Wiliks, appreciate the effort you have taken to confirm on your side ~ that sudden unplugging of 32V power supply does not produce any pop.
I will check again on my side ~ not sure maybe if swap in new LME49720 opamp wld address my pop sound from the earlier provided NE5532.
Hi Forestsgump
Sorry to read that you are still have this pop on/off problem. as i learned at the TPA3255 YJ board ....... tps3802_supply voltage supervisors "ARK" chip :
there is a chip inside of the FX502Spro to manage this on off behaivour...check maybe the datsheet which values you should have.
chris
I was considering picking up a Volt+D, but really wanted something up to that quality but with TPA3250, so I emailed Allo (mfg of the Volt+ TPA3118 amps) the other day, was told they are working on a TPA3255 unit and it should be out in 4-6 month.
Finally we can have a quality layout and parts selection fully finished amp based on TPA32**
. The FX502Spro is nice but it can really be improved on and unfortunately I missed out on the only run of Stereo Wiener TPA3250's I'm hoping for socketed OPAMP but they usually don't do that, in any case I trust their parts selection a lot more than FX audio.
It really boggles my mind why there still isn't a quality finished amp available based on TPA3250 series..., sure start up capital may be an issue but there is things like kickstarter to mitigate that
Finally we can have a quality layout and parts selection fully finished amp based on TPA32**
. The FX502Spro is nice but it can really be improved on and unfortunately I missed out on the only run of Stereo Wiener TPA3250's I'm hoping for socketed OPAMP but they usually don't do that, in any case I trust their parts selection a lot more than FX audio.It really boggles my mind why there still isn't a quality finished amp available based on TPA3250 series..., sure start up capital may be an issue but there is things like kickstarter to mitigate that
I was considering picking up a Volt+D, but really wanted something up to that quality but with TPA3250, so I emailed Allo (mfg of the Volt+ TPA3118 amps) the other day, was told they are working on a TPA3255 unit and it should be out in 4-6 month.
Finally we can have a quality layout and parts selection fully finished amp based on TPA32**
It really boggles my mind why there still isn't a quality finished amp available based on TPA3250 series..., sure start up capital may be an issue but there is things like kickstarter to mitigate that
hi
you are right....it was a 3e-tpa3250 board...but now in the group buy its "just" tpa3251/3255.....
which failures did you uncover at the f502spro board ?
chris
I couldn't found a fair price case and ended up buying a 10 usd small car safe for the Mean Well P. S. [emoji2944]
It's bulky, but works well. I'm still waiting for the FX-Audio though
nice !!!
...as i can read you do the safety earth connection write the first time because you read my post....finechris
I don't have that PSU (yet), but I see that the B1304 case (commonly available on eBay/Aliexpress) should be just big enough to fit, but ONLY if you hard-wire the power cord. If you search hard, you can find them for under $15 shipped, So a bit more expensive, and won't fit an IEC socket, but nicely finished and compact...
LRS-150-24 dimensions: 159*97*30mm (per datasheet)
B1304 internal dimensions: 160*120*35mm (measured)
I have the enclosure that I got as a spare for another project. Now I just need to get the LRS-150 B1304 internal dimensions: 160*120*35mm (measured)
UPDATE: Actually, I just measured a clip-in IEC socket, and if you're VERY carefull, and orient it vertically, you might be able to fit in the case it alongside the PSU. But then your 24V socket would have to be mounted directly above the supply's screw terminals. Tight. Very tight.
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The chassis is connected to earth through the power supply body, I checked continuity with the DMM and it is working fine, but I didn't put a redundant earth safety wire [emoji87]
It looks like the volume of that case on Aliexpress is in the threshold of cheap shipping, because I couldn't find something bigger for a fair price
It looks like the volume of that case on Aliexpress is in the threshold of cheap shipping, because I couldn't find something bigger for a fair price
No specific failures, but i prefer something with higher quality components and more careful layout work. Some specific things that I am looking forward to:
-proper stepped attenuator volume control vs the cheap crappy detented pot on the fx502-- properly matched L/R
-real (not fake) components, and decent quality ones
-easily controllable switching freq and gain settings via switch/jumper
I don't care if it has a cheap plexiglass case, when I first got my TPA3118 weiner board I really gained an appreciation for what proper PCB should look like vs the chinese stuff. Then I saw doctormods nice boards but those aren't purchasable. To be clear I have no interest in soldering or any assembly work, my hand is not steady and my EE knowledge is basic at best--I want a fully finished amp. The few times I have soldered have either just been a mess or a complete disaster. But a well engineered board is aesthetically pleasing for me in addition to sounding good.
