TPA3250 somebody is listening?

[chermann]

strange soudn but nice to listen...try it complete 😉

titel
sketch #1
album
RIOS
interprets
Dino Saluzzi, Anthony Cox..

album
Wesseltoft Schwarz Duo (yellow cover ..)
Duo - Bugge Wesseltoft, Henrik Schwarz: Amazon.de: Musik


have fun

 

[chermann]

other psu with less voltage 15V

for testing i can try a psu with less voltage but up to 16 ampere power.
is there any problem with the implementet regulator?

.LDO LM317

 

[impuls60]

That LDO's job is to lower to voltage into the op amps. With lower voltage (less than 24V)the regulator wont be able to proper regulate the voltage, so any noise from the psu will reach the op amps. Thats why you need a quality psu for lower voltage. At higher than 24V the regulater will step down the voltage for the op amps. The only issue mentioned earlier is that the regulator maybe lacks cooling for 30V+.All this has been discussed earlier in the tread.

 

[chermann]

That LDO's job is to lower to voltage into the op amps. With lower voltage (less than 24V)the regulator wont be able to proper regulate the voltage, so any noise from the psu will reach the op amps. Thats why you need a quality psu for lower voltage. At higher than 24V the regulater will step down the voltage for the op amps. The only issue mentioned earlier is that the regulator maybe lacks cooling for 30V+.All this has been discussed earlier in the tread.

thx impulse60

have to search and read....

 

[michael crump]

Sounds like that one I've read about being "Audiophile" quality with a .0005% THD + N. around $160 bucks. 70 +70 watts. Nice, very nice but I can't afford it. Maybe it was 3251.

 

[FauxFrench]

Sounds like that one I've read about being "Audiophile" quality with a .0005% THD + N. around $160 bucks. 70 +70 watts. Nice, very nice but I can't afford it. Maybe it was 3251.

Could well have been TPA3251 (8 Ohm speakers) but then you have a zero too much (.0005% -> .005% THD).

 

[chermann]

..fx502 pro V5

Hi again

i burn in the amp1 and the other amp i opened and changed just the opamp.

old NE5532
new BB 2134

on the pic you can see the version number , its V05 from 20170502. it looks well soldered and e.g. the rubycon 1800/35 are marked we the "K" on the top and thats no fake ! its real.
the other components i do not check.

actually the amp 2 with BB2134 is burning in for the next days.
i will compare it to the original amp (amp1) just with changing the opamps

chris

 

[strongbow60]

Anyone else have a problem with popping noise coming from the amplifier? It's not loud but it repeats every 20-30 seconds for about 1-2 seconds. Could it be a faulty capacitor?

 

[chermann]

Anyone else have a problem with popping noise coming from the amplifier? It's not loud but it repeats every 20-30 seconds for about 1-2 seconds. Could it be a faulty capacitor?

if its at different speakers the same popping, then i guess yes.
1 did you change the power supply?
2 does this happend at every volume?

if yes then its the amp, i guess

 

[swank42]

Hi again

i burn in the amp1 and the other amp i opened and changed just the opamp.

old NE5532
new BB 2134

on the pic you can see the version number , its V05 from 20170502. it looks well soldered and e.g. the rubycon 1800/35 are marked we the "K" on the top and thats no fake ! its real.
the other components i do not check.

actually the amp 2 with BB2134 is burning in for the next days.
i will compare it to the original amp (amp1) just with changing the opamps

chris

Based on the pictures above, is there a new revision to the FX502SPRO?

White PCB? v5 instead of v3?

 

[chermann]

Based on the pictures above, is there a new revision to the FX502SPRO?

White PCB? v5 instead of v3?

i did not open the Amp1 so i guess a have 2 similar amps.
the sensitivity at the volume knob is the same = very sensitive

 

[swank42]

Has anyone compared the layouts and chips?

I have one of the earlier ones, having bought this back when the thread was started. It has a blue PCB. I have a second one coming (thanks to the AliExpress sale recently I got it for about $45). I'm excited to see if it has a different PCB.

 

[chermann]

..NE5532 Fake..

concerning the original implemented op amps i found an interesting thread

NE5532 72AGRYM...?


post #13


Fake TL082 are actually a cheaper model (?)

 

[swank42]

I ordered some LME49720NA chips, are these the correct ones?
GENUINE LME49720NA Texas Instruments Dual OpAmp Audiophile; TI LME49720 DIP-8 | eBay

Two things:

Is there an orientation to the chips? Can the just be plugged in one way?

Do others agree that the sound quality is improved with these OpAmps over the stock NE5532?

 

[chermann]

I ordered some LME49720NA chips, are these the correct ones?
GENUINE LME49720NA Texas Instruments Dual OpAmp Audiophile; TI LME49720 DIP-8 | eBay

Two things:

Is there an orientation to the chips? Can the just be plugged in one way?

Do others agree that the sound quality is improved with these OpAmps over the stock NE5532?

Hi

I personally do not trust an ebay seller . i bought my BB Opa 2134 (DIP -8 housing.....so easy to change !) about 3,19 Euro at a "normal" store - Conrad Electronic". because i want to have it fast for compare it with the original.
if you use this big forum : you will find different ideas to get better SQ or not.

if i remember right " forstgump" is testing his different opamps bought from some ebay seller - and he gets strange measurements.
Is this a fake LM4562NA?





Result:
my first comparission between the burn in opa2134 in my amp2 and the original amp1 with NE 5532 "fake"....is YES ---> better SQ (after approx. 30 hours burn in)



cu
chris

 

[zek]

Is there an orientation to the chips? Can the just be plugged in one way?

Yes, there is some mark on first leg, because you can plag it in both ways by mistake.

 

[swank42]

Has anyone compared the layouts and chips?

I have one of the earlier ones, having bought this back when the thread was started. It has a blue PCB. I have a second one coming (thanks to the AliExpress sale recently I got it for about $45). I'm excited to see if it has a different PCB.

I got my second FX502SPRO tonight. It too has a blue PCB that says
Rev 3
2017/2/17

Has anyone else gotten a white V5 board and is there any difference?

 

[chermann]

Yes, there is some mark on first leg, because you can plag it in both ways by mistake.

thanks ZEK...i forgot to explain.



on the left side of this chip you will find a "mark" , normalli a half circle. if you keep this on the left side the first pin on the left side below starts to count counter clockwise.

8-7-6-5
)
1-2-3-4



dip8 counting - Google Search


sorry i cannot compare the white with the blue pcb....no idea


chris

 

[chermann]

I've just started modding a TPA3255 board (from Taobao) - the chip looks very similar to the 3250 except for the maximum voltage rating.

The mods I've found making a difference so far as PSU-related. Looks like the FX502 has a buck regulator (the 5pin device) which will generate plenty of noise. Hence filtering out its noise pays dividends in SQ. I also just found out that more decoupling on the TPA's analog regulator output (pin14) improves dynamics and transparency. I started off with 470uF (put in parallel with the 1uF the application shows) and I've since moved up to 1800uF.

I've yet to try upgrading the opamps (TL072 on mine) but I may try that at some stage, along with biassing the outputs into classA with a current source.

I'm documenting the mods here : TPA3255 - all about DIY, Discussion, Design etc.

Hi

sorry to pump up this ....you mentoined the post in the thread TPA3255 on page 60 #591???


thx
chris

 

[abraxalito]

Hi chris - sorry, I can't quite get your question here. That's a place where I talked about my mods to my TPA3255 board yes. I figured what worked for 3255 would likely also work for 3250.