Amps that have fried your speakers and other exciting adventures in hifi

[Tryant]

Now here's a cheery topic. How many of you have had the depressing experience of your amp suddenly taking out your woofers?:eek: Happened in a nanosecond with my wife's Musical Fidelity amp. Didn't realise there wasn't any protection in the circuit to prevent this happening. I think that's what used to be called the 'Purist' approach to amplifier design for better sound.:rolleyes:

[Firebottle]

Was working on a little switch mode converter to power an in car amp, run from 12V, quite a small unit.

Thought I would give a quick test without bolting the switching transistor to its heatsink, big mistake.
The plastic bodied transistor heated up so quickly that there was an actual flame coming from it - oops.

[icehockeyboy]

Years ago I had a phenomenal American amp, it was a Phase Linear, 350 RMS per channel into 8 ohms, 450 into 4 ohms, it was feeding speakers that at the time were the only ones that could handle the power, Bose 901’s.

I had been away, leaving my set up in the hands of a friend, who had promised to take great care of it.

I think you can guess the outcome of this tale!

Upon my return, first thing I did was want to listen to my beloved Hifi , only to realise that one channel was completely dead!

Further inspection revealed that all 9 speakers in the Bose were fried, caused by the massively powerful amp going DC on one side!

Luckily AR Teledyne who were in charge of importing them at this time replaced it free of charge, as did Bose, with not just 9, but 18 brand new drivers, so a happy ending!


Sent from my iPad using Tapatalk

[eisenach]

Musical Fidelity Electra 100.

Fried my Rogers LS6as. I was very cross. Managed to find a distressed cabinet pair on ebay and cobbled together one good set. Had the amplifier repaired. It happened again. By now LS6as had become fashionable and expensive. Oh, well ...

[Tryant]

Do I detect a sub-thread in this thread? I had one of those Electras too at some point some years ago. This was one of those X-thingies with the cool extruded cases that were popular back in the day. MF must have spent more on the case than the junk inside. It did however sound very good when it was working. Took out the woofers in a pair of P3ESR's.

[hifi_dave]

Exposure power-amp, Michell Alecto and AVI power-amp. All went poof without any warning. That's not many considering the thousands of amps I have had pass through my hands.

[Lawrence001]

I was selling an ESS power amp from the 70s , powerful thing with fuses before the speaker outs. Anyway, I was giving a demo of it and something happened, I forget what, might have been a thunderstorm, the fuse blew, and I didn't have any spares. He was a professional off road driver and offered to do a "field repair" which consisted of wrapping tin foil round the fuse and replacing it. Put the amp back on, one woofer immediately blown. The amp was fine, I think it was the residual charge in the huge caps that did it. Cost me about £100 to get a used replacement woofer from the States, I was actually lucky there were any available globally and he did buy the amp despite the problem.

Sent from my BLN-L21 using Tapatalk

[spendorman]

In 1976, bought a new Quad 405, immediately blew a KEF B200 in my home-made Collom's Mini Monitors. !00 Watts was just too much!

Had both B200's rebuilt by KEF.

[Sherwood]

who's going to tempt fate and say it's never happened to them? :uhho:

[montesquieu]

who's going to tempt fate and say it's never happened to them? :uhho:

Not me.

Fried a Tannoy 15in Monitor Gold when a Krell SA50 went DC on me in the left channel ... first thing I knew about it was the smell of burning paper, then I saw the cone begin to char from the centre by the voice coil, travelling outwards like the map in the credits of Bonanza.

They had to be re-coned as a pair, £600+ to Lockwoods thank you very much. Got about half back from the house insurance.

Took a good six months to sound the same too as the thick bindings on new MG cones take a bit of loosening up.

[struth]

Guess its up to me then :lol: Ive already had the thought it so the game's a bogey anyway. Not fried a driver as of yet. touch wood

[Haselsh1]

I remember back around 1979/80 having a Naim NAC42/NAP110 pre/power combo that blew one of the bass drivers in my QLN Mk1's due to large heavy thumps on switch off that was only cured by the purchase of a SNAPS power supply that no one bothered telling me about at the time of purchase. What I thought was a bargain of a Naim became quite expensive at the time. Live and learn I guess.

