Here I attempt to pre-empt your questions with facetious answers that I have made up

What if it’s not broken but just sounds crap?

Glad to help. Components drift in value on old amps – sometimes this makes them sound nicer, sometimes not. Old AC30s can lose all their bottom end this way – nothing broken but horrible nasal tone with no warmth. This can be put right, and it doesn’t always mean replacing everything in sight at huge cost. It can however often mean it’s best to do a ‘cap job’ – replacing all the electrolytic capacitors in the amp – as these are the components most likely to drift and affect tone, and if one’s gone the others will soon follow.

Can I get more distortion/crunch?

Oh yes. I can’t turn your AC15 into a Mesa without a total rebuild, but you can generally find a bit more gain than manufacturers build in quite readily. The limiting factor in going for more gain and crunch is usually oscillation (a kind of internal feedback which high-gain circuits are prone to – symptoms include motorboat chugging, crackling sounds following notes, momentary volume dropout after you hit a big chord as well as various squeals and howls). Manufacturers build in a safety factor to avoid such problems – which we can nibble into a bit, or maybe a lot, depends…

Er, mate, what it is, I like bought this amp on Ebay and, er…?

…and the wife said what was actually rather a hurtful thing when you unwrapped the parcel, about it matching all the other bits of old crap that don’t work that you’ve been filling the house with. The ‘investment’ argument doesn’t seem to wash with her, and actually, it really doesn’t work, does it, and that’s going to be a little bit hard to explain. But that’s ok! I can fix it! …Probably! Really, buying a pre-printed circuit valve amp that’s bust isn’t really all that stupid (though some of the prices are). Worst case scenario – one or another of the transformers burned up, and it took some stuff with it, including whatever shorted out and burned it up in the first place. Then someone put it in a skip, then someone else took it out and put it in his shed in a sack with a load of other stuff he got out of skips (he wasn’t married, obviously). Twenty years go by, time takes its toll, and the executor of his will finds it in the shed and puts it on Ebay with all his other bits and pieces, and is amazed to find it’s worth only slightly less than a house. (From what I’ve seen this is a very typical Ebay amp sale scenario.) But it’s still not a tragedy if your bidding finger ran away with you a bit. Even if absolutely everything I’ve just mentioned has happened to it, it might cost you, say, 300 quid or so for me to fix it – a lot less to raise your average dead amp up from the dead. Now then, to buy a new amp that good’s going to cost you a grand, and a fixed-up secondhand one probably not much less… so, within limits, and after doing your sums, go for it. If you’re transfixed by something bust on the ‘bay, drop me an email and I’ll tell you what I can about it. Good old Brit valve amps to splash out on even if they’re bust include Burman (any Burman), White, some early Carlsbros especially the old 50 Top and 100 Top, and Roost, as well as the more well-known and thus expensive types.

Do you fix solid state amps?

All the time! Guitar tranny amps generally can be sorted out economically. Older transistor equipment is often well-built and also readily fixable, though if it is pre-1980s many of the parts will likely need replacing, and some will be obsolete and unobtainable. Many old or new tranny amp problems are peripheral – switches, fuses, pots – and things like that can be sorted quite economically. If it’s a high-wattage amp – like modern stereo power amps and many modern bass heads over 200 watts – and there’s no output or the protection light is on, then the chances are we have shorted output devices, the product of overheating or shorting out the speaker connections. There may well be some collateral damage to go with it. This sort of job can easily cost over £200 I’m afraid. Stereo power amps of the sort used by discos etc are generally (a) burned right out if they have blown a fuse and thus dear to fix, (b) cheap to replace, and (c) well, you work out why I rarely end up taking these jobs on. We just need to avoid situations where you end up giving me more than it would have cost to buy a new amp. For the time being I am not taking in transistor hi-fi equipment, sorry. Valve hifi, no problem.

Don’t you like hifi then?

Well I try not to get too emotionally attached. As I said, at the moment I’m not taking in any more transistor hi-fi gear, and I am cautious about solid state stereo power amps. Guitar transistor gear, no problem. What it is, hifi equipment often has faults that are multiple and complex to trace, can have obsolete and hard-to-find parts, and often has manufacturers that don’t help with spares, repairs or circuit diagrams. As I have a no-fix-no-fee rule, don’t do the expensive (to you) ‘estimates’ thing, and keep prices as low as possible, the lack of support from makers can mean a day or two’s work to discover that a repair is uneconomical or impossible, which I cannot (or will not) charge for. Sorry about this, it does go against the grain a bit but transistor hifi manufacturers are not repair-oriented on the whole and I have given in to the restrictive practices their accountants impose. I don’t really have the time to build the necessary relationships with hifi manufacturers against the grain – though others do, or have enough experience to be able to do without. I note that JB Amp Repair in Poole, which seems to be a decent setup, are happy to do hifi :). My world is all about making music. However, if you have waded this far through my rambling prose (bless your heart), and you can obtain and supply me with a full circuit diagram for your hifi amplifier, valve or solid state, then yes I will take it in and try to fix it. You earned it.