Oh wow I didnt notice 3e was doing GB now. In any case I think allo provides higher quality overall and I am more interested in a finished product than a board. I had considered a 3e before, but tbh they don't seem that much better than the FX502 for me, in fact even worse because it is not a finished amp, and it does not even have socketed OPAMP, and components and layout do not look as nice as the stuff allo does. I don't mind paying a little bit more for quality. I also want to support electrical engineering work being done outside of China when I can.
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Has anybody been advantageous enough to bypass those crappy OpAmps and feed the chip directly with a balanced signal?
I have done that with all my gear that came with OpAmps and the sound quality always improved.
For domestic listening levels the TDA chips can easily do without any pre amplification.
At the moment I am transformer coupling my DSC1 balanced into the TDP3116 and the result is
absolutely fantastic.
I have done that with all my gear that came with OpAmps and the sound quality always improved.
For domestic listening levels the TDA chips can easily do without any pre amplification.
At the moment I am transformer coupling my DSC1 balanced into the TDP3116 and the result is
absolutely fantastic.
Hi
i am not an expert so please wait until one confirm this:
in the implementation of fx502Spro it will not be easy because the board is not build for the differential/balanced input.
as you can read a the datasheet of the TPA3250EVM board you see 4 different input jacks...i show you in the pic attached what i mean.--> so this is the way it should be (jumpers set to diff) to feed the TPAchip with 1 channel differential-balanced.
chris
i am not an expert so please wait until one confirm this:
in the implementation of fx502Spro it will not be easy because the board is not build for the differential/balanced input.
as you can read a the datasheet of the TPA3250EVM board you see 4 different input jacks...i show you in the pic attached what i mean.--> so this is the way it should be (jumpers set to diff) to feed the TPAchip with 1 channel differential-balanced.
chris
Attachments
is the idea of feeding the amp a balanced signal to avoid deficiencies in the DAC or in the amp?
My understanding was that balanced is used to avoid noise in situation with for example long cable runs-- is there some further benefit to it other than this? Even if you are avoiding OPAMP by running balanced, you introduce (expensive) transformers in their place (unless you have a DAC with balanced output).
My understanding was that balanced is used to avoid noise in situation with for example long cable runs-- is there some further benefit to it other than this? Even if you are avoiding OPAMP by running balanced, you introduce (expensive) transformers in their place (unless you have a DAC with balanced output).
I've received an email from Hifimediy announcing the upcoming UDP320, a fully digital ddx amp with spdif and usb input and 2x150 watts speakers output.
It works without dac conversion:New Fully digital DDX amplifier, the UDP320
They already launch the UDP80, a similar version with 2x80 watts @ 8 ohm (110 usd).
Does someone knows from experience how does those kind of PWD amps sound compared to a good dac and a good TDA/TPA amp?
It works without dac conversion:New Fully digital DDX amplifier, the UDP320
They already launch the UDP80, a similar version with 2x80 watts @ 8 ohm (110 usd).
Does someone knows from experience how does those kind of PWD amps sound compared to a good dac and a good TDA/TPA amp?
I got one of their DDX amps several years ago, was not happy with the sound quality at all, returned it. In addition to the bad sound quality there was some quality control issues-- one of the channels was really messed up and had bad buzzing. Compared w/ JDSlabs dac and TPA3118 amp the TPA3118 was much better. The technology seems smart in theory but if it was so good should have easily outperformed my TPA3118 (I had Weiner board, and SMSL SA60).<br />
I am waiting for Allo's upcoming TPA3255 amp, not heard their products before but just looking at their PCBs they look much better engineered and built and they use stepped attenuators as well. Some of the more knowledgeable members here have called them out on fake components before, but it seems they did respond and were interested in fixing the issue with their supply chain.
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Hi
i am not an expert so please wait until one confirm this:
in the implementation of fx502Spro it will not be easy because the board is not build for the differential/balanced input.
as you can read a the datasheet of the TPA3250EVM board you see 4 different input jacks...i show you in the pic attached what i mean.--> so this is the way it should be (jumpers set to diff) to feed the TPAchip with 1 channel differential-balanced.
chris
Datashit suggests connecting a balanced signal directly through capacitors. Capacitors are not needed unless there is a constant input voltage.
Attachments
Hi
i am not an expert so please wait until one confirm this:
in the implementation of fx502Spro it will not be easy because the board is not build for the differential/balanced input.
as you can read a the datasheet of the TPA3250EVM board you see 4 different input jacks...i show you in the pic attached what i mean.--> so this is the way it should be (jumpers set to diff) to feed the TPAchip with 1 channel differential-balanced.
chris
Datashit suggests connecting a balanced signal directly through capacitors. Capacitors are not needed unless there is a constant input voltage.