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nikita
19-04-2015, 15:57
Hi All,

A little bit stuck on this one and don't want to damage anything through ignorance :-)
Right so I got the speakers, amp and subwoofer below. Question that I need an answer to is it safe me using the amp for this speakers. Seems a bit underpowered and I don’t want to damage speakers by "clipping".
I used to have a bigger amp but no longer and I don’t know if it enough power to pull the 4 speakers and the sub? I am thinking if something like a Audiolab 8200X7 7 Channel Power Amplifier would be more appropriate?

Harman Kardon HK3490 stereo receiver
120 Watts per channel 20Hz-20kHz@<0.07% THD both channels driven into 8ohms
Signal to Noise (IHF-A) Ration 95dB

And speakers:
2XWharfedale Diamond 10.5
Suitable Amplifier Power 20-120 Watts
Impedance (Nominal) 6Ω
A/V Shield no
Sensitivity 86dB

2XWharfedale Diamond 10.6
Suitable Amplifier Power 20-150 Watts
Impedance (Nominal) 6Ω
A/V Shield no
Sensitivity 88dB

Wharfedale Subwoofer Diamond 10.GX-SUB
Bass Driver 1x250mm
USB 5V Ouput No
Amplifier Power 250W
Line Input Sensitivity 325mV for 150W
Avg. Max Output @ 1m 113dB
Boundary Response 30Hz - 100Hz
Crossover Range 35Hz - 85Hz (6x10dB steps)

Any help, advice and opinions are most welcome.

Regards,

Nikita

struth
19-04-2015, 17:23
I dont think the amp will be found wanting tbh Nikita. Its quite a powerful unit and is designed to take a sub, (possibly 2) and 4 speakers. the warfendales' shouldnt be too hard to drive even though they are not super efficient.

Macca
19-04-2015, 19:07
The sub has its own amp so is not a factor. It is usually advised that if running 4 speakers off a receiver designed for it i.e with two sets of speaker outputs, that you use speakers that are 8 ohm or above all round. If you whack the volume up for an extended time you might blow a fuse or trip protection, But you'd have to go for it.

nikita
20-04-2015, 11:05
Thank you very much for your replies.

So just to sum up no damage will be caused unless I am really hammering the system?

Regards,

Nikita

Macca
20-04-2015, 11:10
That should be the case, yes. :)

Brigadoon
20-05-2015, 07:46
Thank you very much for your replies.

So just to sum up no damage will be caused unless I am really hammering the system?

Regards,

Nikita

Encouraging to see a question about damaging speakers with a lack of power :)

I know this is a bit dated, but just an observation FWIW...

The HK setup that Nikita has will handle the Wharfy's, and shouldn't have any issues unless being run at stupid volume levels.

However, dynamics is a far more important aspect of a successful HT setup than volume, and for that is best to always have a lot of amplification headroom. For 86dB speakers rated up to 120 Watts, I would recommend an AV amp that can handle 200wpc. This will ensure that at moderate listening levels, the amp will easily handle the transient power demands necessary for good dynamics.

The other way to approach this would be to go for slightly lower power rated, more efficient speakers. Either way TBH if I was advising Nikita, I wouldn't have recommended the combination she is using.

Macca
20-05-2015, 12:44
Would it not be the case that the sub, driven from the LFE channel, would handle most of the dynamics anyway? And relieve the speakers from having to re-produce the bass frequencies. Just a thought.

Brigadoon
20-05-2015, 17:30
Would it not be the case that the sub, driven from the LFE channel, would handle most of the dynamics anyway? And relieve the speakers from having to re-produce the bass frequencies. Just a thought.

That's a fair point,and the common thinking with HT however, more dynamics occur in the mid-top range than we think. Our perception that HT is onl;y impressive when explosions make the room vibrate is a by-product of the way HT systems are marketed people are initiallly impressed by thumping bass, so that's what the sellers push.