I just reviewed the VTV Purifi amplifier with SIL 994EnH-Ticha input gain/buffer stage. This is a quick teardown of the unit.
Click on this image for larger size:
Take care of the obvious, the two larger modules are Hypex SMP1200 power supplies. In between them, the little boards to the left are the Purifi amplifier boards (with green PCB). To the right of them is their custom input buffer that allowed interchangeable opamps. While this board is made for a ton of flexibility, I am not happy with the long path lengths here. They can pick up noise and interference. The reference design from Purifi uses PCB mounted XLR connectors that provide a very short path to the input buffer IC. Not so here with those long cables (in comparison).
I also find the placement of the upper channel rather odd. Why not have it further up so that it can have a shorter path to the input and output?
The biggest safety issue I see is the mains wiring in black and white on the left. There is no hold down so they are touching the two heatsinks. Those heatsinks get hot. Depending on the temperature rating of the insulation of those wires, it could melt them over time and cause a dangerous short. Mechanical vibrations can also saw through the insulation with the sharp edge of the heatsink.
The top Molex connector is also used as a junction to feed the second power supply. I don't like that. I rather see a T upstream feeding both power supplies with equal length wiring (to be really anal about it ).
I am puzzled by selling an amp with those giant speaker biding posts but with skinny wires on the inside. I would shorten those wires and make them beefier.
There are also fine wires flapping in the wind for different power supply feeds for trigger circuit and such. They cross the main power supply wiring which could subject them to noise pick up.
Conclusions
Much of the heavy lifting is performed thankfully by the Hypex and Purifi modules. The assembler's job is to put these together in a safe and performant manner. I don't think that has been done here. Suggest a clean up path with input from community here to improve the design without much cost hit. As a minimum, the mains wiring needs to be tied down and away from heat sinks. Yes, chances of a short is one in a million. But do you want to be that one in the million?
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As always, questions, comments, recommendations, etc. are welcome.
Appreciate any donations using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
Click on this image for larger size:
Take care of the obvious, the two larger modules are Hypex SMP1200 power supplies. In between them, the little boards to the left are the Purifi amplifier boards (with green PCB). To the right of them is their custom input buffer that allowed interchangeable opamps. While this board is made for a ton of flexibility, I am not happy with the long path lengths here. They can pick up noise and interference. The reference design from Purifi uses PCB mounted XLR connectors that provide a very short path to the input buffer IC. Not so here with those long cables (in comparison).
I also find the placement of the upper channel rather odd. Why not have it further up so that it can have a shorter path to the input and output?
The biggest safety issue I see is the mains wiring in black and white on the left. There is no hold down so they are touching the two heatsinks. Those heatsinks get hot. Depending on the temperature rating of the insulation of those wires, it could melt them over time and cause a dangerous short. Mechanical vibrations can also saw through the insulation with the sharp edge of the heatsink.
The top Molex connector is also used as a junction to feed the second power supply. I don't like that. I rather see a T upstream feeding both power supplies with equal length wiring (to be really anal about it ).
I am puzzled by selling an amp with those giant speaker biding posts but with skinny wires on the inside. I would shorten those wires and make them beefier.
There are also fine wires flapping in the wind for different power supply feeds for trigger circuit and such. They cross the main power supply wiring which could subject them to noise pick up.
Conclusions
Much of the heavy lifting is performed thankfully by the Hypex and Purifi modules. The assembler's job is to put these together in a safe and performant manner. I don't think that has been done here. Suggest a clean up path with input from community here to improve the design without much cost hit. As a minimum, the mains wiring needs to be tied down and away from heat sinks. Yes, chances of a short is one in a million. But do you want to be that one in the million?
------------
As always, questions, comments, recommendations, etc. are welcome.
Appreciate any donations using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
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