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3E Audio 260-2-29A : TPA3255 / HA3588 CoilCraft / PFFB Fully differential.

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Yeah I think is that, I just short the + on the + and the - on the -, I think it's a "bridge". For have one out
I recommend you to wait that 3e audio answers. Normally in these amps the short is done before the output filter.
 
Yeah I think is that, I just short the + on the + and the - on the -, I think it's a "bridge". For have one out

You cant bridge the Stereo module. This has already been discussed )
 
Hi, I have a other question, one the amp of 3E audio, can I short circuit theses two out for create a one out amp, and with I will power my ways system in parralele, so I will have a system with 2.66 Ohm .

Is it possible ?
it may work but not guarantee,that is why a dedicated PBTL config is used.
 
it may work but not guarantee,that is why a dedicated PBTL config is used.
Thanks for your response.
Do you have a other similar product with PBTL at 3E audio to advise me for power a 3 ways system in parallele like a ~ 3 Ohm system
 
1 x 260-2-29A - BTL(2channel) for stereo
1 x 480-1-29A - PBTL(1channel) for sub
 
3E Module :

LLC/PFC / Soft Start PSU :

If you want to check my APX555 Meausurements for this combo :

Could you please help me with a couple of questions:
1. For the SMPS I got from the audiophonics, for the power one button, does it need to be latching or momentary? Here is the PSU manual: https://www.mornsun-power.com/html/pdf/LOF550-20B48-C.html
2. From what I understood I just need to get two power wires from the SMPS to the amp? Id doesn't require any connection on the J5 connector (PS_CTRL, CLP, REST, FAT, FAULT, GND, CLP_OT, GND, IOP, IOM)?
Thank you!

Getting all the parts here, pretty excited to put it together
 
@rbg not sure i fully understand you Q1 but here are my suggestion:
  1. normally just add ON/OFF control AC input to the SMPS,i do think this is the simplest, like we did on the ASR measurement sample
  2. correct. no need connection on J5 unless you want more feature control the amp.
 
@rbg not sure i fully understand you Q1 but here are my suggestion:
  1. normally just add ON/OFF control AC input to the SMPS,i do think this is the simplest, like we did on the ASR measurement sample
  2. correct. no need connection on J5 unless you want more feature control the amp.
Thank you.
so here a couple of things I combined from the psi manual. Form what I understand these PS_ON high and PS_ON low can control on/off on the psu. One thing is I always get confused with these digital high/low stuff: does this mean that I need to 5V from the standby to that PS_ON high to turn it ON? Similar, disconnect it and connect PS)ON low to the GND to switch it off? Or you don't need a connection it is a momentary connection 5V->PS_ON high will turn it on and GND->PS_ON low will shut it down?
 

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Thank you.
so here a couple of things I combined from the psi manual. Form what I understand these PS_ON high and PS_ON low can control on/off on the psu. One thing is I always get confused with these digital high/low stuff: does this mean that I need to 5V from the standby to that PS_ON high to turn it ON? Similar, disconnect it and connect PS)ON low to the GND to switch it off? Or you don't need a connection it is a momentary connection 5V->PS_ON high will turn it on and GND->PS_ON low will shut it down?

Make it easy. Get any ON OFF IEC switch like I did with all my "Bamboo" project.
For the led, get a 220V led )

 
@rbg not sure i fully understand you Q1 but here are my suggestion:
  1. normally just add ON/OFF control AC input to the SMPS,i do think this is the simplest, like we did on the ASR measurement sample
  2. correct. no need connection on J5 unless you want more feature control the amp.
What is the gain of the amp? Am I correct that the amp needs 3V to go to full power? I plan on using it with RME interface that can deliver a lot of Volts. I should probably make some sort of gain reduction L-pad or something. Do you have any suggestion what would be the bast way to lower the gain, so I would need something like 9V to drive it to full power? :)
 
What is the gain of the amp? Am I correct that the amp needs 3V to go to full power? I plan on using it with RME interface that can deliver a lot of Volts. I should probably make some sort of gain reduction L-pad or something. Do you have any suggestion what would be the bast way to lower the gain, so I would need something like 9V to drive it to full power? :)
If you mean the RME ADI devices, then you don't need to build anything. You can adjust the output voltage over a wide range.
Bildschirmfoto 2024-06-05 um 10.49.29.png
 