[nonuffin]

who's going to tempt fate and say it's never happened to them? :uhho:

I have never fried any speakers or amps for that matter, although I bought a PS Audio HCA2 power amp that exploded when I plugged it in. It was a 110 volt unit but the shit bag seller had ripped all the labels off the unit including the box so I had no idea what voltage it was.

[Yomanze]

Guess its up to me then :lol: Ive already had the thought it so the game's a bogey anyway. Not fried a driver as of yet. touch wood

Touch wood, me neither, but I think the speaker output 'quick blow' fuses would go first.

[Pharos]

My experience of a Naim 250 with a pre, was that some of the earthing arrangements were rather odd.

[goraman]

It happened to me once with a Sansui A3000 receiver it simply fried both speakers at power up with the volume down, I was told it had gone to DC but have no idea why an amp would do this?
Could someone explain this ?

[nonuffin]

It happened to me once with a Sansui A3000 receiver it simply fried both speakers at power up with the volume down, I was told it had gone to DC but have no idea why an amp would do this?
Could someone explain this ?

An amp's power output is derived from DC supplied by the power supply by the music signal modulating that DC power via the output transistors/chip/valves/transformer into an AC waveform which is then fed to the loudspeakers.

At power up, there can be a huge inrush of current to the reservoir capacitors and in effect that is a partial AC waveform which is passed on to the output stages. Different parts of the driver and output stages react at different speeds, so at one point a DC component appears aat the output and passed on to the speakers, which we hear as a loud thump.

[Sherwood]

At least most forum members don't have to worry about power surges. I was working in Bangladesh in the mid 90s when a lightning strike on an electricity sub-station next to our office caused a sizeable explosion and a power surge that "killed" several pc's. I was working on a laptop and lost the entire hard drive and several weeks work, It took me about two weeks to imperfectly re enter info from my handwritten notes. It taught me two lessons, don't leave equipment plugged in during storms, and to email myself working files at regular intervals to avoid data loss.

The problem is getting worse in Bangladesh for several reasons. One possible explanation is that the high degree of particulate pollution in the air makes ground strikes more likely. In any event, this years death toll has been particularly high.

https://www.dhakatribune.com/bangladesh/nation/2018/05/22/lightning-strikes-kill-200-in-75-days

:stalks:

[ianlenco]

I've not had speakers blow up but quite recently I had an amp emit sparks and smoke when a friend connected it up to his speakers - I'll say no more to prevent any embarrassment :eek: apart from the amp, a Wyred 4 Sound MiNT is well and truly fried.

[Bamby]

Oh dear, this brings up very bad memories! ...

Went for a Belles 150A and thought it would be my ultimate.
It blew up 4 speaker units in total.
Then importer/Dealer gave no support. He blamed me.
Took about 5 months to get the part for the amp.
Took me 11 months to get the speeks fixed.

Ah ... what (epensive) memories!

[sumday]

I was always working on a budget in the early 90s and lucked in on a very cheap pair of Celestion SL6s.
Partnered with a Harmon Kardon 665 and a Marantz CDP i was treated to good sounds for not much cash.....for a short time.

I still have no real explanation as to why the amp played up, but it simply fried the coils of my speakers without any provocation.
Fine one night at switchoff...dead the next day.

I was out during the day and initially blamed my teen daughter for caning the stereo....she cried.

Thinking it was a case of too many watts i conected another pair of speakers and had a sulk.
The amp played fine for a short time then motorboated badly.

This was before easy tinterweb diagnosis and repair so my caveman genes got the better of me and i ripped out the amp and grunting badly heaved it into the bin....swiftly followed by the blown speakers.

All i've suffered since is the cat thinking my speaker grilles were scratch posts......its funny how loud you can shout when that happens.