New Dual TPA3255 Module + PFFB / Fully differential / OP amps DIP8 @ Great price

[somebodyelse]

With this TPA3255 module, there's no need to ask the question, since there are two versions: one fully balanced and the other in SE mode )

I don't see how that answers the question about how they implemented 'fully balanced'

 

[daniboun]

I don't see how that answers the question about how they implemented 'fully balanced'

I suppose in the most consistent way, since there are two distinct versions... I don't have a better answer, unfortunately...

 

[frabor]

I read the topping b100 thread in diy audio, and if Topping cut corners in the implementation, you can assume that this manufacturere, at a much lower profit point, has done the same.

 

[daniboun]

I read the topping b100 thread in diy audio, and if Topping cut corners in the implementation, you can assume that this manufacturere, at a much lower profit point, has done the same.

I agree. Getting back to the B100, I don't see any particular cause for concern in its use, and the measurements seem to demonstrate that this amplifier is excellent despite these implementation imperfections

 

[Ruediger]

150w/8 300w/4 and 600w/2 ohm. Can it actually produce this?

Even with a 53v 10a psu not a chance at 600w.

I also suspect they write down these numbers without THD because it is already unusable high.

 

[somebodyelse]

I agree. Getting back to the B100, I don't see any particular cause for concern in its use, and the measurements seem to demonstrate that this amplifier is excellent despite these implementation imperfections

That's true for the RCA input if we ignore the anecdotal high failure rate. For the XLR input it's fine so long as you know not to use it with certain sources, which isn't documented (or wasn't - maybe they added since.) And to know whether your balanced source qualifies you need to know its output topology, which isn't usually documented because of the expectation that balanced inputs will be done properly. @pma wasn't aware of this when testing the B100 the first time so used the balanced input to get some CMRR benefit with a single ended source as you should be able to do with a balanced input. It missed the specified power output by a mile as you'd expect with only one side of the bridge driven. It was only after querying this with Topping that they said not to use it that way, and the retest using RCA input got close to specified performance.

 

[somebodyelse]

Even with a 53v 10a psu not a chance at 600w.

I also suspect they write down these numbers without THD because it is already unusable high.

Those numbers are chipset datasheet headline numbers, so at 10% THD. I think you need to be into clipping to get that much distortion out of it, so the PFFB can't help that figure. When I see them it makes me question whether the manufacturer has actually done any measurements, especially as in this market sector it's very rare for them to provide a proper datasheet for their implementation. On the other hand they couldn't compete in that market if they quoted a proper figure (if you could find agreement on which definition of power was 'proper') as competitors would still be quoting 600W. Almost everyone selling boards via eBay, Ali etc. quotes datasheet specs not measurements from their own implementation. That applies to amps, DACs and pretty much anything else. A select few will provide actual measurements in the description.

 

[daniboun]

Even with a 53v 10a psu not a chance at 600w.

Speaking of PSU, I made a great discovery at a rather reasonable price. (68€]

Check here (48V / 40A 2000W Single Rail version)

Nice PSU, built using an LLC resonant circuit design with high-quality components. Excellent circuit design. Compact, modern (pfc + llc). On the secondary side, A synchronous rectifier with 4 mosfets (150 v) instead of diodes. On the primary side, 2 transistors from magnachip: mdr60r037jf (37 mω, 70–80 a). The brain of the system is the kpe2592bsg chip—a specialized “2-in-1” combined controller that integrates control of the pfc (power factor corrector) and llc (resonant converter). The voltage range of 39–59.5 v is great.

 

[somebodyelse]

Is there any documentation available?

 

[daniboun]

Is there any documentation available?

Link to Spec

 

[somebodyelse]

So what's the relationship (if any) between NVVV and HLTNC? It can be hard with these boards and modules to find out whether similar ones share an OEM or whether someone just cloned another product. And whether they're using the same BOM, or even a consistent BOM. I'm just trying to judge how much of a lottery it is buying any of these.

 

[daniboun]

So what's the relationship (if any) between NVVV and HLTNC? It can be hard with these boards and modules to find out whether similar ones share an OEM or whether someone just cloned another product. And whether they're using the same BOM, or even a consistent BOM. I'm just trying to judge how much of a lottery it is buying any of these.

My bad I shared a bad link ) thanks just corrected

 

[somebodyelse]

My bad I shared a bad link ) thanks just corrected

Which link is bad? The Ali one is still for the NVVV branded item pictured in that post, and the documentation one still points to HLTNC.