It is UCX II. Also it’s for musical instrument and recording setup, so pops happen quite often there. UCX for example doesn’t have such good power on/of silencer as ADI-2 does
 
UAN,

I replaced the two Rin (200ohm)and the two Rf (1240 ohm) around the OPA1612s with new Rin =300ohm and new Rf = 1000ohm (used 1% 50ppm MELF 0204 resistors). Also the 4.7nF capacitor that's in parallel with the Rf need to be changed to 5.6nF, c0g(np0) MLCC capacitor to maintain the original filter bandwidth.
Hello S=klogW:,
does it work the same for SE input? Want to do it for a tweeter horn where I only need 1W.

Ralf
 
I am ready to fire it up. One quick question. LOF550-20Bxx-C Series has Vo+ and Vo-, do I connect Vo+ to PVDD and Vo- to the GND on the amp board? I assume that that PSU is single rail, so I am not sure why they marked it as + and -.
 
I am ready to fire it up. One quick question. LOF550-20Bxx-C Series has Vo+ and Vo-, do I connect Vo+ to PVDD and Vo- to the GND on the amp board? I assume that that PSU is single rail, so I am not sure why they marked it as + and -.

PVVD = +
GND = -
You got it ))
 
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Hello, still feel like a noob, but had a hard time figuring out a few things with my limited spare time so far.
I plan to push some 8ohm Jensen model 4 speakers with this board. I’ve seen there might be some trade offs depending on the PSU voltage though.
What would you choose for a PSU for this board that can deliver a lot of power but still retain low noise and distortion? (And the specific voltage, of course)

And I have read through a lot of this thread, but I’m still not entirely clear and I now have the board and just wanting to get it built finally. Seems like when I try to learn more about the theory, the references I can find either tell me the very basics that I already know, or they get very deep into the nuances of amplifier design at the level of an engineer designing a circuit around the opamp, etc… if anyone has any resource that’s like an intro to PSUs for class D amps that might be helpful, although not necessary. I mostly would just like to know a good model and the specific options to choose to get something loud and clean.

Thanks
I appreciate everyone putting up with my dumb questions. lol

EDIT: just to get it all out there… it also wouldn’t need a power switch at all since it will be in a rack, but that being said, soft start seems like a good idea in that case (from earlier conversation), and I would also be wanting a volume pot or some way to control attenuation, if that matters. The amp will be taking a line level balanced signal from my recording setup (preferably XLR or TRS 1/4”).
 
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Guys, I need your kine help: I'm trying to assemble my first ampli using the 3e AUDIO 260-2-29A modified to accept SE input signal. I'm an absolute beginner in this matter and I tried to get as much infos as I could. I tested the board with a cheap LDAC using my phone as a source and it sounded great. Then, since I took the chance to grab a 100k logarithmic pot by EIZZ at a very good price, I connected it between the LDAC and the ampli input. Well with great surprise and disappointment was terribly bad with the sound level constantly low all along the swipe and getting to max at the last two steps of the pot! The pot pins are marked as "IN-OUT-GND". I connected the LDAC output to "IN" and the ampli input to "OUT".
I replaced the EIZZ with a cheap linear pot getting a decently gradual regulation of the volume.
Can't believe I'll have to get rid of the EIZZ for a cheap linear pot!
What am I doing wrong?
 
Guys, I need your kine help: I'm trying to assemble my first ampli using the 3e AUDIO 260-2-29A modified to accept SE input signal. I'm an absolute beginner in this matter and I tried to get as much infos as I could. I tested the board with a cheap LDAC using my phone as a source and it sounded great. Then, since I took the chance to grab a 100k logarithmic pot by EIZZ at a very good price, I connected it between the LDAC and the ampli input. Well with great surprise and disappointment was terribly bad with the sound level constantly low all along the swipe and getting to max at the last two steps of the pot! The pot pins are marked as "IN-OUT-GND". I connected the LDAC output to "IN" and the ampli input to "OUT".
I replaced the EIZZ with a cheap linear pot getting a decently gradual regulation of the volume.
Can't believe I'll have to get rid of the EIZZ for a cheap linear pot!
What am I doing wrong?
can you show a diagram how is your connection?
 
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