The most unreliable amplifier ever….

sweepy

Burman and Musicman were hardly the most reliable of amps, Burman’s  used to regularly cook transformers and Musicman amps, due to high plate voltage used to get butchered by “techs’ and failed regularly 

ICBM

sweepy said:

Burman and Musicman were hardly the most reliable of amps, Burman’s  used to regularly cook transformers and Musicman amps, due to high plate voltage used to get butchered by “techs’ and failed regularly 

I would say MusicMan were very reliable when *not* worked on by “techs” who don’t know what they’re doing - yes, it’s true that the extremely high plate voltages mean that they’re very hard on modern valves (which is becoming a problem as old-production power valves in general are getting hard to find) - but mostly because you cannot bias them in the same way you would a conventional power stage. Other than that, they’re pretty bombproof.

Danny1969

I've been thinking about building my own valve amp for a while. I've got a lot of stuff salvaged from BER'ed amps ....50 watt  power tranny & HRD output tranny ... loads of valves. 

I imagine building something in a sensible linear left to right format. Something in 4 distinct sections that I would find less irritating to work on. 

Power supply section with DC heater rail, valve and silicon bridge rectifiers and diagnostic lights  --  pre amp stage  --- 2 tone stacks for 2 channels - PI and PWR amp section. 

The modern way of just chucking everything except the power valves on one big PCB is just aggravating ... especially when they haven't used headers for offboard connections and you have to unsolder a whole bunch of shit to get the board out. 

borntohang

ICBM said:

Another candidate - the Hiwatt 'High Gain 50'. Modern Chinese-made. They bear no relation to classic Hiwatts at all other than the styling, although they do actually sound good... when they work. Which is intermittently at best.

We still have a few of the HG series around as artist backline, but not for sale. The ones we've kept hold of are mostly from the early UK-assembled run and we fit them with decent tubes before they go out. Suffer from the shared EQ IMO - I can get something decent out of all four channels, but not at the same time.

My main gripe with them is lifting the bloody things. Glad we got rid of the last of the HG100 combos because they were a terrible lug; pretty sure stopping one of them from dropping out of a badly loaded van is why I have no rotation left in my right wrist... The cabs were the best thing in the range by far and are still for sale. I have a stock HG112 and a 212 with upgraded speakers and various fittings which have seen me well over the years.

Flanging_Fred

At the music festival I played at the weekend, a guitarist in one of the other bands was using a Marshall Mode 4 stack. Very brave! It got through the whole (loud) set without going pop! 

Lodious

I had a Vox V125 once. No wonder they got Paul Weller to endorse it...it would have been unlikely to last longer than a 3 minute song.

Supportact

I had a Marshall MG100DFX years ago. The input socket went intermittent within a few days. I took it back to the shop and exchanged it for the MG50DFX (largely due to the fact that I took it on two busses to get back to the shop). That one lasted a while but I never loved it. They were quite cheap and i didn't know much about amps back then. 

ICBM

Flanging_Fred said:

At the music festival I played at the weekend, a guitarist in one of the other bands was using a Marshall Mode 4 stack. Very brave! It got through the whole (loud) set without going pop! 

I'm genuinely amazed that there is one still in operational condition now.

Wazmeister

I actually had two Redplate amps fail 2 gigs running…
in both cases, a Kemper saved my skin (if not my confidence)…

Both were different amps too, and not routine valve failure….

To be fair, it was a known problem on the smaller CDS2s; but I’d still have another in a flash !

DrJazzTap

Marshall TSL. When the reverb stopped working on mine I had no choice but to drive 4 hours to milton Keynes to get it fixed at the factory.
Nobody in the southwest would work on it. One guy said to me "by the time I've even figured out what might be wrong with yours. I could have serviced four fender amps" 

I got the reverb fixed and moved it on. The drive channels sounded lovely. The clean channel was cack though. 

robmac5150

Marshall Vintage Modern. Only amp I ever bought new. Sounded amazing in the shop, but couldn't gig it as it kept failing.

OilCityPickups

By a country mile: Proamplifiers ... I used to sell them in my shop many years ago and they nearly bankrupted me. No sooner did they go out the door than they came back with faults. One I used personally caught fire at a gig ... and one I sold to Dick Taylor of the Pretty Things died a few days after he took it home. I bought in a whole load of the 'Demon' practise amps to sell at Christmas and they started coming back by new year. The company refused to take responsibility and saddled me with refunding and explaining to customers - saying they must have been 'roughly handled' and a million and one other excuses. 
Utter crap! 

Telejester

Peavey Classic 30 ( imo a pile of junk )
Marshall DSL50 & DSL100 heads, both blew their output transformer.....never again

ICBM

Telejester said:

Marshall DSL50 & DSL100 heads, both blew their output transformer.....never again

Out of curiosity, were they going into the same cabinet - a 1960 4x12” with the switching system? Those are notorious for contact problems in the jack switches and PCB joints, going open circuit and blowing OTs.

Not that there aren’t other problems with the amps as well…

The Classic 30 is also Peavey’s worst amp in my opinion.

