Not. This is Texas Instrument data.
At a frequency of 1 kHz. most inductors work in almost the same way. It makes no sense to compare them at this frequency.
The difference manifests itself at other frequencies and at a power of more than 1 Watt ...
At a frequency of 1 kHz. most inductors work in almost the same way. It makes no sense to compare them at this frequency.
The difference manifests itself at other frequencies and at a power of more than 1 Watt ...
Attachments
Last edited:
Without a lot of closed loop feedback around the inductor, there is still unresolved hysteresis distortion, so the inductor matters for the typical TPA3255 application: Blog - PURIFI
The SAGAMI 7G14J-100M-R is pretty decent and the saturation current is moderately high. The Coilcraft AGP2923 & VER2923 has a higher saturation current and very flat L vs I curve.
By the way, JLesterP used the 6.8uH shielded version (was changed to 10uH later, due to delivery issues) VER2923 / AGP2923 inductor on his TPA3255 Sylph200 design:TPA3255 - all about DIY, Discussion, Design etc.
Last edited:
D
Deleted member 148505
Agreed, it should be a high performance amp first and good sounding without PFFB. Then decide to put PFFB after the fact.
3e-audio 3255 feedback
Hello,
just finished to mount Pffb on 3e-audio 3255.
First power on red light and white led lights up(fault).
After several attempts to power on, red led lights up and after few seconds turns off.
Any idea?
My friend told me 3255 died due to in my configuration opamp bypassed .
But i cannot belive.
Anybody mounted Pffb on 3e-audio?
Hello,
just finished to mount Pffb on 3e-audio 3255.
First power on red light and white led lights up(fault).
After several attempts to power on, red led lights up and after few seconds turns off.
Any idea?
My friend told me 3255 died due to in my configuration opamp bypassed .
But i cannot belive.
Anybody mounted Pffb on 3e-audio?
I did the PFFB conversion on the previous version of the board (opamps soldered onto PCB). It really didn't make it sound much better. It played fine for awhile (a few days) but then the fault light just stayed on one time I turned it on and that was it. I couldn't get it to work again. I bought the newer version and decided not to try the PFFB mod again.It does sound fine without it.
Just my opinion..
Cheers
Use TPA3255 for its intended purpose and there will be no questions about the inductors used. When used in PBTL mode, it doesn't really matter what kind of inductors you have.
For good stereo with low distortion (if there are passive filters in the speaker), you must use two TPA3255 microcircuits in PBTL mode. Even the cheapest filters from SAGAMI (7G14J-100M-R) provide very little signal distortion. Perhaps the best.
Distortion plots showing only 1 kHz frequency. are not the main ones.
This is a scam of "suckers". "Ponty for visitors" (Russian slang).
Естественно, я не пишу для колонок с импедансом 2 - 4 Ом. (автомобильная версия).
Пишу для обычных динамиков, качественное воспроизведение звука с высокой верностью - 8 - 16 Ом. (иногда больше).
Take a look here, it is interesting (I already shared it a few pages back) :
TPA3255 / TPA3251 / TPA3245 universel - un pour tous - #360customs
Your picture is not scalable, it is very small ... The letters are hard to read.
I've seen her before. There is nothing special there.
This data is for low impedance loads that are not relevant to real loudspeakers - with high sound fidelity ...
Further, the data was taken at a frequency of 1 kHz, which cannot be used to judge the quality in the entire frequency band, at different power levels.
I'm already tired of your posts with photos that cover the entire page. I'm tired of flipping through your photos, because they do not carry any practical measurements or data. Only black and white carpet. Already dazzling in the eyes. It looks like spam.
I think that you are very far from the real acoustics of the premises, judging by your speakers and room.
I've seen her before. There is nothing special there.
This data is for low impedance loads that are not relevant to real loudspeakers - with high sound fidelity ...
Further, the data was taken at a frequency of 1 kHz, which cannot be used to judge the quality in the entire frequency band, at different power levels.
I'm already tired of your posts with photos that cover the entire page. I'm tired of flipping through your photos, because they do not carry any practical measurements or data. Only black and white carpet. Already dazzling in the eyes. It looks like spam.
I think that you are very far from the real acoustics of the premises, judging by your speakers and room.
Last edited:
That was just to share ) You will find the scalable picture here :
TPA3255 / TPA3251 / TPA3245 universel - un pour tous - #360customs
Anyway, thanks for your feedback
I am using this amplifier for a 3-way speaker system.
I connected a supply voltage of more than 40 volts. The circuit worked in test mode. Then I use it with a supply voltage of 36 volts. Less heating.
I'm using a balanced output source, so I removed the op amps. Added voltage dividers to reduce the input signal in level from ± 6 Volts to ± 3.9 Volts (according to the datasheet).
Learn how to properly attach your photos to the forum. Don't obscure the pages with your carpets ...
I mounted pffb on 3e audio 3255,
but using not smd components.
A little ugly, but functional and easier,
also to remove.
Working fine, gain quite reduced.
There's an issue, for single end input use
just one C_op each channel, on the first opamp,
instead of two.
The diagram of 3e audio is very similar of the TI EVM.
In my opinion, much of the harshness is due
to the preamplifier circuit (op amps, capacitors);
I was wondering, is there an easy way to skip op amps in single end input?
Last edited: