For a price a good choice. Just don't get it with power supply. It seem to be underpowered, mine turned into a half brick after 5 hours. I didn't push it hard for long, only during the first few minutes of testing in which I noticed, it was overloaded at times. After that it was driven @steady load @10-15 Watts peak. When died, I replaced it with the old Meanwell S100-24, it never do activate protection, my bookshelf speakers do complain before it happen. You should get 150W version to have a margin.
To be honest, with a little bit of perspective the FX502S PRO is great for its price. I am getting one.
For a price a good choice. Just don't get it with power supply. It seem to be underpowered, mine turned into a half brick after 5 hours. I didn't push it hard for long, only during the first few minutes of testing in which I noticed, it was overloaded at times. After that it was driven @steady load @10-15 Watts peak. When died, I replaced it with the old Meanwell S100-24, it never do activate protection, my bookshelf speakers do complain before it happen. You should get 150W version to have a margin.
There is a lot of clean power from this amp. There is no jaw dropping on the beginning, but it sounds really good, natural, bass is very tight and fast. Female vocals, guitars, drums sound perfect. Everything I do throw in sounds good. However I generally do agree with comments @vert. It is not about sibilants though, I have it well controlled on Polk Audio Rt3, but a long listening experience. When listening to the complex material like choir, I am sensitive to the specific distortions in the 5-7kHz range, it cause a fatigue. To be clear, young people I asked for the opinion don't see a problem.
There is a design fault which makes the amp sound the best at the volume set to 9 to 11 a' clock. It is something like the impedance matching problem with TPA. Turning the volume up beyond 2'a clock can trigger protection as Amir has indicated. It is not what would turn me off from purchasing this amp, many other attributes speak for.
The amp seem to be sensitive to speakers. It works well on polks, but Wharfedale EVO2-8 dominate with high frequency. The other amp (read below) control speakers much more even.
So, now there is other thing as promised. For a price below $120 from Aliexpress you can have a complete stereo amp with built-in PSU that is performing a class higher than FX audio. It it is now placed on my desk, disregarding any safety standards, no enclosure, just a PC-board, driven by the Topping D30 directly (there is no pot, as the amp input impedance strongly changes vs. frequency). Any pot would reduce high frequencies.
I planned to purchase two IcePower 50AX2 BTL, but the seller didn't know which version they sell and SE stereo version is not convertible to BTL, so I settled on the 125AX2 that can work either in SE or BTL mode. I do encourage Amir to test these amp modules. I am very happy from the IcePower. Still I hear distortion in 5-7kHz like in other D-Class, but to the much lesser degree. However it is a topic for another thread.
View attachment 29504
FX502SPRO is behind.
Thanks, I saw it. It would be interesting to see measurements of the amp module alone. There is also Amir's review of PS Audio Sprout 100 which use in my opinion the same module and results are different.You have now my attention. How do you control the volume then?
By the way, Amir already reviewed the Yamaha WAX50 (or something) with the 125ASX2.
Allo Volt+ and Allo Volt+ D are TPA3118 amps that might be able to outperform FX502S Pro.
When Allo.com releases TPA3255 amps, I will buy one.
Many people are perfectly happy with their FX502S amps - despite the objective metrics. So many people love to put tubes in their signal path, despite all the measurements showing that tubes just add relatively high amounts of distortion
Apparently "high fidelity" is below 0.1% distortion, which -60dB. The FX audio unit easily surpasses that requirement.
I'm not worried about its objective metrics when it is working well. He reported that it tended to randomly produce extreme amounts of distortion that he could hear with his ears. Maybe, he received a defective unit. Maybe, the model itself is faulty.
Plus, the fact that protection circuit kicks in beyond 2'o clock due to design error makes me question its quality.
I also question lifespan of condensers on FX502S Pro. Allo uses high quality components including high quality condensers on its amplifier boards.
It's possible that Allo Volt+ which costs 40 USD on amazon.com surpasses or matches FX502S Pro because Allo squeezed more performance out of TPA3118 through tuning than TI engineers did.
I also suspect that TPA3255 version of Allo Volt+ may not cost more than 70 USD which is still pretty cheap. No-name chinese TPA3255 amps are being sold at about 45~46 USD on aliexpress.com.
Perhaps, I can be satisfied with TPA3116/TPA3118 amps that do not have any defects in design as long as they provide my speakers with enough power.
The first part of this is misleading, because the $40 item on Amazon is not a turnkey, usable amp. Its a bare board, no enclosure, no power supply, screw in speaker terminals, not even a knob on the volume control
The 3E Audio TPA325x boards are all at least $70 for a bare board, and they, like the expected Allo amp, are based on the TI reference design. If Allo puts all their tricks into the board and specs good parts, how are they going to sell it for that much cheaper than another Chinese manufacturer who is also building a clone of the TI reference design?
That is about 2x the cost of the fx502s pro
Which power supply do you recommend for FX502S Pro?
- A 24V 4A power supply that comes with https://www.aliexpress.com/item/32857433809.html
- Mean Well GST90A24-P1M 24V 3.75
If you are going to buy a TI TPA3250 TPA3251 TPA3255 series amplifier, I would recommend the following products.
The higher the power supply voltage, the better the sound quality.I'm attracted to ABGN Hot-Tpa3255 because it is more powerful and uses a more recent amp chipset. What kinds of power supply do you recommend for this? I want to drive Eltax Monitor 1. The seller recommends 30V 6A although I may want more power.
I'm using 32V / 5A or 30V / 10A.