TPA3250 somebody is listening?

I'm new and greet everyone

Hello everyone
After reading all 66 pages a FXAUDIO FX502SPRO TPA3250 ordered + 2x LME49720NA .....
I have to say that the sound is very good ....;)
Moodeaudio is installed.....:)
 

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Thanks to this thread, I went ahead and modified my Amp as per posts by @chermann and @irribeo.

I replaced the LM317 resistor with another 0805 surface mount 3k6 and soldered the cap across it - as shown in pic 1. Pic 2 shows the extra heatsink and bypass caps in place. I cut a rectangle from an old (dead) PC PSU heatsink that was the perfect depth, then glued it in place with heatsink epoxy sandwiched with a silicone transistor heatsink pad to isolate it from the PCB. I cut around an existing threaded hole in the heatsink and used that to attach to the bottom of the case (took some very careful measuring to get the hole in the case correctly!).

Anyway, all works now, though not had time to do any real listening tests. Thanks again to all.

Hi all, are these component modifications/swaps advised for everyone using the bundled PSU? I'm running some Dali Suite 2.5 4 Ohm speakers, and it sounds quite ok, and I dont have any problems or error lights.
 
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Hi all, are these component modifications/swaps advised for everyone using the bundled PSU? I'm running some Dali Suite 2.5 4 Ohm speakers, and it sounds quite ok, and I dont have any problems or error lights.



hi peter


my personal target for this amp is to use the original psu.= 24V

internal regulator is not correct implemented by fx audio because the setup of lm317 is set to 22,7V and so the regulator is not working. The datasheet requires 3V differents about input and output of the lm317. so the regulator is not working correctly and you might get the "noise" of the psu into your amp.




yes no problems with error light- error light comes if the impedance gets lower than 4 ohms / or if you get undervoltage = psu get down. i tred a test with 2 ohms load...not possible with this psu.



chris
 
Hello everyone
After reading all 66 pages a FXAUDIO FX502SPRO TPA3250 ordered + 2x LME49720NA .....
I have to say that the sound is very good ....;)
Moodeaudio is installed.....:)

Howdy Cardone, I also bought some LME49720NA for my FX502SPRO

For the sake of my authenticity verification, how does your LME49720NA look like?

Top# Element14's or Bottom# RS-online's

694987d1533260053-class-amp-transparent-neutral-monitoring-music-production-10-lm49720-asus-xonar-essence-jpg
 

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Hello,

I've been reading a lot of good things about Class-D amps. My current TV/audio configuration is TV box / BluRay player / PC or smartphone into the toslink / coax / usb inputs of a DAC, to a mid-2000s 35W Teac A-H300 analog amp.

The DAC (by Audiophonics) is a recent one and a solid piece of equipment. The sound from that little system is already very good.

But I was thinking replacing the amp with a Class D might bring an improvement in sound quality for not much financial outlay. The FX-Audio FX502SPRO seems among the best candidates.

My first question was how much of a step up in SQ can be expected by replacing a decently made, but by no means upscale unit such as my Teac with a Class D amp? Is it anything like a dramatic improvement or something more subtle?

My other question had to do with an opinion I've seen time and again on some other, often rather intolerant forums, that "full FDA" configurations, e.g. using an SMSL AD18 to do the job of DAC and amplification, are better than having a separate DAC and Class D amp, because the latter adds an unnecessary conversion step, D/A back to A/D, outside the digital realm, that might degrade the sound. Truth or BS?
 
