Koac V3

PROFANITY WARNING THIS REVIEW HAS THREE RUDE WORDS IN IT
This is a product spotted on the internet and is sold directly by traders in Hong Kong Via E-Bay. They seem to have a good trading record based mostly on selling LED ‘open’ signs. The product comes in a deeply confusing carton which is marked ‘F3’ Although the amplifier is badly screen printed on the upper surface and marked ‘V3’. It also has a model number marked on the heatsink that says GP 103. The end cap is clearly labelled ‘F3’. The illustration does not match the product in the carton as it marked ‘F3’ on the box. Despite an obvious printing error whereby the words ‘FAN COOLING SYSTEM & VU METER OUTPUT LEVEL’ are marked on the box and is clearly incorrect as nothing of the sort is seen in the illustration. The words have been neatly crossed through with two lines of black Biro ink. On the upper right of the box top is the legend ‘2 Channel 2 ohm stable multi-channel circuit design.’ Each face of the carton also shows that the maker claims ‘400 Watts Max Power’. This is also marked on the top of the amplifier itself. It weighs a fraction the mass of a headunit so we doubt this to the point of simple disbelief. One end of the product bears reasonably robust if not bright plated terminals for speaker and power connection and a red LED to indicate Power on status and the other has a pair of RCA sockets, a gain knob and a high-input four pin Molex type socket. A corresponding four-wire lead with a plug is supplied for high level or speaker output level connection although the wire looks too thin for more than three watts. Amongst the rest of the printed claims on the box regarding features, it states the product has a variable bass booster. It does not. If the unit is shaken gently, a rattle can be heard as if a loose internal wire were present.
– Class AB (Marked on top of amplifier ‘The A-Class Design’ which is misleading)
– ‘400 watts max’ output power written everywhere on product and carton
– Aluminium heatsink with black crackle finish and grey coated end caps and base
– 8Ga. Power Terminals with screw down plates
– Screw down plate style speaker connections
– Adjustable input sensitivity
– RCA input and speaker level input
– Stereo, Mono & Trimode operation claimed
– No panel mounted fuse
– HxWxD(mm) 48 x 180 x 143mm
Review by Adam Rayner
I had such severe doubts about this device that to even use the term amplifier instead of ‘Internet scam product’ was frankly, an effort. It was decided to purchase one of these for public information purposes yet it was decided that in the interests of some sort of fairness, we test this item by way of comparison not with a normal car amplifier but with the output chip of the integrated circuit amplifiers found within headunits. It was inserted into the rig that has been set up on the test bench and was compared to the speaker outputs of the Pioneer DEH-P65BT, which is rated at 4 x 50w max and is in fact a true 4 x 22w. At ‘Max’ rating the headunit internal amplifier is rated at half the ‘output’ of the KOAC product, so should be, in theory, only able to raise half the true power of the V3/F3/GP103 amplifier.
First, the headunit was connected to the B&W LM1 leisure monitor speakers and the output measured with the resident sponsored AudioControl SA-3055 real time analyser and SPL meter. Right off the grille and with no special level setting just made as loud as it could go before any distortion was apparent to the ear it raised a serious 118.3dB at the loudest and was stonking. Pure, powerful, crisp and potent, the Pioneer deck can easily run a subwoofer from its RCA outputs via a good amp and the rest of the music will keep up from headunit power alone.
When the KOAC was connected it made a nasty buzzy sound and the transport sounds of the deck were heard clearly as a whiney ‘whoo’ noise. The sound quality was instantly degraded to a soft and ill-defined mush. All impact and definition disappeared. This product does not so much have a noise floor as a noise mezzanine.
In fact, with no signal running at all, the RTA registered 90.3dB of pure nastiness and no music!
With the music running and turned up until the ever present distortion was at least not so strong that you could still recognise the tune, the device raised 115.7dB at maximum at the LM1’s grilles.
I feel like I have soiled my LM1 monitors and insulted both my own ears and the lovely microphone the RTA is equipped with. Upon the moment of relief switching the thing off it went ‘buzzZZZZ SPROINK!’
I can safely say that this device is an arrant piece of utter sh1te. Do not buy one, do not waste cortical processing even looking at one. This is truly a product of the internet age it could not be sold by anyone who actually had to show or demonstrate it in real life. Buyer Beware, this sort of product is pure arrows-in-the-hat cowboy international no-protection lawlessness rubbish.
From the ill labelled box covered in simple LIES, to the impossibly rubbish actual output, this is a misleading and utterly fraudulent product that can give the good factories in China who make whatever quality they are asked for up to and including some of the finest electronics around the sort of blanket reputation that the whole nation could do without. The perpetrator of this crap needs to be locked up and have music played to them through one of these amps until they die.
It won’t take long.
Yes, I can be accused of some degree of prejudging this item but I can safely say that any headunit from any brand NO MATTER HOW CHEAP will sound better and louder- if you simply avoid plugging this phucking thing in.
Recommended use of this product is as a weapon. Nail it to a stick and beat sellers of these to death with it.
(This last statement is of course purely figurative and is in no way intended to be any incitement to violence or any other illegal act deemed antisocial to your societal mores.)
* A new flag has been created especially for this product. It is called the
John Ruskin Award For Utter Uselessness And Total Waste Of Effort And Expenditure
“It’s unwise to pay too much but it’s unwise to pay too little. When you pay too much you lose a little money, that is all. When you pay too little, you sometimes lose everything, because the thing you bought was incapable of doing the thing you bought it to do.”
John Ruskin (1819-1900)
Overall Minus 0.6
Sound Quality Minus 3 (sonic degradation)
Power Output 1
Features 2
Build Quality 0
Value For Money Minus 3 (internet scam theft)