Would you like my SEO company to get you higher on Google?

I get a lot of cold calls from search engine optimisation companies. They claim to already know that my website needs their help. Clearly they have done zero research, and if I haven’t already hung up I ask them to do what they should have done already (if they weren’t nuisance callers trying to con me out of money), and google ‘amp repair’… and then tell me what improvements they propose to make, if they can think of any. So if by some strange turn of fortune entirely new to my experience you actually represent a reputable SEO company rather than a bunch of cold calling scammers, why not try googling ‘amp repair’ before contacting me? Then maybe I will be happy to receive your call. Otherwise, please could you do one? Because the world needs scamming nuisance callers even less than a picnic needs wasps.

Steve mate, how do you get your website so high on Google?

Now that’s a better attitude. Well what I did was I put the site together myself on WordPress, which is brilliant and quite easy once you get your head round it, and I put as much useful information on it as I could. Some nice customers mentioned me on forums etc and I put a lot of links up myself, which generated some return links. So between actually offering useful information rather than sales bs, giving people something interesting (I hope) to read, and generating some incoming links, hey presto I am high on Google, together with one or two other people in the same line who have similarly informative sites. No big secret. I admit that it helps that there are not that many amp repairers with websites out there.

Can you modify my amp for harp so it sounds good and doesn’t feed back? Or build me a harp amp?

Yes I can. I’m a blues harp player myself and I build my own gear. So, I could build you one from scratch. For sound economical reasons, however, most people prefer me to modify an existing amp. Many old valve PA amps are good for harp – they were built to amplify exactly the same high-impedance, high-output microphones that harp players love to use. Some modern guitar amps are good for harp. The Fender Blues Junior, Blues Deluxe, Blues Deville and Bassman Reissue are particular favourites of mine for adaptation, and the little Vox AC4 makes a lovely harp amp with a few mods. They need gain reduction, often a flatter EQ curve with no mid scoop, and some of the highs limited. What I generally do is a while-you-wait job, so you can try it out and we can get things just right. It usually takes 2-3 hours, which costs £60-£90 for labour, plus £20 each for any NOS lower gain preamp valves we swap in from my stock (£25 for 12AY7). See my Blues Junior page for a standard set of mods to this potentially very useful harp amp.

Can you give it more top-end bite? Or tighten the bass? Or…

Yes indeedy. This sort of tonal tweaking is quite easy to do and doesn’t stretch the parameters of the amp’s reliability or stability as much as going for gain does. What I’m not so comfortable with is – ‘can you make it more like on this record’, or ‘…kind of browner’, or ‘…more musical’, or ‘…less creamy’. I mean don’t be afraid to ask about tonal changes, and if I can translate your wishes into electronics I will, but in the end I’m a repairman not a guru. Lots of mods are possible. More gain can often be found. Extra gain stages can be inserted. It’s easier to do this sort of thing with old point-to-point amps than with circuit boards, but even on boards some things can be changed. We need to talk this kind of thing over pretty thoroughly though, so we both know what I’m going to do.

Do you buy/sell amps?

It’s been known. But no, not really – it’s a funny old market – everybody seems to want an immense amount of cash for their old amp – and I’m never sure who’s actually going to want to pay it. Not me, usually. I don’t keep a stock, nor do I have a wonderful treasure-house of amps I bought for a fiver in the early seventies all piled up in the garage and secured with a padlock out of a christmas cracker. Sorry, burglars.

Can you make my Fender 112 sound like a Marshall?

Yeah, for about the cost of a Marshall. It might be better to say that I could move a Fender a little towards a Marshall by pepping up the drive whilst preserving the top-end. I can make Marshalls more like Fenders too. And there’s usually more gain to be found. Oh there’s no end to it.

My silverface Champ is a bit boring…

There are a few things I like to do to these basically nice old amps to liven them up and make them get out more. One is to fit a reissue Jensen P8R 4 ohm speaker. They are made for the amp and sound great in there. The other is to tune the negative feedback circuit to bring up the gain and liveliness. These amps can be made to sound absolutely wonderful – a chimey, clean sound that leaps off your fingers, and past 7 or 8 a nice fat crunch. The speaker costs about 75 quid, but the specific work that makes all the difference is only £30. (This price doesn’t include any other faults / problems you may be experiencing!)

Hello Steve.

Hi there.

Do you offer amp valuations?

Well, that would be a moneyspinner… but why not do what I’d do and have a look on Ebay? (that’s enough about Ebay – Ed.)

Are some components better than others?