 

[daniboun]

Which link is bad? The Ali one is still for the NVVV branded item pictured in that post, and the documentation one still points to HLTNC.

NVVV 2000W Industrial Switching Power Supply LSU2000-4840 | AC-DC Converter 48V 40A High Power Transformer with Smart Cooling Fan - Switch mode power supply, Switching power Supply manufacturer

Key Features High Power Density: Delivers a massive 1920W - 2000W output to drive heavy industrial machinery and telecommunications equipment. Intelligent

cnnvvv.com

 

[LSPhil]

Those numbers are chipset datasheet headline numbers, so at 10% THD. I think you need to be into clipping to get that much distortion out of it, so the PFFB can't help that figure. When I see them it makes me question whether the manufacturer has actually done any measurements, especially as in this market sector it's very rare for them to provide a proper datasheet for their implementation. On the other hand they couldn't compete in that market if they quoted a proper figure (if you could find agreement on which definition of power was 'proper') as competitors would still be quoting 600W. Almost everyone selling boards via eBay, Ali etc. quotes datasheet specs not measurements from their own implementation. That applies to amps, DACs and pretty much anything else. A select few will provide actual measurements in the description.

Texas Instruments’ datasheets are generally very solid and, in my experience, they are based on standardized measurement conditions that are clearly defined, which is exactly what makes them comparable in the first place. Of course, those are typically headline figures under specified THD limits and supply conditions, so they don’t always reflect a complete real-world system including PSU behavior, cabling, and load interaction.

I also did my own measurements for comparison using a practical setup. On the mains side I used a plug-in power meter, followed by an HRPG-600-48 power supply which can be switched via a small control line, and a ZK-3002 amplifier board configured for stereo operation. As a load I used four 50 W, 3.9 Ω resistors. With bass-heavy music content the power meter typically showed peaks around 170 W of input power, and in one case with “The Feeling of Bass” by Bassotronics it briefly reached about 190 W. When driving a clean 90 Hz sine wave, the system drew up to approximately 270 W from the wall.
From these observations, my conclusion is that with real musical content the average demand per channel at 4 Ω is significantly lower than the theoretical peak figures suggest, and in practice a well-designed 48 V / 500 W power supply is more than sufficient for this kind of use case. If needed, I can also provide photos of the setup and measurements.

 

[Roland68]

Speaking of PSU, I made a great discovery at a rather reasonable price. (68€]

Check here (48V / 40A 2000W Single Rail version)

Nice PSU, built using an LLC resonant circuit design with high-quality components. Excellent circuit design. Compact, modern (pfc + llc). On the secondary side, A synchronous rectifier with 4 mosfets (150 v) instead of diodes. On the primary side, 2 transistors from magnachip: mdr60r037jf (37 mω, 70–80 a). The brain of the system is the kpe2592bsg chip—a specialized “2-in-1” combined controller that integrates control of the pfc (power factor corrector) and llc (resonant converter). The voltage range of 39–59.5 v is great.


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I would really like to see a sustained load test of this—lasting at least 1 to 2 hours—especially given its dimensions.
I would also find measurements regarding the quality of the output very interesting.

 

[Roland68]

Texas Instruments’ datasheets are generally very solid and, in my experience, they are based on standardized measurement conditions that are clearly defined, which is exactly what makes them comparable in the first place. Of course, those are typically headline figures under specified THD limits and supply conditions, so they don’t always reflect a complete real-world system including PSU behavior, cabling, and load interaction.

I also did my own measurements for comparison using a practical setup. On the mains side I used a plug-in power meter, followed by an HRPG-600-48 power supply which can be switched via a small control line, and a ZK-3002 amplifier board configured for stereo operation. As a load I used four 50 W, 3.9 Ω resistors. With bass-heavy music content the power meter typically showed peaks around 170 W of input power, and in one case with “The Feeling of Bass” by Bassotronics it briefly reached about 190 W. When driving a clean 90 Hz sine wave, the system drew up to approximately 270 W from the wall.
From these observations, my conclusion is that with real musical content the average demand per channel at 4 Ω is significantly lower than the theoretical peak figures suggest, and in practice a well-designed 48 V / 500 W power supply is more than sufficient for this kind of use case. If needed, I can also provide photos of the setup and measurements.

