Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems G57 with 4Ohm

Can the G57 amplifier handle a 4Ω load?

Does anyone know what sort of power output it is capable of with a 4Ω load?

G57 "can" handle 4Ohm load delivering 330W, but i would not recommend. According to my experience you'll get strong emphasis on bass; highs may become harsh.
i have checked with Sonus Faber, Thiel and Legacy. best result so far i have with Vandersteens.

Hmmm, my mileage varied. And I'm basing this on the assumption that the G57 is similar to the 557.

My Kefs are 4ohm nominal, with dips to 2 ohm at some frequencies. It took a move to 557s to contain this, and they did a spectacular job. I hadn't compared with as high quality competition as Ivan, but I had noticeable dips at 60Hz (the main 2R offender) with my prior Arcam. The 557 was still capable of driving linearly down there. I had the effect of extra bass after the upgrade, but it was simply the output not dipping in the crossover region like it did with a less current-capable amp.

For low impedance loads, you want an amp with a very high current drive ability. This tends to require a huge transformer and lots of high power output transistors. The specs will show massive power outputs for low impedances and bridging (which halves the effective impedance since the other end of the load is being 'pulled' by the other channel). Basically, the amp will appear to be overbuilt for its rated power output. Distortion will increase as the output stage and power supply is more heavily loaded (which may explain Ivan's harshness commment), and the spec's should include distortion at 4R (or be worst case figures across the rated range of the amp).

Personally, I've always thought that this is one reason that people find really powerful amps to sound great at lower volumes - the reserves are there to handle any non-linearity in loading from the speaker.

Unfortunately, the G57 is not exactly similar to the 557. It's actually a quite different design.
Had the question have been about the 557 I'd have answered yes without the slightest hesitation. I drive speakers that dip to 3.7 Ohm (the impedance is a function of the frequency/spectrum of the applied input signal) with a 557 and there's no problem whatsoever.

I can only guess that the G57 will handle well 4 Ohm loads, but it's only that : a guess. Perhaps someone with a G57 can shed more light on this.

Thanks for the replies/thoughts.

I've taken the plunge on the G57 and am probably going to go for speakers which are 8Ohm nominal, 6.4 minimum.

I was considering some Sonus Faber (which is why I asked) speakers but they got snapped up before I had a chance to demo them.

Mr Dog,

Could you expand upon the differences between the 557 and the G57?

Thanks,
Mark S

I can't honestly expand too much on that. And I should have been less assertive - I have this information from about 3 years ago or so when my kit was serviced. Although spare parts for the G57 were at hand, none could be fitted to the 557 "because of the differences in design". At the same time, the G02 was said to be mostly a repackaged 502, while the G57 was different from the 557, and not only in looks and specs.
By different I did not imply better or worst.