s an unbiased review of it, then, by me.

I like it, because it makes me laugh. It’s also very erudite because it has big words in it, like Wednesday. 

Anybody who’s just come out with a word as big as Wednesday, deserves a cup of tea.

WEM Teiscord Organ

The little Teiscord is still favoured in some surf music circles, even though it dates back to the Ark. Well, nearly. Early ’60′s at a guess. This one is the fourth I’ve seen in a year or so, and the technology is utterly different to current keyboard offerings. The fault in this case was that there were frying noises at the output, and the Bb range of keys had lost the low octave.

The condition of this instrument was stunning. It seemed unlikely it had been used much, and certainly not ever gigged.

However, time had taken it’s toll, and the faults described above rendered it unuseable.

The major (practical) difference between these keyboards and the latest from Yamaha, Technics, etc. is that they are eminently fixable.

A fault on a current keyboard will generally involve unplugging a monumental pcb, which will constitute most of the insides, and plugging in a new one. Easy job once you’ve unscrewed half of B and Q’s stock of self-tappers. But the price of the component itself is unlikely to be cheap.

This organ is full of transistors, which are now obsolete and not easy to get hold of. 2sc536 or 2sc537 or 2sc538 to be precise. There are still plenty of devices that will substitute for these however. I used BC183, whch involved swapping the pins around. I’m sure there will be other possibilities.

The box on the bottom left of the pic, houses the generator/divider pcb’s. Twelve in all, one for each note. Above that is the pcb that the tabs are mounted on. The little marked off bit at the left of it has three transistors on it. Two of them work together to form the oscillator that supplies the vibrato effect, and the third is the preamp, the output of which is applied to the master volume pot. If you’re thinking about taking this to bits, make sure that the insulators under the mounting screws go back where you found them, or it can short signal paths etc., to ground.

This is a closer view of the generators; you can see that each one is marked on the retaining bracket. C,D,E etc. 

The way the note generation is achieved is by a circuit called a multivibrator. It uses two transistors and produces a square wave, which is a complex wave having a lot of  harmonics that can be filtered to produce different sounds. There is also a preset pot to adjust the tuning of each note, but, unless you’re very patient or well versed in the art of tuning in equal temperament they’re best left alone if the tuning is tolerable. 

This is what a generator pcb looks like. The two transistors next to the big green capacitors on the right generate the tone, and after that each pair of transistors, moving to the left, divide this first frequency progressively through five octaves, using a circuit similar to the one that does the generation.

It’s very rare to have bass octaves present and top octaves not, and if this is the case, it’s almost certainly contact problems which are situated under the keyboard. A good squirt with contact ceaner (NOT WD40) will often sort this out. If the lower octaves disappear, it will likely be one pair of the divider transistors. Count them from the right, down to the faulty octave.

One other thing; there is a schematic stuck to the bottom of the case. What a great piece of common sense!

Time for tea.

Fender Hot Rod Deluxe

Fender Hot Rod Delux. This was a rush job, and I thought  it was going to be a brain crusher. Not that there’s much left in there to be crushed. A decent-sized garlic press would be ample.

The sympton was that the channel switching didn’t work, and the LED that shows the condition of the overdrive channel (drive/more drive) didn’t do anything.

There were a few possibilities. I have to apologise for the absence of any pics. I am camera-less at the moment.

When the back is off the amp, you see the flat face of the component side of a pcb, that takes up most of the chassis. There’s another one across the bottom that houses the valve bases. In the top left corner of the main pcb (near the preamp output socket)  is a wirewound ceramic resistor. It’s a white-ish oblong thing, and it’s marked R97. This is a cause of problems. It’s function is to supply an ac voltage/current to the channel switching relays, etc., and it’s designed to run hot. Underneath that at the back of the pcb, are the tracks and soldered joints that carry the 35 volt ac from the transformer.

These are no problem in the first place, but after a year or two’s heating up and cooling, the solderjoints dryout and the constant vibration from the weight of the resistor itself, cracks the tracks. If you’re unlucky it might have blown the chip that drives the relays and LEDs. This one had. It’s a 4558 chip, but a TL 072 is fine and easier to get hold of.

