Thank you Global, I really appreciated.
I0ve seen this on ebay but there isn't no notes if is a mkii version
WONDOM 2X 400Watt Class D Audio Amplifier Board Compact - T-AMP Module Stereo | eBay
I0ve seen this on ebay but there isn't no notes if is a mkii version
WONDOM 2X 400Watt Class D Audio Amplifier Board Compact - T-AMP Module Stereo | eBay
That's the genuine Sure/Wondom ebay shop. Since a lot of shops are already selling the MK II I'd strongly assume they don't have any of the old version anymore for quite a while.
I find my Sure 2 x 500W (AA-AB32512) amp board speaker output is intentionally clamped @ 48V.
I tried to raise the supply rail voltage to 60V (STA516BE should run safely under 65V), However, the maximum output voltage is clamped at 48V Peak (34V RMS). This gives me an unsatisfying output power (144W/each CH)under 8Ohm load.
Anyone have tried out AA-AB32514 ? I am wondering if this(clamped behavior) is the difference between AA-AB32512 & AA-AB32514.
Maybe AA-AB32514 is not clamped for higher output power (?)
I tried to raise the supply rail voltage to 60V (STA516BE should run safely under 65V), However, the maximum output voltage is clamped at 48V Peak (34V RMS). This gives me an unsatisfying output power (144W/each CH)under 8Ohm load.
Anyone have tried out AA-AB32514 ? I am wondering if this(clamped behavior) is the difference between AA-AB32512 & AA-AB32514.
Maybe AA-AB32514 is not clamped for higher output power (?)
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Well, 144W is probably not satisfying for you but please have a look at the numbers: The maximum power at 48V is specified at 10% THD with 500W at 3 Ohm! and 270W at 1% THD.
If you cut back the THD (noone listens to 10% THD of an amp), it gets lower ofcourse. But let's calculate it.
P = U² : R
34V² : 3 = 385,3W
380W, assuming that's at lower than 10% THD, it's perfectly normal. The datasheet says it's 270W@3ohm 48V DC THD+N 1%.
It actually IS - but ONLY at lower impedances. I don't know what to say, the specs are pretty clear about at which impedance the power is delivered.
I don't get it. Where can I get a 3 Ohm impedance speaker ?
I know there're some special designed car speaker have dual 4 Ohm voice coil.
But I've never seen any single speaker with 3 Ohm or 1.5 Ohm impedance.
If 3 Ohm speaker is rarely available, what's the point of saying it "500W @ 3 Ohm"? (a wattage that you can never achieve ?) 😕
You use i.e. 3 8 Ohm subs. Or you build it yourself. Or you use a commercialy produced '8 Ohm' speaker - which got a glorious minimum impedance of 2,8-3,5 Ohm. And yes, there are not too few of them out there. 🙄
Well, like already said above, a there are speakers which got a hefty dip in the impedance. Then there are 8 Ohm labeled speakers which are, in fact, rather 6 Ohm (Re ~5 Ohmj or lower). For extra-WAF these drivers are often used in pairs to get these elegant, slim towers.
In any case, they did not make any secret out of the circumstances how the power can be achieved. I somehow don't see how they made a mistake there and that's certainly not the 'fault' of the amplifier. I mean, the culprit would be the one who didn't read the specs properly and just went for huge wattage numbers, wouldn't it?
What do you mean with spike at 1k? Do you mean at TIM or THD measurements? 1kHz is usually the test tone it is measured with.
I ordered the Chinese PCB 3255, I want to compare it with the Gremlin 400w. I do not think it's better.
on the Gremlin I changed smd capacitors (coupling) by MKP Obbligato copper.
on the Gremlin I changed smd capacitors (coupling) by MKP Obbligato copper.
Both amps have the same chip, even the STA516be.
As mentioned by ICG, the power is the same with the % of voltage
Yes, the 400W one got a SNR of 96.7dB/204µV noise, the 500W got 95dB/240µV noise on the output voltage at maximum 1%THD rated power. But since you can't hear that, I dare to claim they sound exactly the same.