HiFi Subjectivist ¦ Audio Forum ¦ NVA User Group

When one of the many dissers and damage attempt(er)s of NVA product want to insult us they say we make plastic amps, well yes acrylic is a plastic as plastic means :-

"Plastic is material consisting of any of a wide range of synthetic or semi-synthetic organic compounds that are malleable and so can be moulded into solid objects."

Now this covers a wide range of material both in cost and effectiveness for different jobs from the film that covers your sausages at Tesco to acrylic which was developed originally as a replacement for glass.

It is the same for metal which varies from pig iron to gold, yet say something is made of metal and it is not an insult yet calling it plastic is considered an insult. I use acrylic for a number of reasons but mostly because I build to classII appliance regs as opposed to classI which is earthed metal case. classII is double insulted case with no mains earth connection. Acrylic gives me a vital first layer of insulation. I use it for other reasons due to metallic eddy currents and other things that effect and block the music in metal case amps IMO.

The other thing that is important to get across to you is cost, yes plastic cases can be made very cheap with cheap plastics, but acrylic cases cost more than aluminium or steel cases in equivalent size and complexity. Others have used acrylic, yet it seems the insults are reserved for NVA.

Discuss

It's just people taking a cheap shot.

They don't understand that good engineering involves the use of appropriate materials in appropriate thickness.

The chassis of my upstairs turntable is made from plastic. Does that mean it's cheap rubbish? It's an EMT 930.

"They don't understand that good engineering involves the use of appropriate materials ....."

hits the nail on the head. I worked in plastics R&D for ICI for about fifteen years and remember being told how "plastic" became synonymous with cheap and nasty during the fifties and sixties as a result of polymers being used in inappropriate applications - people forgot/never appreciated that the Spitfire bubble cockpit canopy was made from acrylic.

One inappropriate use of a polymer can be seen in Linn LP12 dust cover hinges - the spring (metal) bores its way through the plastic hinge material resulting in early failure (or maybe that is deliberate ). I found a way of reinforcing the hinge with a small strip of metal at the contact point, no more problem.

By the way; I know that language develops but clay (inorganic material) is a plastic material (can be moulded).

The use of ‘plastic’ is what attracted me to Nva. I thought- that’s different and are good looking amps -

Wasn't there an amplifier encased in a solid block of acrylic? Early/mid 80's, possibly from Carver?

The way in which NVA amps are housed in non-metal casings for SQ reasons is perfectly logical - and acrylic is an ideal choice for a speaker enclosure: strong, solid and non-resonant.

NVA equipment looks good as well as sounding good. The small size of the starter system is a big plus for me. However, i think this would be a negative to those who do not put music first and like big boxes.

.... or shiny brushed-metal casings.

"Plastics" are uses in all sorts of places, the Boeing 787 being a good example, nobody is calling that "Cheap and nasty plastic". Airbus have used composites for stabilisers for many years without negative comments. In both cases that is probably because the general public are ignorant or bamboozled by the term "Composite".

The NVA casings look sleek and timeless and they wear very well (with minimal application of Windolene!).
As the Doc says, they are there for sonic reasons.
The only negative I can think of (having lived with NVA for 30+ years) is they do attract dust.
Naim are using acrylic these days.

Metal = Heavy = Good
Plastic = Light - Bad

That is, of course, a complete load of bollox, but I'm sure it's sometimes how people without any requisite knowledge (are taught to) think. Put a tatty little circuit inside a block of milled unobtanium alloy and it *must* be a good amp.