Fixing tracks under a hot resistor has to be done in a particular way, or it will come up with exactly the same fault, in the not too distant future; as this one had, it having been repaired at some time previously.

Solder bridges across cracks in tracks are not a good idea. You need a piece of copper wire of a suitable size and diameter, and that needs soldering across the track break to a centimetre or so either side the break. If it’s under a hot component, it’s best to step the component away from the pcb by a few milimetres and use a higher melting point solder, like, say, solder with a silver content.  

Any job that involves removing the pcb is fraught with trouble. At the bottom of the chassis is the flat pcb that houses the valvebases, mentioned earlier. A number of flat ribbon cables connect it, and they are of hard drawn copper, and they don’t like to flex much. Beware if they are moved around much because they’re rigid and the cores tend to break off flush with the pcb surface.

You really have to be very handy inside an amp to attempt something like this. It’s very easy to finish up with a lot more trouble than you started with.

Time for tea.

And what about Einstein, then?

I figured if I constructed a post so devoid of any sense and reason, I ‘d be able to single out the robotic/semihumanoid at a stroke. For anything to post a comment that starts “truely, the philosophy of this site is such that I was moved to inculcate, nay opinionate, my devout respect for the ….blah, blah….” having just read such a total toadful of bollocks as I am about to insult this screen with, would be a dead giveaway, and I could metaphorically slit its throat with little more  reflection than a slight belch of satisfaction.

Were my name Einstein, I could guarantee that my other name would be Dinglebury. And it would undoubtably be hyphenated. So; Einstein Smithe-Dinglebury. What, you might rightly wonder, has that got to do with anything at all?

This would, at a stroke, and from birth, relegate all my researches in relativistic physics to the shelf marked ‘Music Hall Scripts’  and everybody at the ‘Queen Vic Variety Revue’ would be rolling in the aisles to ‘E=MC squared’ gags. You see? Contrarily, had my name been ‘Bertrand Reactionary’ I would have been guaranteed a seat on every subversive commitee this end of The Wash. Not that there are that many.

With a name like that, I would have been the recipient of vast fortunes from New Labour (that’s the same as Old Labour insofaras no member is even remotely related to anybody who ever did any) just to say “Ya Boo!” to anything that might look like a conservative.

Were I a  ’Tony’ or ‘Anthony’ Something-or-Other, I could start my own political party (called ‘The Tony’s’ of course), in which all members would need to sign a subs card that effectively pays the founder (me) in perpetuity, regardless of whether I’m any good or not. Not unlike buying a box of firelighters that only work in the rain, when you happen to live in the middle of the Sahara. A lot of politics seems to be founded on that principle.

In normal walks of life, the fact you can’t do a job at all, more or less assures that you won’t get to do it for very long. Politics doesn’t seem to work like that. If one finishes up with an Amin or Gadaffi or Hitler, (etc. etc. ) you get somebody who is probably exactly right for some other job, but incompetence is such an inbuilt seam running throughout the profession itself, they stick in there  like shit to a blanket.

I’m just wondering how many robots have stuck with this, on the subject of sticking.

Were there such a name (there’s bound to be somewhere) as Bigsby Syntax I would want it, as it would bestow at least a knighthood on its possessor, and probably an earldom. Or is that Earl Dumb. Oh well, let it pass. I do have a funny hat, which is bound to be a good start should I wish to sink to barristership; hood; whatever. The name to have for that one has to be one of those that looks like ‘Trimblsnout-Jinkinstrop’ and sounds like ‘Penelope Glass-Blower’.

“Robots on the port side, Cap’n”.  “Assemble the crew bosun”.  “Crew assembled, Cap’n”. “Altogether then lads”

“YA BOO!!!!”  Alright, so it’s not great as a piece of scintillating repartee; but I’m not wasting any of my emaciated supply of scintillating repartee on a robot. Time for tea.

Feedback

Interesting word, is ‘feedback’.  Depending on the era we might be fumbling around, it might relate to, say, one of those phone calls from somebody you never heard of in India; or Bratslavaland, or Dingledron, or anywhere; people whose main mission in life is to waste as much of as many people’s time in futile pursuits that are, in the caller’s estimation at any rate, essential.

