The output filter Approximate match the design. The inductors are 2 x 22 uH, paralelled, = 11 uH as opposed to the original 10 uH recommendation. Unfortunately, better quality, 10 uH Coilcraft or Würth inductor doesn't fit.
The 22mh, 1uf combination seems to correspond with Ti's recommendations for building an amplifier around the chip from what I've read off their data sheets but I can't confirm it's an optimal arrangement. You'll need the smart fellows to weigh in on this one.
Have you every compared the sound of this board against other versions? If the other versions have better treble detail, the inductors can be bad quality and/or 1uf ceramic cap is the reason. There is little space on the board, it is hard to replace them with film cap.
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This is just personal experience so take it with a grain of salt. I bought an aiyima a07 (I believe a later revision than the extensively reviewed model) and found it quite nice at normal listening levels though for me, bass was a little thin. The shui yuan tpa3255 modified with 4700uf filters for me has a more fuller sound and very similar sounding to some of my vintage class ab amps (once the volume is raised above a certain threshold. The new tpa3255 we're talking about in standard form I found quite detailed with a slightly expanded sound stage - nice at low volume, but loses its coherency as the volume increases. The capacitor swap I've already mentioned expanded the sound stage considerably. Mids are brought forward and aren't lacking in any way, remains coherent with increased volume. My only complaint would be that it may be a little dry sounding in places but on balance I'm leaning towards it over the others - especially for the expanded staging. I'm running these on Mordaunt ms. 10 speakers, so again your milage may vary.
One last thing. I upgraded on of my two boards (the model we're talking about) following the formula set by one of the chaps earlier in the discussion. I couldn't get my hands on 2200uf filter caps so when with 3300uf 25v (there is a revised version of this board that uses the 3300uf's and red input caps - so I reasoned it an okay substitute). I left the 3 x 50v capacitor bank untouched for first testing, keeping it the same as the revised board I was effectively modelling it off. It sounded awful. Mids may have well have been delivered through a butt hole in a wind tunnel. Sounded spacial but with large portions of the sound stripped away - if that makes sense? I replaced the entire 50v bank with new 3x1000uf caps and this immediately improved the situation (but not perfectly). That's when I replace the 470uf in my reference board with one of the factory 1000uf caps (from the other) to gage how increasing/decreasing capacity changes the sound of this amp - and now the answer seems pretty clear (to me at least). As I mentioned earlier - board sink screen calls for 3x1000uv 50v caps, factory installs equ. of 2470uf but actually measures around 500uf less than that.
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Gday buddy. From what I glanced from the TI datasheet, the recommendation for a 450khz implementation is for a 22mh coil/ 1uf cap combination. But if I understanding you right the designers have setup the coils design in such a way that a 600khz setup would have been a better choice?
it seems that the manufacturers simply took the scheme from the BTL datasheet as a basis and, as far as they could, implemented it on existing components at minimal cost. at the same time, judging by the resistor of 30 kΩ, the version is implemented in the "normal" mode with a frequency of 450 kHz, which is considered in all datasheet tables. recommendations on the value of the inductance is difficult for me to evaluate. what kind of AM2 mode, for which the carrier frequency is 600 kHz, is also not clear. again, how this mode differs in sound is not clear. By the way, on the page with an example of wiring, a 10 kΩ resistor is indicated. Does anyone have the opportunity to compare this amplifier board with another, on high-quality components and with the correct wiring? what is the carrier frequency? previously paid attention to 3eaudio products, they seemed to me of better quality, but now they are not available
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The stereo BTL setup's recommended coil size is 10 uH, if I read correctly the datasheet. Unfortunately, I don't understand electronics at this level, so I can't tell you which oscillator setting is better.
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Big D Wiz ran a dyno on the Aiyima A07 with the provided 32v 5a power supply and bought a 48v 5.2a power supply. 170 watt @ 4 ohm 1% THD and 200 watt @ 4 at clipping using the 48v power supply. Not too bad. I wonder if you can get the rated 255 watt @ 4 ohm 1% THD using a 600 watt power supply?
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Yes you can. I use a 54 volt power supply that sags a bit under load and 300+ @ 4 ohms is not a problem. 8 ohms is around 170 if I remember correctly. It's been a few years.
any suggestions for a volume control pot with PCB to mount it? Also where can I source one thats with a pcb and no op amps etc.Ebay is all long ship time.
I'm using a JV8 relay input selector/volume control, but I modified to 10 kOhm, with appropriate Beyschlag metal film resistors.
I have just tried another seldom mentioned op-amp with the SHUIYUAN and I am
delighted with its soundstage. OPA2134 from T.I.
see : https://www.ti.com/lit/gpn/opa2134 and see : https://www.ti.com/lit/pdf/sboa345
If you want to try it it is active and you can get ir from Mouser , Farnell , Digikey etc.
It is DIP version so no problem to plug it in
delighted with its soundstage. OPA2134 from T.I.
see : https://www.ti.com/lit/gpn/opa2134 and see : https://www.ti.com/lit/pdf/sboa345
If you want to try it it is active and you can get ir from Mouser , Farnell , Digikey etc.
It is DIP version so no problem to plug it in
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Whats the best sounding 3255 or 325x amplifier you can buy today?
With or without enclosure.
I know this one is the «original»:
https://no.mouser.com/new/texas-instruments/ti-tpa3255evm-evaluation-module/
Topping get good reviews:
https://www.tpdz.net/productinfo/737898.html
Other suggestions?
With or without enclosure.
I know this one is the «original»:
https://no.mouser.com/new/texas-instruments/ti-tpa3255evm-evaluation-module/
Topping get good reviews:
https://www.tpdz.net/productinfo/737898.html
Other suggestions?
Not the best opinion of PA5 owners, more than 46% of dissatisfied users.
https://www.audiosciencereview.com/...oll-for-topping-pa5-owners-only-please.33293/
JL looks nice.
I mailed them and asked if 32V is enough and the answer was yes.
I have a off grid cabin with solar power and 260Ah battery.
I will use a Victron DC/DC stepup converter from 12V DC to 32V DC (Max 20A)
I read on the JL webshop that you can buy it with or without op amps.
Will this be an upgrade or is it just unsignificant differences?
https://sparkoslabs.com/discrete-op-amps/
I mailed them and asked if 32V is enough and the answer was yes.
I have a off grid cabin with solar power and 260Ah battery.
I will use a Victron DC/DC stepup converter from 12V DC to 32V DC (Max 20A)
I read on the JL webshop that you can buy it with or without op amps.
Will this be an upgrade or is it just unsignificant differences?
https://sparkoslabs.com/discrete-op-amps/