I recently bought four Hypex UCD400 OEM V6 and V7 modules second hand, four new SMPS400 power supplies from Hypex, then hooked everything up and... What a disappoitment! Two V7 of four UCD modules outputs DC voltage! I don't know the history of these modules. One pair is totally good, one pair ouputs DC to the output.
1. I shorted inputs to the ground and there is still DC voltage at the output.
2. I measured 5-6V DC when using buffered input and about 1V when using unbuffered input.
3. DC voltage is drifting constantly, it is not constant over time.
4. The issue is equal on both modules in faulty pair of amps. Other pair is completely fine.
5. I use OEM adapter for connecting signals and power. In every case the connection scheme is equal.
6. The DC-protection is not tripping in. Amps are operating normally despite DC voltage. Control pins for DC protection are connected properly.
7. I connected the source and the speakers for a trial. Drivers are vaving after power-on and are being pushed-in especially on buffered input.
8. There is music playing for both buffered and unbuffered inputs. But there is excessive bass amount. A plenty of bass.
9. There is no hum or hiss, the amps are dead silent, powerful and without distortion (for my ears).
10. I don't know the history of the UCD modules. They looks like noone had modded/resoldered it.
As I am individual and these are OEM modules I cannot rely on Hypex becouse they probably will not bother with me in this case. I am completely alone and someone seems to make a fool from me selling faulty modules without any warning. I have a little money in my life, big aspirations, I simply wanted to hear at least good amp... And I've got a piece of s...t! What I should to do now? 🙁
1. I shorted inputs to the ground and there is still DC voltage at the output.
2. I measured 5-6V DC when using buffered input and about 1V when using unbuffered input.
3. DC voltage is drifting constantly, it is not constant over time.
4. The issue is equal on both modules in faulty pair of amps. Other pair is completely fine.
5. I use OEM adapter for connecting signals and power. In every case the connection scheme is equal.
6. The DC-protection is not tripping in. Amps are operating normally despite DC voltage. Control pins for DC protection are connected properly.
7. I connected the source and the speakers for a trial. Drivers are vaving after power-on and are being pushed-in especially on buffered input.
8. There is music playing for both buffered and unbuffered inputs. But there is excessive bass amount. A plenty of bass.
9. There is no hum or hiss, the amps are dead silent, powerful and without distortion (for my ears).
10. I don't know the history of the UCD modules. They looks like noone had modded/resoldered it.
As I am individual and these are OEM modules I cannot rely on Hypex becouse they probably will not bother with me in this case. I am completely alone and someone seems to make a fool from me selling faulty modules without any warning. I have a little money in my life, big aspirations, I simply wanted to hear at least good amp... And I've got a piece of s...t! What I should to do now? 🙁
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