STARTING a diesel engined car first thing in the morning can sound as though the army has launched a mortar attack under the bonnet. Not a good way to begin the day.

But, with something like the mid-sized Mazda3 hatchback it gives a distantly throaty rumble before quickly settling into a scarcely audible thrum. That's more like it.

A combination (techie bit coming) of the lowest compression ratio on any diesel car on sale and something Mazda calls Natural Sound Smoother technology are responsible for this cold start hush.

The sound smoother reduces diesel knock on starting and during low speed acceleration. The low compression ratio cuts the size of the bang each time the fuel ignites in the engine and the combination is a pleasantly refined engine.

Add in some extra sound deadening when the whole Mazda3 line was gently upgraded some months ago and you have a car capable of carrying you and the family a long way without anyone needing to raise their voice.

But, you may be asking yourself, why all this talk of diesels when we all know they're the spawn of the devil and deserve to be banished to the eighth circle of hell? Surely, Mazda ought to be selling only petrol versions of its cars these days?

Well, most Mazda3 sales are for petrol models, not least because they're a more than useful £2,200 cheaper than the diesel equivalent. But for longer distance drivers a diesel still makes heaps of sense.

After some demanding driving in the diesel test car its trip computer showed 54.7mpg. I'd call that a result, and loads better than you might achieve with petrol providing the power.

For longer distance drivers there's another bonus, in the way the diesel simply wants you to get into a higher gear and relax. It's a seductive way to gobble up the miles, letting the diesel's lack of drama leave you fresh and ready for more at journey's end.

Should you feel like injecting a bit of drama you'll find the Mazda3 a willing co-conspirator, with a deliciously positive gearchange, precise steering and an eagerness on corners that single the car out.

Dig deeper and you discover Mazda has been clever with the electronics in the latest edition of the Mazda3, devising something called G-Vectoring Control, which minutely varies the power going to the front, driven wheels to keep the car tracking straighter, to the benefit of both feel at the wheel and passenger head-nodding comfort.

Inside, there have been modest upgrades with better materials for switch and handle surrounds, leather steering wheel and the old-style manual handbrake is replaced by an electronic parking brake, freeing up space for a couple of cupholders.

The traditionalists among us are allowed at this point to shed a tear for the passing of a 'proper' handbrake, even if nobody applies a parking brake of any sort these days.