The ZK-3002 amplifier board is unsuitable for a test of this kind—at least if that test is intended to yield meaningful results.
The PCB traces are too thin and narrow, and—most importantly—the output inductors are undersized and exhibit a significantly excessive resistance. The remaining limitations pale in comparison.

It would be interesting to see this test conducted using a 3E Audio A7se or the DIY TPA3255 board (model 260-2-29A).

 

[LSPhil]

The ZK-3002 amplifier board is unsuitable for a test of this kind—at least if that test is intended to yield meaningful results.
The PCB traces are too thin and narrow, and—most importantly—the output inductors are undersized and exhibit a significantly excessive resistance. The remaining limitations pale in comparison.

It would be interesting to see this test conducted using a 3E Audio A7se or the DIY TPA3255 board (model 260-2-29A).

That is an interesting claim, especially the part about the PCB traces and the output inductors. Have you actually tested or owned the ZK-3002 yourself, or are you judging it purely from photos and specifications?

I am asking because I have already compared it against other amplifier boards in the same enclosure and under the same power supply conditions, and the practical results were very similar. That is why I am somewhat skeptical that the limitations you mention are as severe in real-world use as they appear theoretically.

Which boards have you personally tested and compared directly? Have you measured them under sustained low-frequency load, or only looked at burst power and benchmark figures?

 

[Roland68]

That is an interesting claim, especially the part about the PCB traces and the output inductors. Have you actually tested or owned the ZK-3002 yourself, or are you judging it purely from photos and specifications?

I am asking because I have already compared it against other amplifier boards in the same enclosure and under the same power supply conditions, and the practical results were very similar. That is why I am somewhat skeptical that the limitations you mention are as severe in real-world use as they appear theoretically.

Which boards have you personally tested and compared directly? Have you measured them under sustained low-frequency load, or only looked at burst power and benchmark figures?

In a past project, we measured—among other things—the maximum output power at specific voltages and power supply ratings, as well as various power consumption figures.
The test subjects included various inexpensive TPA3255 boards, our own custom designs, and several EVA boards built specifically for the experiment.
The inductors installed on the cheap boards are, quite frankly, very low-quality. They feature a very low copper content and cheap core material, with a unit cost well under one euro per dual inductor. I am actually surprised that the negative impact isn't even more significant.
Furthermore, these inexpensive boards all feature only a basic copper plating.
You can find similar observations and measurement data in various threads on the DIY Audio forum.
Of course, in terms of price-to-performance ratio, the ZK-3002 boards—along with other budget-friendly TPA3255 boards—are simply unbeatable.

The inductors used on high-quality boards—such as those from 3E Audio, Topping, XRK Audio, etc.—cost more than twice the price of an entire ZK-3002 board (when purchased as a set of four at industrial wholesale rates); and there are very good reasons why those specific components are chosen.

The 3E Audio DIY boards are actually quite inexpensive—something you will truly appreciate if you ever build a board yourself using high-quality components.
After all, there are several excellent layouts and Gerber files available for this purpose, as well as the two TPA3255 PCBs offered by XRK Audio.

 

[Tell]

In a past project, we measured—among other things—the maximum output power at specific voltages and power supply ratings, as well as various power consumption figures.
The test subjects included various inexpensive TPA3255 boards, our own custom designs, and several EVA boards built specifically for the experiment.
The inductors installed on the cheap boards are, quite frankly, very low-quality. They feature a very low copper content and cheap core material, with a unit cost well under one euro per dual inductor. I am actually surprised that the negative impact isn't even more significant.
Furthermore, these inexpensive boards all feature only a basic copper plating.
You can find similar observations and measurement data in various threads on the DIY Audio forum.
Of course, in terms of price-to-performance ratio, the ZK-3002 boards—along with other budget-friendly TPA3255 boards—are simply unbeatable.

The inductors used on high-quality boards—such as those from 3E Audio, Topping, XRK Audio, etc.—cost more than twice the price of an entire ZK-3002 board (when purchased as a set of four at industrial wholesale rates); and there are very good reasons why those specific components are chosen.

The 3E Audio DIY boards are actually quite inexpensive—something you will truly appreciate if you ever build a board yourself using high-quality components.
After all, there are several excellent layouts and Gerber files available for this purpose, as well as the two TPA3255 PCBs offered by XRK Audio.

In the end, what's the actual difference between the cheap and more expensive comp? Audible sound quality? Objective sound quality? Longevity?