They want your ‘feedback’. This particular feedback is so essential that they don’t want to pay you anything for it. Some of them will hang up in the hope that you’ll ring back to give this ‘essential feedback’ that doesn’t warrant the cost of their phone call. I have, in the past, asked for forwarding addresses, bank details, etc., to where I may be able to forward an invoice for my time, which, were I a member of the legal profession would run well into four figures for a five minute phone conversation. This invariably results in a ‘click’ from the other end (wherever this ‘other end’ might be).

On another tack, if you happen to be in victualing, hotel, restaurant businesses; feedback is something you don’t want to clear up after a ‘feedback event’.

If, however, (and this is where we get to the point; at last) you happen to be an entertainer, singer, p.a. hire gent, or anybody getting involved in the murky world of amplification, feedback is something that can destroy your ears, your amps, your horns and your audience, all more or less at the same time.

All the afore mentioned folk are very well versed in what it is. This is why it happens.

All feedback phenomena exist as loops, and there are basically only two sorts of the stuff; positive feedback and negative feedback. These loops generally start from the output of an amp or system and are a result of some fraction of this output being returned to the input. There are, actually, many feedback loops within an amplifier (every chip in an amp has a variety of feedback loops in it) but the particular ones in which this post is interesting itself, are the ones which, by one means or another, turn the output signal back to the input, negatively.

To deal with the two different types of feedback for a start.

What does it do? Well, in the case of negative feedback, it has a number of effects. Most of them are associated wth stability. Negative feedback in an amp reduces the overall gain, but extends the frequency bandwidth. As a transistor amp has a lot of gain to spare (compared with a valve amp) the feedback factors tend to be much larger (the fraction of the output fed back is larger). This tends to produce a tight, flat sound, that some might find characterless. Me included. 

A valve amp has other complex factors involved with its overall negative feedback (often referred to as ‘damping factor’ in a valve amp) which are involved with the fact that it has an output transformer; and this has a property called ‘inductance’ which significantly (and less than predictably) affects the overall sound, and this often forms part of the negative feedback loop. The less negative feedback you employ within an amp, the more likely it is that factors such as spurious fields from output transformers, airborne interaction between valves, stray signals along power rails etc., may gang up on you, and produce an unstable amp. As components age, these attributes may become more exaggerated.

So, why bother about an unstable amp? Because it will do pretty much as it pleases without any conferring with you, or worrying about what it is you might be putting into it. It might squeal, wail, sulk, get very hot (all of which is quite adolescent, I suppose); do anything except something useful. No further adolescent quips. But you can make up a few of your own should you feel the need. Negative feedback within an amp sorts all this out.

So what about the other stuff? Positive feedback has only one useful function. Unless you’re on ebay, in which case it can keep you in business.

Positive feedback produces oscillation, which can be the generator for a tone. Or if it’s an LFO (low  frequency oscillator ) it can be the control for your chorus, vibrato, flange etc. etc. effect.

But the real crunch feedback is when your mic jumps around onstage, your horns fly out of their cabinets, the power amps blow fuses, and your pa sytem is converted to a pile of scrap in ten seconds flat. How dare it do that?

It’s called an acoustic feedback loop and the magic number is ‘one’. As soon as the positive feedback factor approaches 1, the feedback becomes ‘self-sustaining’ and will continue for ever. Or until it bursts into flame, or you kick it off a bridge.

The loop is formed by the output of the speaker(s) being picked up by the microphone(s), which feed it back into the amp and that chucks it out to the speakers again. That’s the loop.

A lot of factors affect this loop. How many mics you have, where the speakers are positioned, many acoustic factors of the auditorium, what sort of lift you have on the EQ of your mixer/graphics/, effects can have a big ‘effect’ on it. 

It’s also frequency sensitive. This means that if you have a particular band on your graphic wound up, this will increase the feedback factor on that frequency and feedback at that ‘note’. A lot of antifeedback systems revolve around a circuit called a ‘parametric notch filter’. It senses an approaching feedback condition, figures out the frequency and cuts in the notch filter which takes out that particular frequency without affecting anything else.  Then the system looks for another frequency it can annoy people with.  