Well they certainly vary. Capacitors cause a lot of debate in this area. It’s quite subjective, but I like to use Sprague Orange Drops. I think I can hear the difference and so will you, especially in high gain amps with plenty of stages for the signal to pass through. Otherwise I use good quality modern mainstream components. Filter caps, for instance. Older amps often have those big cylindrical can caps sticking up from the chassis, and they do get tired. Modern direct replacements are available and I used to fit them, until I had a few go wrong and gave the matter some thought. These large can-type replacements are manufactured in very small numbers for the guitar amp repair market only. Equivalent values are available in smaller modern caps that are manufactured in their millions for all sorts of circuits and mass-produced products. Which are likely to have better design and quality control, the ones that were just made for guys like me, or the ones they make for Sony? So nowadays I fit the modern smaller filter caps on a little tagboard inside the chassis, leaving the old ones in situ for appearance’s sake. Much more reliable. (For more on this, see below for the old valves, speakers issue and go to the blog page)

Can I damage my amp if I don’t match the output impedance with the speaker impedance?

Certainly you can. With transistor amps you generally have a free choice of speaker impedance so long as it’s above 4 ohms. Some will go down to 2 ohms. Even so, shorting out the speaker connections on a tranny amp is very likely to cause major damage. The real danger to valve amps is too high a speaker impedance, not, as most people think, too low. Plugging a 4 ohm output into a 16 ohm speaker is more dangerous than plugging a 16 ohm output into a 4 ohm speaker. So yes, always try to match up output and speaker ohms with valve amps. Having said that, you can get away with a one-step difference, say 8 into 4.

Can I come round and watch you fix it?

While-you-wait is possible if we can find a convenient time. At busy periods (and I have a lot of those), I will have to ask you to leave it with me.

Can you hear that funny noise?

What, kind of a hummy whistley noise? That’s the Russians again, trying to fry our brains. Oh, I see, from your amp. I am patient and understanding about this sort of thing. I may well not be able to hear your funny noise, but I will as a first principle take your word for it and, if it seems realistic to do so, try to do something about it. On the other hand, if I say there’s not much point me fiddling around it’s not that I think you’re imagining things, I’m just trying to save you money.

Do you accept credit cards?

Sorry, I don’t. Cheques… well, you understand… Payment in cash on collection makes sense for me, so I make that my formal ‘terms of business’.

Blimey, that’s expensive!

Valve amps aren’t cheap to build, buy or service – but there’ll be no nasty surprises if I can help it – I’ll always give you a warning to avoid getting you into a money-pit situation. I believe I offer good value compared to others in terms of my hourly rate (and I do work fast). I will be decent and sensible and not get you into uneconomical repair costs when you’d rather have given it up and bought a new amp. Don’t be afraid of asking me about costs, we’re all on budget these days.

Will you fit firecracker Chinese valves if I ask you…

Whatever. Reliable valves are available new, at reasonable prices. I’m not xenophobic. Chinese valves get better all the time.

Do you guarantee your work?

I guarantee that: What I’ve charged you for is what I’ve done, I use reliable parts and that I do things properly The bits I’ve fixed won’t come unfixed because I didn’t fix them properly I didn’t unfix anything else while I was fixing it If I do fail you in any of these ways I will put it right for nothing if you bring the amp back to me. I can’t guarantee that something different won’t go wrong tomorrow – old amps are like that – but if you ask for a service I will, in addition, pick up anything that looks close to its sell-by date and let you know. Basically think of it as like the relationship you have with a good garage who look after your car.

Aren’t old valves better?

I don’t especially recommend ‘NOS’ (‘new old stock’ or ancient but unused) valves, unless you’re interested in collecting them or seeing how they sound for the fun of it. On the other hand modern production valves have a tendency to unreliability in patches, and there are some that I avoid, as the last thing I need are amps coming back to me because a valve popped after a few hours’ use. When valves were mass-produced in their millions it is likely that high plant investments would have been possible, and so the quality might well have been better. Mullards do seem to go on forever.

Which valves sound best? Which ones should I buy? Whose reviews should I trust?

I put some of what I know on my blog page. I wouldn’t glorify it by calling it a review as thanks to GUITARISTS my ears aint what they used to be, but then at least you won’t have to read about ‘detailed soundstages’ etc etc. Most reviews on the web are honest but biased, ie not a lot of use to you. I’m not biased but then I can’t usually tell the difference between types of valve anyway so what do i know? I would recommend buying valves stamped by the manufacturer, simply because it cuts out the middleman. There aren’t that many factories in the world. Here are the ones I know about: JJ – the old Tesla factory, in the Czech Republic. Good name for quality; I have had some reliability issues with their EL84s. Sovtek – the old soviet Reflektor factory, now owned by Electro-Harmonix. they churn out plenty of Sovtek and EH labelled valves, and are also responsible for the current rash of ‘reissues’ – labelled Mullard, Tungsol etc. They are also ‘reissuing’ Svetlana valves (S-logo not flying C) but are not now allowed to sell them over here, no doubt because of Svetlana – still making valves inSt Petersburg but a little bit hard to get due to lack of distributors. Shuguang – in China. They make lots of valves and the quality seem to be good now.

