Need advice (could be a waste of time)

[plastic penguin]

It's a question about killing speakers. No, not mine they sound great.

Been speaking to a guy in our village about music, and he mentioned he had a Denon integrated and using Q Acoustics standmounts he purchased from Richer Sounds in Guildford. It transpired he's killing his speakers.

He's no idea what model of Denon amp (model number) and can't tell me what Q Acoustics he has. It's a bit weird, but guess it's entry-level models of both.

Apparently the speakers are distorting and he's purchased 2 sets of Q Acoustics and both have died. That's madness.

I asked the basic question, has he tried using headphones? If it sounds wrong on phones it's a amp issue. He doesn't have headphones. Does he play music too loud? He said no.

I've given him my mobile no and said I'll go through some cursory checks with headphones and might even take my old Arcam Alpha 7 and see if that makes a difference.

I've known this guy for around 2 years and seems genuine but doesn't seem too sharp when it comes to his system.

Any pointers would be appreciated.

 

[Al ears]

Not sure what he is doing to them or connecting them but there is no way any Denon amp should kill any Q Acoustics speakers...
Headphone output will make no difference and will not point to any problem as far as I can see, it's totally irrelevant.

 

[James105]

Tone controls wound all the way up?
Maybe suggest he downloads a free SPL meter for his phone and see how loud hes really playing it?

 

[Vincent Kars]

Apparently the speakers are distorting

Clipping?
DC offset?

 

[podknocker]

If it's struggling with the impedance of the speakers and it's an underpowered amp, then clipping would seem to be the cause. IF the amp's not controlling the speakers, then this will happen. Underpowered amp, low current and damping factor. I broke a pair of Tannoy 603 speakers about 26 years ago, trying to play them loud, using a Kenwood KA3020 amp. They were a bad combination. The Tannoy's were a very tricky load and about 85dB sensitivity also. It made a right racket when they popped.

 

[plastic penguin]

Not sure what he is doing to them or connecting them but there is no way any Denon amp should kill any Q Acoustics speakers...
Headphone output will make no difference and will not point to any problem as far as I can see, it's totally irrelevant.

My theory is if it's not distorting through the headphones it should point to the speakers.

 

[plastic penguin]

Clipping?
DC offset?

No idea. I'm just telling you what he's told me. He doesn't seem to be clued up on hi-fi, but to go through 2 pairs of speakers in 2 or 3 months something isn't right.

 

[Al ears]

No idea. I'm just telling you what he's told me. He doesn't seem to be clued up on hi-fi, but to go through 2 pairs of speakers in 2 or 3 months something isn't right.

no way clipping is a problem.

 

[nopiano]

My theory is if it's not distorting through the headphones it should point to the speakers.

It depends how the headphones are driven. But in a cheaper amp it’s most likely the power stage padded down with a circuit.

Rather that let him loose on your amp, how about he lends you his? Or takes it to RS?

 

[plastic penguin]

It depends how the headphones are driven. But in a cheaper amp it’s most likely the power stage padded down with a circuit.

Rather that let him loose on your amp, how about he lends you his? Or takes it to RS?

No way is he going near any of my everyday kit.

He reckons he phoned RS and they weren't too helpful.... I've never had a issue with the company. So I offered to take him down there as he doesn't drive, he could rig his kit up but he didn't seem too keen.

 

[plastic penguin]

no way clipping is a problem.

When I go around his gaff I'll check all the cabling, if it is distorting.

Until I hear it it's a real puzzle.

 

[Gray]

When I go around his gaff I'll check all the cabling, if it is distorting.

Until I hear it it's a real puzzle.

Get a DC meter (yours or his multimeter) on the speaker outputs first.
Confirm a low millivolt reading on each channel. Could be a positive or negative reading, but close to zero is what you want.

 

[plastic penguin]

Get a DC meter (yours or his multimeter) on the speaker outputs first.
Confirm a low millivolt reading on each channel. Could be a positive or negative reading, but close to zero is what you want.

Cheers @Gray

 

[matthewpianist]

Q Acoustics are easy to drive and present no real challenges to even fairly modest amplification. He's either got the Denon turned up too high (and most amps with standard volume pots start distorting with the volume approaching the 12 o-clock position) or it's sending DC out to the speakers.

 

[plastic penguin]

Q Acoustics are easy to drive and present no real challenges to even fairly modest amplification. He's either got the Denon turned up too high (and most amps with standard volume pots start distorting with the volume approaching the 12 o-clock position) or it's sending DC out to the speakers.

This is what I told him, thanks for confirming my initial thoughts.