Hi Vertig

the amp is actually to buy at amazon prime 66 euros.
with power supply

i do not have experiance with FDA so no comment.

the FX502Spro is a really very good sounding amp ...i compare this with old more powerful amps . if you want to mod - here in this thread you are right :D

i propose to read thru this thread and read about some nice informations.
mod is not necessary - first step could be changing the opamp as forestsgump and cardone.


actually i am working on tpa3255...but i promise --> if i am finishend with my planned step i will continue with FX502Spro ...:cool:

chris
 
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Hi Vertig

the amp is actually to buy at amazon prime 66 euros.
with power supply

i do not have experiance with FDA so no comment.

the FX502Spro is a really very good sounding amp ...i compare this with old more powerful amps . if you want to mod - here in this thread you are right :D

i propose to read thru this thread and read about some nice informations.
mod is not necessary - first step could be changing the opamp as forestsgump and cardone.


actually i am working on tpa3255...but i promise --> if i am finishend with my planned step i will continue with FX502Spro ...:cool:

chris

Thanks ; ) Happy to know it compares favorably with older amps. More power and potentially better sound with 1/5 of the footprint and power consumption is tempting.
 
Thanks ; ) Happy to know it compares favorably with older amps. More power and potentially better sound with 1/5 of the footprint and power consumption is tempting.


please do not miss understand me. i looked years ago always at power and nice and big amp and everything - commercial "programmed" - since i am doing more DIY i learned that power is nothing without adaption (e.g. output filter, settings...).
my first diy taks was to connect a smal full range speaker and push more power in to it. at 4 Watt 400- 3khz you will run out of your lab;):D

for listening rooms you do not need hundred of watts.
 
...
the FX502Spro is a really very good sounding amp ..
but i promise --> if i am finishend with my planned step i will continue with FX502Spro ...:cool:chris

Always enjoyed reading Chris sharing & "conversing" about his journey modding into "ultimate" audio gear here. Look fwd to hear your FX502Spro mod journey:cool:

..
that "full FDA" configurations, e.g. using an SMSL AD18 to do the job of DAC and amplification, are better than having a separate DAC and Class D amp, because the latter adds an unnecessary conversion step, D/A back to A/D, outside the digital realm, that might degrade the sound. Truth or BS?

Happen to purchase FX502Spro followed-by Alientek D8... probably some would wonder why?

Have being doing some search on Class D, T-Amp TA2020, TPA3116, TDA7498E, SMSL SA-36A, etc...landed on FX502Spro becos it is moderate powered TPA325x family member of the latest Class D clean path low THD.

Listening FX502Spro is a pleasure to remember, though if near field - very ever-slight backgrd noise.

Though thought am done. . . just couple months later, as I consider use case - mainly Classics + Pop + Jazz + alittle movie watching. These are digital sources - PCM/DSD, or internet/network streaming, None analog; if I use FX502Spro, I wld need to addon an DAC, addon optical, addon USB audio, lots of interconnect & PSU.

This means increase resources, real-estate, time for fine-tuning, instead avoiding it, took on another crazy research towards a streamlined digital solution, namely FDA . Came across SMSL-SA50 plus, AD18, Q5 Pro, FX D802, I.AM.D V200 & finally Alientek D8 ~ is what I want:

D8: STA328 PWM direct digital open-loop, built-in XMOS USB/Optical asynchronous input, using WM8805 for S/PDIF recovered clock having low intrinsic jitter of 50 ps RMS. (open-loop are non-differential - non-compensating, could be a concern for some)

Sufficient powered, Digital PWM ie. non-DAC path, low jitter reclock Digital path via USB/Optical, accepts PCM384/DSD128. Plus - Dac headphone output, Minus - dont come with Wifi & poor analog due to preamp uses onboard nosiy smps - (which have no use) & bluetooth-aptx-hd -is gimmicky . Just need add wifi streamer - an Alexa or Google Assist - to complete the picture (along with D8, D8's PSU, speakers cable, speakers, usb cable/optical cable)

Matches exactly what I looking for - one that is carefully though, features reflect much-thought - that I care & not overly-design, reasonable quality, compact yet affordable.

How does D8 sound compared with FX502Spro?
Honesty I don't have a simple answer - fortunately enough to own only these 2 crafts :D

They are very close - FX502Spro comes with Op-amp NE5532 sounded fine, even bef. drop-in LME49720, while D8 is assured of unadulterated neutral sound at the same time rewards respectable system without "audiophile" footprint - both are fast tight, detail and pleasure to listen for hours at a stretch.