Do you supply valves?

I keep small stocks of the common types to use in repairs or revalves – stocking my idea of the best current-production lines available. I have a flat charge of £10 per preamp valve, £15 for the common power valves and rectifiers. If a valve I have fitted fails on you I will replace it free. I will sell valves to you, matched if you like, at these prices if you want. If you’d rather plug your own in that’s fine. You can give valves to me to fit/bias if you like. If you have some old valves hanging around I can test and match them up for you easy. Mt stock will be the best valves I can get hold of at reasonable prices. Sometimes JJ, sometimes Sovtek, sometimes something else. I often get in a stock of NOS Russian 5881/6L6 and EL84 types, as these are very reliable indeed, and tough too. Sometimes I use Chinese valves, but always with an eye to quality and reliability. I like the Chinese ECC83/12AX7, good sound and reliability, sound nice in Marshalls. Where I can pick up good NOS valves I do, and sometimes I wil;l have to charge an extra fiver or so for something special I have got a stock of. For instance I had some lovely Mullard 12AT7s recently that I could sell at £15, so I assumed my customers would prefer them to Chinese at £10.

Do I need matched pairs of power valves?

No you don’t, is the simple answer, unless your driver circuits and (above all) output transformer are balanced too. Which they hardly ever are. Balanced valves give less hum. End of list of benefits given by matched pairs of output valves in guitar amps. I do try to balance valves IN THE AMP while biasing it up – and if you give me any extra valves you have hanging around I’ll try to balance up the currents for maximum efficiency, if that’s what you want. I wish I could come up with an idea like balanced pairs of valves, I’d make a fortune. (For more on biasing, see my blog page…)

Yes but I’m a sucker, ok? Can you match valves?

Yes. I have a good tester and can match up pairs for you from a batch, if you’re the sort of person who can afford a batch of new valves. If you have some old valves you’re not sure about, leave them with me when you leave your amp and I’ll check them out. I usually test valves in any amp that comes in and I will try to get some kind of balance going in your amp.

I bought NOS EL84s for my Laney VC30 but when I plugged them in they went pop. Wassup?

John from Champ Electronics in Nottingham (see Links) reminded me of this one. The sockets in the VC30 are wired up to accept only one type of EL84. They use a pin that has no connection on some valves as part of the circuit – however other EL84s do have a connection there – and pop they go when you plug them in. Not too hard to rewire the sockets if you have this problem. The advice is to get this job done before plugging in any new power valves except those Laney supply. While we’re on the subject, John pointed out another issue on a VC30 he had in. He’d sorted the wiring thing, but still found that one of the power valves glowed red on the plates however many times he checked the bias. Then he noticed it was very close to the speaker magnet. The magnetic field was helping the current flow, overheating the valve. Well spotted John. Tricky little amps, VC30s.

Is biasing necessary?

Aha, the issue of issues. It’s wise to have it done when you change power valves, yes, though not always an urgent necessity – depends on the situation. Usually I bias for power and clarity. But it’s your choice. If you want me to go for less volume and a browner, distorted sound, let me know – some amps suit this approach better than others. Timescale? It’s not going to take me long to adjust your bias in most cases. See blog for more on this controversial issue.

What are the best speakers? Are old speakers better? What replacement speakers do you fit? Aren’t old speakers better?

I’m a bit heterodox on this. There is an immense confusion of voodoo out there about ‘vintage’ speakers. All the disagreements are a sure sign to me that there’s really not much difference anyway… So, unless you specify otherwise, I’ll replace clapped out speakers with a decent modern ceramic. Good new ceramics are cheap, sound good and handle ‘loud’ with aplomb. Y’see, for me the best thing about valves is the lovely mix of harmonics that makes a guitar really chime. Valves make distortion musical. So, I like a speaker that doesn’t get in the way of that. But of course I’ll fit anything you want fitted. If you like, I’ll offer a view on what you’ve already got and how we might get it to sound more like you want. The speaker I most frequently recommend is the Eminence Deltalite. This is a neodymium speaker available in 10,12 and 15 inch versions, cast frame, power handling 250 watts plus. No chance of ‘cone breakup’ etc with these! But what they do offer is clarity, good sound projection and mud-free bass. Very close in character to the old Electrovoice speakers that Fender and Mesa used to fit. And light! If you have a multi-speaker setup, try mixing speakers and speaker types. This almost always sounds better for guitar than two of the same type. It adds complexity, naturally. So if you thought you might buy two new alnicos in your Vibrolux 2×10, buy one instead!