What does a bigger amp bring to the party?

Hi all

How does an amp change things within ones system.
All the Naim amps set at the same decibel range I.e 20db. What do they do differently to one another?
I know speakers can have different sensitivity’s and this has a bearing.

Cheers

Move the speaker cone faster - or rather, accelerates (and decelerates) it faster.

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So you mean that a low powered amp will play a 100hz note at say 70hz instead… Sounds reasonable to you?

No - it should play it at 100 Hz, but it won’t, perhaps, follow the full curve. Suppose the frequency of the signal is 100 Hz, and the maximum voltage is + and - 24 Volts (not a very high voltage, I suppose). Let’s make it a simple sine wave. If there isn’t sufficient power there, there might not be sufficient amperage to move the cone as fast as it should, so instead of a sine wave it might be a slightly different shape. Also, the cone might not move as far as it should. But the frequency of whatever it manages to do should be about 100 Hz. It is to do with slew rate - the rate at which the amplifier can get to the required voltage - and the power available (so more easily-driven speakers should sound better than more inefficient ones).

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It surpresses upgraditis for a while and then it comes back more seriously.

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A small area of the midrange will sound relatively the same as anything.
It’s the way the extremes - bass and treble - are handled, in time and in the right place…

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Smaller amps have smaller power supplies. These clip easily, putting DC onto the voicecoils. This then sounds like not very nice distortion. Most amps power rating is limited by their power supply to the rails.

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Yes, I understand that. But I am guessing that the majority of people listen at a volume 90% of the time that isn’t pushing an amp at the point of clipping.
If this is the case how does an amp with lots of power in reserve better another smaller amp at normal listening levels.

Is it purely then speaker sensitivity that comes into play?
If so, how does a highly efficient speaker benefit from a lager power amp?

I was amazed when I had my MF A300cr reworked. Loads of stuff changed, caps etc, but it wasn’t from 27kgs to just short of 40kg. Oh yes. I had to change the MCB due to inrush current on start up.
The sound at very modest levels of and do much more grip. Having absolute positive control over the speaker cones. They did exactly what they were told to do.
I’ve never got my volume control past 11 o’clock. Still controlled. It masters my PMC 20-26s.
But put a small pair of DALI speaker on the amp and those small speakers sing.

Within reason you can’t have too much power providing your budget can take the strain.
Just an easier listen all round. Small amps when pushed can damage loudspeakers. More power always good.

There’s more to it and probably a lot of variables. A 282 doesn’t sound anything like a 252. The 552 doesn’t sound remotely like any other Pre in the Naim range, regardless of what speakers they are driving in which room.

Apart from sonic signatures that differ, the thing that comes through the most to my ears is grip. The ability to move a cone in both directions more easily, and to exert finer control over acceleration, throw, deceleration, etc. without getting muddled or breathless, seems to take away more than it adds. What’s left is clarity and realism.

Our little Spendor S5e matchsticks sounded absolutely amazing once a 500 got behind them. Grip and control. You can’t beat it.

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Found that complex bass passages became less muddled.

Greater ability to handle large and abrupt changes in dynamic range without raising a sweat.

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I think it is similar to having a bigger engine in a car. A car can go at a steady 70mph say, whether it has a 3 litre engine or 1 litre. But the larger engined car will respond effortlessly if it has to cope with an incline or some other change, whereas the smaller one will struggle with even minor challenges.

I know power is just one factor but responsiveness is the key thing I have noticed when upgrading power amps or power supplies.

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That seems an excellent analogy!

Continuing the analogy, of course “more powerful” can be considered in different ways with an amp, just as with a car and measures such as cylinder capacity, BHP, torque, Power/weight ratio etc, all describing something different, yet all valid measures in their own right: So an amp has factors such as max continuous power, max peak power, max current, slew rate, so an amp might not have the highest max continuous power (the most common power rating), but might be the most capable.

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There was once the analogy that big amps are like big cars. Ok cruising on a straight road, but can get into trouble on the close corners.
A smaller car might rattle a bit cruising, but comes into its own being light and nimble on those close corners.
I would guess today’s amp technology has moved on from that.

Damping factor can be important too. Ratio of speaker impedance to amp output impedance.

…and add into this the concept that loudspeakers are reactive (including ‘changing’), loads, then there you have it. But one proviso…the acceleration of the cones is as a result of force, not power.

With apologies to the OP, is this the reason the first two Naits are so revered?

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Indeed I remember, in the 1980s, when I got my Nait 1, being astounded at what (OK, pun intended) 12 Watts could do!

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am quoting from your post but this not - at you…

Depending on speaker design - many of speakers do not like to be controlled too much…in-fact Lowthers and Fostex drivers sound best with amps that don’t force the speaker cone movement too much. This kind of speakers like to be tickled and persuaded and not pushed and poked in the rear with more power for maximum musicality.

In our Naim community - such speakers are less but they are out there…

so the general impression that more power brings more control implies that all speaker cones like to be controlled - which i want to dispel.

Some speakers dance with amplifiers which match its general disposition…

Other speakers - like the amplifier to be the macho guy / gal and force control the speaker cone movement as per the signals from the pre amp

So everything depends on the chain and there is no single answer to a generic question is my submission.

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