Feedback is a vast subject, and this little article has merely scratched the surface; but it all brings tea time, and might do a bit of good somewhere.

Intercontinental

Here’s a small contribution to the vast wash of silliness to which I seem to minimally add on a regular basis. My regular visitors from the robotic quarters of the internet will doubtless split a spot weld seam in their jollity. I know they need the cyber-space, but it would be nice if they brought a shovel with them so I can clear away the bullshit that much quicker.

I did think of doing a sort expose-post of all the dismal flotsam that wallows around in the cesspit of the web. But I’d need pile of robots mile high just to manage the effluent. Ah well; on to more significant matters like picking my toe nails.

This a daft little story from a collection of  daft little stories, the entirety of which is not called ‘Daft Little Stories’. I don’t actually know what it’s called but it’s not called that.

Here it is, if I’ve not lost it. Altogether.

            Geography was never my strong point at school. The situation wasn’t helped as I could never find the classroom. Really though, this has never been big issue because I’ve never been far enough to need to know where I might be at any given time. The corner shop is a day trip out in my book (that’s the book I could never find because it was in the geography room); and I always pack a tent and a primus to go to Tesco just in case.

            With this sort of background it has become obvious that I should write travelogues. Let’s face it, it’s easy to write a travelogue for somewhere you’ve been to. But I haven’t been anywhere, so the World, the Solar System; the Universe, even, is my oyster. Here is a quick spin around the oyster

 

                                                             A Trip Round the In-Continent.

            It’s a big place, is a continent; and far too big when you’re sat next to an incontinent dog, on a sight-seeing trip around India after an evening meal of vindaloo; the continent seems never to know when to stop and the incontinent when to go. Should we wish to assess India in a different light, it’s not nearly big enough to allow the kind of space you’d like to put between yourself and the next seat.

            There’s no doubt it gives a travel writer a distinct edge over the competition if he’s never been anywhere. India to me is full of sacred cows and bullshit; a sort of annex of the Houses of Parliament. Having never seen one, I can give a perfect description of a sacred cow. It’s brown. That’s also my description of just about everything else. I might do Russia next; which will be brown, also.

            Just so that you might not miss the point; the only things I know for certain about India is that it’s very big, definitely brown, and I’ve never been anywhere near it. That goes for everything else as well.

            The train was an ‘Orient Express’ sort of thing, built entirely of walnut and corridors that don’t go anywhere. They had a pile of small Poirot figurines at the blank wall at the end of each corridor. This was evidently proof of something, but I never found out what. The continent stretched out to infinity across the paddy fields (or whatever), to a golden sun-something, depending a lot on whether it was going down or up. Rather like the lift at Debenhams in Sheffield, that could do strange things when you weren’t looking. Thanks to my fellow passenger’s (I christened him Dongo-Pongo), problems, I’d survived a good part of the journey with my head stuck out of the window (thereby acquiring enough dead mosquitoes in my teeth to keep the whole train in mozzie vindaloo for a week) except for the odd times I had to pull it in quick to avoid the bits that fell off the engine at intervals. These kept me on my toes like a butterfly in a blizzard (?) and after a week of this exercise, I had a hyper-fit neck and destitute everything else. Well, I wasn’t going to start anything with Dongo was I? He was twice my height and weight. It was a mystery how he managed to keep his weight as he evacuated his entire internals every five minutes or so.     

            Sepia photographs dating from the heyday of the Rag tend to mask the actuality of the transport of the time, as you can’t see it at all. Rarely is the romantic vision of the Orient Express responsible for depicting a bald guy with a mouthful of flying insects ducking shrapnel.

            The sleeping arrangements were similarly marred. Dongo had the bunk above mine. I slept with an umbrella up. Why I’d actually brought one along in the first place I put down to pessimism. For a continent that only sees a teacupful of rain every fifty years it was bound to pee down when I got there. It always does at Blackpool at any rate. We pulled into the station at Bongawaka, or somewhere, and were besieged by the whole of India in total. I had never realised the extent of the mania for autographs there. I managed to get one of David Beckham and Prince Walter, two sacred cows who had ‘David Beckham’ and ‘Prince Walter’ stamped across their butts.

