I have both boards and it all depends on what you are looking for...
Wiil it replace a mediocre amp, both amps are fine and will give you some good sound...
If it has to replace a top class musical amp...I would not go this way and keep that amp...
If you just want to check what class d amps can do today (that is why I bought a few) and like to experiment a bit...this is big fun...sometimes I am surprised how good these cheap amps can sound...but I have to be honest, this is not the ultimate amp I am looking for...(but as a tubeman I might be a little biased)
I would give the 3e-audio a plus because of the quality...@100 dollar
But the yj board is less than half that price and works/sound very similar...
If it is an experiment you are looking for, go for the cheapest...if class d and tpa3255 is good sounding for you in your system you could consider upgrading later...there will be other boards with tpa3255 the coming months...I think.[/QUOTE]
What is the best voltage for the yj boards. It states in the ebay description to use 50volts, most on here are using 40 volts, what do you think about going lower as i heard higher voltages can increase distortion, would lower voltages lower distortion and give better sound. 40 volts sounds like you are running the boards at the higher end of the rating
Thanks!
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A higher supply voltage generally increases headroom. So why should it increase distortion?
Best regards!
Best regards!
Due to increased quiescent current and higher dV/dt. The output stage is always switching up to full voltage, so your dV/dt is generally higher if ton/toff is constant. This will raise radiation as well which "may" induce noise/distortion/whatever in surrounding circuitry.
I heard class d's generally increase distortion quite dramatically at the top end of their voltage range.
So is there an ideal voltage for the tpa3255 or does it vary with implementation?
And has anyone tested the distortion at various voltages?
I have a power supply that can be set over a fair voltage range. It would be handy to know the ideal voltage for 3e Audio's tpa3255 containing EAUMT-0260-2-A.
How would one go about testing this?
And has anyone tested the distortion at various voltages?
I have a power supply that can be set over a fair voltage range. It would be handy to know the ideal voltage for 3e Audio's tpa3255 containing EAUMT-0260-2-A.
How would one go about testing this?
Often it seems to be a good idea to look at the data sheet of a certain D-chip.
There you can see distortion at different loads, supply voltage etc.
These firures should be achievable with any implementation that fits the circuit board the manufacturer designed.
There you can see distortion at different loads, supply voltage etc.
These firures should be achievable with any implementation that fits the circuit board the manufacturer designed.
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Do you have an opinion on the e3 audio 3255 vs B&O icepower 125asx2.
Have you heard anything or have a link to where this has been discussed, i can't find anything.
Thanks!
Have you heard anything or have a link to where this has been discussed, i can't find anything.
Thanks!
hi goodguys
No sorry...
You are posting the same in different threads....i see you are in flame with class D 😉
give us time to answer .....🙂
i personally start with TPA32xx (3116) chips and i am happy. actually i am not interested in invetigate different types .e.g.-ice-anaview- IRS2029..etc. to compare. yes....the class D amps are very interesting but now its too much for me to go a little bit deeper with all the kinds of class D.
my freinds are speakers builder (Disco M) and active in the german thread (...name = Herr der Ringe) and they do not care about amps and electronics...🙄
the only listening test i had was with some big anaview boards and it was on my speakers dissapointing for me -harsh - starnge, no controlled bass- bad voices and unreal instruments - at home my speakers/amps sounding fine - more like class AB/ A
but here are some guys with a lot of technical experience with different types and listening tests.
chris
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additionally....
You asking about the YJ TPA3255 or the 3e boards.
if you want to start and modding the amp - go for the cheap chinese bards - about 45 euros.
if you are not itnerested for modding --> start with better engineered development amps board then buy TI or the 3E boards.
i have a TPA3251 TI EVM board with the 50% discount (actually stopped)
so the price of a 3e board i very fair and as doc (developer) well done.
chris
You asking about the YJ TPA3255 or the 3e boards.
if you want to start and modding the amp - go for the cheap chinese bards - about 45 euros.
if you are not itnerested for modding --> start with better engineered development amps board then buy TI or the 3E boards.
i have a TPA3251 TI EVM board with the 50% discount (actually stopped)
so the price of a 3e board i very fair and as doc (developer) well done.
chris
As I didn't get any answer to a question that I've posted in another 3255 thread, I suspect that thread was not the proper one, and I dare to repeat it here:
as far as i understand is that the TI EVM board has a switch(Reset) and this set the power chip mute. you should be do this for power up or power off the amp. the SMPS status pin really do not help here.
so you have to use the switch or a circuit for the anti pop on / pop off.
chris
I plan transformer inputs with my 2 x 300 watts BTL configuration. Do I need two additional input resistors of, say, 10 kohms, in parallel with each of the inputs A, B, C, and D in order to get defined ground references?
Best regards!
Best regards!
A close look at the schematics reveals that my question has become obsolete. In differential mode each input's impedance is 10 kohms, defined by resistors R7, R42, R20 and R27, which are grounded virtually by the inverting buffers. So no external resistors necessary, even with a floating signal source.
But I've discovered another issue: The differential input sensitivity is much too high at 4 Veff for full power. As I provide XLR terminals, 1.55 Veff are more appropriate. So I have to increase the buffers' gain by replacing the feedback resistors by new ones with 26 kOhms. What would be the best and safest way to remove the original SMD components without destroying the PCB?
Best regards!
But I've discovered another issue: The differential input sensitivity is much too high at 4 Veff for full power. As I provide XLR terminals, 1.55 Veff are more appropriate. So I have to increase the buffers' gain by replacing the feedback resistors by new ones with 26 kOhms. What would be the best and safest way to remove the original SMD components without destroying the PCB?
Best regards!
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Oops! Those resistors around the NE5532 buffers are high precision 0.1% ones! I'll have to bring my idea to a halt until I can source resistors of the E192 value of 25.80 kohms, a tolerance of just 0.1 % and a suitable SMD package (which one?).
Best regards!
Best regards!
27k parallel 560k gives you 25758.09 which is -0.17% off.
Btw. 25k8 or 26k isn't that important as long as they're matched.
Btw. 25k8 or 26k isn't that important as long as they're matched.
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Sure. But at least the 27k has to be within 0.1 %. Which SMD package is the suitable one?
Best regards!
Best regards!
Why does it? The 0.1% is only necessary to minimize any imbalance in the differential structure as it would get amplified as well resulting in increased noise.
SMD package is what fits for you 0402, 0603 etc. just keep voltage rating in mind.
SMD package is what fits for you 0402, 0603 etc. just keep voltage rating in mind.