JL ELectronics Sylph-D200 Amplifier Module Review

[sarumbear]

Where did you find an assembled amp with these modules for 350$? Amir say the module only is 130$ to 170$... It doesn't add up at all. even for the amp under review, now imagine with a power supply able to give 300W/ch. You are talking about the chip or the module under test?

I’m commenting on a possible DIY kit amplifier.

 

[Bruce Morgen]

Why a separate "soft start" board when (e.g.) the Aiyima folks where able to eliminate the TPA3255's power-on popping sound via a change on their amp board? Without that extra board, will this module have that popping when power is applied from a typical external power brick or SMPS?

 

[PeteL]

I’m commenting on a possible DIY kit amplifier.

Ok, but using these modules or other implementations of the chip? For reference one channel of NC500 is 104$(the cheapest Ncore that don't include a PSU), a stereo amp using NC500 is At least 1000$ (and honestly DIY is rarely much cheaper than assembled in this line of builders amps). My DIY NC500 implementation costed me considerably more than 1000$ So how do you achieve this number?

 

[Helicopter]

Agree. I have been toying with this for a bit. I am thinking 150 for module, 150 for a good SMPS, 25 for soft start, 35 for connectors and wires and stuff, and then 25-250 for a case depending on how nice, so $400-600. Not really cheap.

Buckeye nc252mp is $500 and you don't have to assemble it.

Still, I am really excited to see this level of performance in a module based on this chip.

 

[Newman]

Where do the PSU and soft start modules come from?

 

[AudioJester]

I think best value for money class D may be UCD180 and UCD400. With appropriate speakers you can hardly pinpoint any "sonic" differences compared to NC500 and Purifi.

 

[xarkkon]

Nice layout on the PCBs and the chassis assembly. What kind of extra expense is there for adding a case and terminations for input and output?

Is that something that might be available as a option in the future @jlesterp ?

count me in for that too! would love to have an all-in-one kit to put together. the case that Amir received looks pretty nice for a DIY kit

@jlesterp congrats on a the great review / product!

 

[PeteL]

Agree. I have been toying with this for a bit. I am thinking 150 for module, 150 for a good SMPS, 25 for soft start, 35 for connectors and wires and stuff, and then 25-250 for a case depending on how nice, so $400-600. Not really cheap.

Buckeye nc252mp is $500 and you don't have to assemble it.

Still, I am really excited to see this level of performance in a module based on this chip.

Right, and it’s if you got the right tools for cutouts… Finding the chassis that have all the right holes at the right place is possible? Labelling, all that stuff, DIY always seems like a fun economical thing but… Unless of course you get a full kit with everything sorted, but there’s a steep markup for this too, nothing is free. (my time neither)

 

[Bruce Morgen]

There's a rumor afoot that some entry level Class D modules from IcePower are actually built around a hidden and/or rebranded TPA3255. Just a rumor, mind you -- but not an outlandish one.

 

[JohnYang1997]

There's a rumor afoot that some entry level Class D modules from IcePower are actually built around a hidden and/or rebranded TPA3255. Just a rumor, mind you -- but not an outlandish one.

Even it's just a rumor...Where is the rumor come from?

 

[tomtoo]

I wonder when we will see the first implementations with two tpa3255 in pbtl mode.


More fun.....

 

[Bruce Morgen]

Even it's just a rumor...Where is the rumor come from?

Hi, John -- I have no clue where it originated, but I read it in a U-Toob thread from a someone who appeared to be a fairly level-headed audio hobbyist with a strong interest in Class D amplification.

 

[maxxevv]

I wonder when we will see the first implementations with two tpa3255 in pbtl mode.


More fun.....

You mean 2 channel into 1 mono 'bridging' mode ?

@3eaudio already has such a board out for quite a while. Believe its 400+W output per mono module if I remember correctly.

 

[amirm]

Where do the PSU and soft start modules come from?

They are off-the-shelf products. Power supply is the Connexelectronic's SMPS300RS. I don't know where the soft start came from.

 

[tomtoo]

You mean 2 channel into 1 mono 'bridging' mode ?

@3eaudio already has such a board out for quite a while. Believe its 400+W output per mono module if I remember correctly.

Exactly. Like to see how they measure. I mean thats than power for the grown up.
Headroom is your friend.

 

[Toku]

Why a separate "soft start" board when (e.g.) the Aiyima folks where able to eliminate the TPA3255's power-on popping sound via a change on their amp board? Without that extra board, will this module have that popping when power is applied from a typical external power brick or SMPS?

The pop noise prevention circuit is built in this amplifier board. The soft start module is for reducing the surge current when the power is turned on, and at the same time doubles as a power switch. ON / OFF is controlled by the power switch on the panel. It has nothing to do with pop noise prevention.

 

[SylphAudio]

Hi Amir, thank you very much for the review! Much respect to you and your audiosciencereview team.

The design goal of this module is to get TPA3255 EVM level price/performance but with a signicantly smaller footprint. We also added PFFB implementation built-in, and uses better parts to achieve better sound quality.

We have sent the low power version so that we can achieve the highest 5W @ 4 ohms score, though it can get to 95dB or more SINAD rating if we have used a unity gain buffer and low impedance input resistors. High power version will get 1dB to 3dB lower SINAD score depending on configuration.

The input buffer has a 1.3x gain and uses OPA1656 opamps. Input impedance is 10Kohms so that it can accept most music input source.

It has 10x (20dB) SE, 5x (14dB) Balanced system gain, so that the module can produce a 20Vrms output out of 2Vrms SE / 4Vrms BAL input.

Getting clean 61W before clipping is desirable, it means you'll get consistent performance at different volume levels. Some amps only have 20W clean output and THD levels starts to rise after that.

Edit (Aug 6, 2021): we have fixed the early clipping issue by changing PFFB network values, PFFB and non-PFFB now have the same clipping output power.

Best regards,
Lester

 

[Bruce Morgen]

The pop noise prevention circuit is built in this amplifier board. The soft start module is for reducing the surge current when the power is turned on, and at the same time doubles as a power switch. ON / OFF is controlled by the power switch on the panel. It has nothing to do with pop noise prevention.

OK, so it's desirable but not essential, and may or may not extend the life of amp and/or SMPS boards?

 

[Bruce Morgen]

Lester

If was to use the board standalone with external power, would I need both 48VDC and 12VDC like the SMPS in the assembled amp Amir tested -- or is the 12VDC only for the soft-start board?

 

[SylphAudio]

How much does that fancy case cost?

Nice layout on the PCBs and the chassis assembly. What kind of extra expense is there for adding a case and terminations for input and output?

Is that something that might be available as a option in the future @jlesterp ?

Yes, I considered the layout of the chassis when I designed the module so that the wires of different purpose will not touch each other.

We bought the case for 75USD, any case with a 240mm * 320mm * 89mm dimensions will be enough, it can fit a meanwell supply. Minimum case height is 50mm.

Around 110USD should be set aside to get a decent chassis and accessories.
60USD for a decent power supply.

We have an EU partner to provide the complete / cased amplifier but it may take some time to go into production..

@jlesterp what do the measurements look like when paired with the 48V power supply?

5W at 4 ohms SINAD rating will be 1dB to 2dB lower, and various measurements will have a 2dB to 4dB lower performance.

Why did the company cheap out and didn’t send the amp with the beefier powesupply?

To showcase the SINAD rating hehe

If was to use the board standalone with external power, would I need both 48VDC and 12VDC like the SMPS in the assembled amp Amir tested -- or is the 12VDC only for the soft-start board?

You only need a single 48V power supply for this amplifier.