            We were transported to our hotel on a fleet of wheelbarrows (I think). Mine was ‘David Beckham’ and I got its autograph.  

            The hotel was the epitome of opulence. Silk carpets, gold leaf, fountains; it was just that there was nothing in there I could eat. Dongo was ok; whatever he put in at the front came out of the back within twenty seconds of its disappearance so it didn’t seem to matter much. I ate the rush mats. I ran out of them pretty quick because of Dongo’s problem; with edibility you really have to draw the line somewhere.

            We moved on. I was disappointed that I wasn’t wheeled back to the train on David Beckham; the one I had was Adele; she looked about the same though; rusty handles, square wheels and a flat tyre. Nobody’s perfect.

             The next stage was (we were told by somebody who had plastic tag not unlike Dongo’s), a relatively short jaunt across some open space. Pluto suddenly sprang to mind, but was hurriedly pushed to the back burner. We were going to see a spectacular monument, a stunning piece of history, a never-to-be-forgotten experience. The experience was soon forgotten by me, because I can’t remember how to spell it, so the most memorable experience of that leg of the journey was relegated to unsuccessful attempts to hold onto a bowl of soup in the dining car. As it swept past under my nose to the east, most of it dashed against the window and on its fractured and emaciated return journey it fell to the floor, where Dongo pursued it up and down the isle, swerving and feinting between the diners’ legs while they in turn attempted to hold onto their soup.

            That was about it for India. We were thrown off the train (unfairly, I thought; it wasn’t Dongo’s fault that he converted everything he ate into a laxative), and made the long walk back without any form of navigation aid other than feet. Lucky really; with my expertise in geography a map would have been confusing.

            Dongo and I lived happily ever after that, having found that he liked to eat sticks of chalk and half bricks which alleviated his irritable bowel syndrome in favour of irritating me.

            We might do Eurasia next.

            It’s brown.

I don’t suppose there’s much point now.

                                              The End.

More on the Selmer Triumph Reverb

This another quicky, mainly on background buzz/hum. It’s directed particularly towards the little Selmer, but most of it applies to valve amp noise in general. This one had two noises going, one was a 50hz hum and the other a 100hz buzz. It’s hard to describe the difference but the buzz is an octave higher and has a kind of ‘rasp’ to it. This one was mostly down to bad smoothing of rectified ac; and the usual cause of this is either dried out reservoir (smoothing) electrolytic caps, or the same thing having poor grounds. The grounds on earlier caps are often via clips to the chassis, which are fine when new, but the aluminium case oxidises in time. There is often a solder tag on the case, so you can hard wire a ground and sort that out.

 There are also likely to be other electrolytics in there doing a similar job, and are part of a chain called ‘decoupling’. These usually provide the anode voltages to the preamp stages, so noises that can be affected by settings on the volume/channel gain controls,  can often be traced to problems on those decoupling caps.

That more or less deals with the more obvious problems of smoothing buzz.

Hum is sometimes due to poor grounding/screening. In a valve amp the impedances are generally high, which means that wiring inside can pickup from the mains transformer. The hard wiring can be moved around from original routes and moving them around can make big differences. Poor grounds to the chassis of the pots can be a problem, and hard wiring copper rails is a good permanent fix. Again, corrosion to the alloy of the pots makes for bad ground connections.  

The biggest hum contributor is down to a fault called ‘heater-cathode short’, and that means that the heater inside the cathode distorts and touches the cathode, which destroys the bias and  puts 6.3 volts heater supply on the cathode. It can happen on any valve, and is big trouble on the output valves. On any valve it shows up as a VERY BIG HUM.

Last off, cooking foil can be a great hum controller. The flat boards of the cabinet to the back of the preamp sections of many combos can have a piece of cooking foil stuck to them, a screw through it to trap an earth/ground wire, the other end of which is soldered to a ground connection in the preamp. It can make a big difference.

Just a shorty. Time for tea.