Technically speaking:
Don't we all know most speakers are analog -so the final stage in FDA has to be DAC. Personally I still believe is way better than littering early audio path
with DAC, Opamps, interconnect everywhere - mind you - we are toying with analog signals here much care is needed- maybe is industry purpose for over-selling.

Anyway, whether you are a diy, or audio user, aint all here for the purpose hear the music, hope 1 day we can finally get over technical talk?!? :D

Do I still keep FX502Spro? Yes - maybe 1 day I heard enough of D8, I switch back to FX502Spro having LME49720 for more comparison (or follow Chris modding on FX502Spro). Each to his own ~ till then adios! :D
 
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forestsgump, thanks, that is immensely helpful.
Interesting to note you don't report a dramatic change in quality from going full FDA.
Interestingly also my needs are similar to yours.
Thing is, my DAC already has all necessary inputs - optical, coax, usb, all well implemented. From what you say, SQ should be great, despite the added interconnect.
OTOH, the added headphone input on the D8 is a plus. I could sell the DAC and just get a D8.
Decisions, decisions.
Today I discovered some articles from 2015 by some French audiophiles about mostly the FXAudio 802. The reviews from such guys, who are used multi-thousand euro systems, were a jaw-dropping read. what they said basically was, FDAs were a one-way sonic tickets, there was no going back to analog after several weeks of testing the 802. They even tested it with some ultra-expensive, esoteric speakers and were equally convinced. Those articles later spawned hundreds of posts on some forums. Stunning stuff, really.
 
vertig, be careful - it seems your expectations are very high, so I must tell you that in my experience the Alientek D8 is good, but not great. Please read about my recent listening test -
https://www.diyaudio.com/forums/class-d/322666-ta2020-vs-tpa3118-vs-tda8932-comparison.html#post5539856
Using a decent (but not great) CD player as source, both my TA2020 amp and dual-mono TPA3118 amps beat the D8 for SQ. And I'm expecting the new TPA325x amps to beat my TA2020 and TPA3118, but I've read that the FX502SPRO is a less than optimal implementation, so I will be building my own TPA3250 amp using the EVM board.

Regarding those French forums - I think you're talking about HCFR Mag - Le site du HomeCinema FRancophone - yes, I read that stuff too, but I don't read it the same way as you! The amps which attract high praise on that forum are the higher priced examples - like the D.Sound D310, and of course the Lyngdorf. As I read it they seem to consider the budget priced FX-Audio D802 as something of a taste of what FDA can be.

So do I recommend against the D8? No. At $100, I consider it the best value hifi entry-point for amplifier/DAC, for people whose audio sources are exclusively digital.

But at the $200 price point, there's a noticeable step up in SQ by getting a well regarded "budget" class D amp + DAC
- something like the Breeze Audio TPA3116 amp (approx $50 inc power supply) + Sabaj DA3 DAC ($120). This DAC is USB only. If you need s/pdif as well I would suggest something like the HiFime UDA18 DAC ($160) instead of the Sabaj. Now the price-point has jumped a little over $200.

Want a slightly better class D amp - maybe the FX502SPRO instead of the Breeze Audio. Now the price-point is $250 total.

So where does this all sit in relation to your situation? Google tells me your Teac A-H300 is a good amp - maybe as good as the NAD C316BEE? Wow. If so, I would be surprised (or shocked) if your amp + decent quality DAC does not beat the Alientek D8. Which raises the question; what is your DAC? I had a look at the Audiophonics site and I see they have some very good DAC's - but I hope you don't have that 38 Euro s/pdif converter they sell !! That would certainly be the weak link in your audio chain.
Maybe you just need a DAC upgrade?

And rather than speculate about all of this, it would really be best to do a home listening test, yourself, with a D8. If you cannot find a seller who will loan one out, you could just buy one, then sell it you're not happy with it. Or do what I do - keep it and just use it for TV/video.

But please tell us exactly which DAC you have.