Danny1969

OilCityPickups said:

By a country mile: Proamplifiers ... I used to sell them in my shop many years ago and they nearly bankrupted me. No sooner did they go out the door than they came back with faults. One I used personally caught fire at a gig ... and one I sold to Dick Taylor of the Pretty Things died a few days after he took it home. I bought in a whole load of the 'Demon' practise amps to sell at Christmas and they started coming back by new year. The company refused to take responsibility and saddled me with refunding and explaining to customers - saying they must have been 'roughly handled' and a million and one other excuses. 
Utter crap! 

I had one of these and it did indeed go wrong. Most of the faults were minor in fairness and caused by the amp trying to be a cheaper kind of Boogie. 
I still have the cab and speaker which I have used as a 1 x 12" cab for hundreds of gigs and it's actually the best sounding 1 x 12 cab I have ever used. 

ICBM

Danny1969 said:

I had one of these and it did indeed go wrong. Most of the faults were minor in fairness and caused by the amp trying to be a cheaper kind of Boogie.

If I remember rightly some of them were a poorly-implemented MusicMan copy, with the same type of very high voltage power supply and cathode drive to the power valves but with nowhere near the quality of components.

"Pro" is a term often used on equipment, it's an abreviation for "professionals wouldn't touch this with a bargepole".

Keefy

OilCityPickups said:

By a country mile: Proamplifiers ... I used to sell them in my shop many years ago and they nearly bankrupted me. No sooner did they go out the door than they came back with faults. One I used personally caught fire at a gig ... and one I sold to Dick Taylor of the Pretty Things died a few days after he took it home. I bought in a whole load of the 'Demon' practise amps to sell at Christmas and they started coming back by new year. The company refused to take responsibility and saddled me with refunding and explaining to customers - saying they must have been 'roughly handled' and a million and one other excuses. 
Utter crap! 

I remember reading a glowing review of the Proamp Demon in Beat Instrumental around 1980 and lusting after one. I never did find one though so it sounds like I had a lucky escape!

OilCityPickups

Danny1969 said:

OilCityPickups said:

By a country mile: Proamplifiers ... I used to sell them in my shop many years ago and they nearly bankrupted me. No sooner did they go out the door than they came back with faults. One I used personally caught fire at a gig ... and one I sold to Dick Taylor of the Pretty Things died a few days after he took it home. I bought in a whole load of the 'Demon' practise amps to sell at Christmas and they started coming back by new year. The company refused to take responsibility and saddled me with refunding and explaining to customers - saying they must have been 'roughly handled' and a million and one other excuses. 
Utter crap! 

I had one of these and it did indeed go wrong. Most of the faults were minor in fairness and caused by the amp trying to be a cheaper kind of Boogie. 
I still have the cab and speaker which I have used as a 1 x 12" cab for hundreds of gigs and it's actually the best sounding 1 x 12 cab I have ever used. 

When they worked they sounded great ... but keeping them working for more than a couple of gigs was impossible. Nasty cheap valve seats ... cheap transformers - suspect soldering. The speakers were good ... at least in the bigger amps.

I see there is a fecked up one for sale on eBay at the moment spares or repair with no speakers in the cab 


.  

Tex Mexico

ICBM said:

ScreamingDave said:

Funny, I’ve had three Marshall DSLs and a TSL over the last 18 years or so and never had any problems. Just the usual valve replacements when it’s gigged and rehearsed hard. Just goes to show, you never can tell ….

You’ve probably been reasonably lucky, but that’s what I meant about proportionate failure rates. If 25% of a particular model fail that would be terrible, but it still means that three-quarters of owners don’t think there’s a problem. To have four of them and not one failure is less likely, but certainly not impossible.

(I’m just guessing about the failure rate, but I wouldn’t be surprised if it’s in that ballpark.)

I've been thinking about ICBM's comment here quite a bit lately, because I've been buying a few amps, and as you can imagine if you Google pretty much any amp model it's not long before you come across a forum post or two, sometimes by recognised authorities in audio technology, describing the amp's many design flaws and how they basically guarantee catastrophic, wallet-ruining failure.

And obviously they're not wrong - there's no question that most amps are built to a price point and that the resulting compromises often result in factors that make the amp fragile and difficult to maintain.

However I do always try to keep the mindset of the 75% in ICBM's above comment, for the following reason:

The most common factor I've found in amplifier failures is that the owner doesn't look after their amp. Sometimes it's egregious negligence, but mostly it's just a result of people owning what is a pretty niche electronic device, but who don't really understand how it works and how to use it properly, what its limitations are and so on.

Conversely, of the maybe fifty amps I've owned in my life I've never had a single one fail during my ownership fir any reason other than normal wear of components over time, i.e. caps and valves.

I accept there's a good amount of luck involved in that, but I do believe it's also down to the care I take with them. I don't baby them but I do keep them clean and dry and serviced and safe from damage, and they've all, not uncoincidentally, kept going for as long as I needed them to.

All this to say that it's sometimes tempting to read a thread like this and take it as a list of Amps You Should NEVER Buy, but it's important to bear in mind that in probably all cases the substantial majority of any amp model's production run has more or less kept working okay for the duration of its expected life.

ICBM

The only amp I can think of which I would categorically advise anyone never to buy is the Mode Four. I probably wouldn’t even take one for free… it will either die at the least convenient possible time, or possibly blow the speakers when it does, and isn’t even very useful for parts.