Jaffrie,
The smd resistor can be low noise sussumu between 30 to 100 ohms, or just 50 ohms ! John advise also greater values for I2S attenuation : look at him thread (but beginn at the middle as it's long and had multi versions of the initial design !)
SMD inductors/ferrite beads can be added before the last bigger caps of the three powers voltage and a bigger cap at a edge of the board between. My understanding is when you have multiboards with a phoenix connector for PS is you need the first local decoupling caps have to be near the connector at the edge of the pcb ! General rule of design...maybe i'm wrong. Do you think stand alone 47 uH or 100 uH Murata should not be better ? or ferrite beads (600 ohms ?) . I have no knowledge here... or elsewhere actually !
So for each phoenix connector for PS board (three voltages), then three caps: one for each connector, let say 100 to 470 uF then each voltage. Then serie ferrite beads or smd inductor, then local polymer at 2 or 4 cm to the pins, then on the pins : decoupling with 605 case X7R cap for the best inductance, stay DIY soldering friendly.
What do you think of that ? Others, any experience, here I try to understand it with looking at others pcbs...
The smd resistor can be low noise sussumu between 30 to 100 ohms, or just 50 ohms ! John advise also greater values for I2S attenuation : look at him thread (but beginn at the middle as it's long and had multi versions of the initial design !)
SMD inductors/ferrite beads can be added before the last bigger caps of the three powers voltage and a bigger cap at a edge of the board between. My understanding is when you have multiboards with a phoenix connector for PS is you need the first local decoupling caps have to be near the connector at the edge of the pcb ! General rule of design...maybe i'm wrong. Do you think stand alone 47 uH or 100 uH Murata should not be better ? or ferrite beads (600 ohms ?) . I have no knowledge here... or elsewhere actually !
So for each phoenix connector for PS board (three voltages), then three caps: one for each connector, let say 100 to 470 uF then each voltage. Then serie ferrite beads or smd inductor, then local polymer at 2 or 4 cm to the pins, then on the pins : decoupling with 605 case X7R cap for the best inductance, stay DIY soldering friendly.
What do you think of that ? Others, any experience, here I try to understand it with looking at others pcbs...
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Also a question, under the I2S traces on the other side of the board should there be no earth plane to reduce capacitance as well?
Regards the inductor, need to do calcs on the resonant freq as I tune RF welders using tank circuits in the 27 and 40MHz ranges.
Is it possible to add through hole connections for the MSB caps and put the ground side under the chip or at least the caps under the board? Couple blokes here want to test several sets of caps against the recommended versions to check sound differences.
Thanks for efforts gents, this looks most promising!
Chuz,
Drew.
Regards the inductor, need to do calcs on the resonant freq as I tune RF welders using tank circuits in the 27 and 40MHz ranges.
Is it possible to add through hole connections for the MSB caps and put the ground side under the chip or at least the caps under the board? Couple blokes here want to test several sets of caps against the recommended versions to check sound differences.
Thanks for efforts gents, this looks most promising!
Chuz,
Drew.
Hi guys,
Slightly off topic. Years ago I experimented with choke input supply to a CS 4328 with no regulators & it was the most analog sound that i have ever heard from a dac. Problem was voltage fluctuation which eventually killed the dac. Tried regulators in front of chokes to control voltage but that didn't work. If I can get it to work this time round, won't hesitate to use it again. There's just no regulator haze in the sound at all. It's akin to
using dc for tube filament, the minute you use fix voltage regulator a certain electronic haze can be heard.
Slightly off topic. Years ago I experimented with choke input supply to a CS 4328 with no regulators & it was the most analog sound that i have ever heard from a dac. Problem was voltage fluctuation which eventually killed the dac. Tried regulators in front of chokes to control voltage but that didn't work. If I can get it to work this time round, won't hesitate to use it again. There's just no regulator haze in the sound at all. It's akin to
using dc for tube filament, the minute you use fix voltage regulator a certain electronic haze can be heard.
Hey mate, I've no idea.. outside of the basic inductance = impedance to AC, which is what were both saying.. ringing.. well, resonance between inductance and capacitance.. both impedances
.. needs a bigger brain than mine.. any they're probably already considered it.. just to nudge them if overlooked. As to how and why, over my head. Cheers,
Shane
Different regulators work in different ways. I like regulators operating without feedback for use tda1541A. Others find CCS fed TL431 just fine.
Anyway, with the board that ryan j. has, just the last filter is on the board, so you can use what you like anyway and still make good use of the PCB.
Hi,
I have less understanding than all of you, here my two cents :
Set3up said than a aditional vias on a strip after the uf.l connector will ruin all the effort (for the one using th uf.l connector, not the vias for flat wire). So if a output signal vias is needed in a RF strip where a uf.l connector is needed : the vias has to be on the middle of the pad where the signal lead (hot point) of the uf.l conector has to be soldered ! Or the matching impedance with the daughter board should be ruined ! Of course if the PCB cames already from a supplier with the uf.l soldered : just forgett the vias in the design. But here for the moment it's DIY friendly with the tools we have... here the soft Ryan uses.
Elswhere it's less important. For power caps it seems less important here but look at in the amr product at Sixmoons link where the bulk caps are: close to the chip body. The idea is if you use smd caps with strips and vias for bulk caps in each sides of the smd pads for soldering: it ruins the inductance : so never use vias on the small decoupling caps near the chips (the 0.1 nf caps) but in the middle of the soldering pads like said Marce fellow.
T. Loesch said here than ceramic has to be avoid for MSB : so if vias of the MSB decouplings pads : pitch has to be 2 mm e.g. for wima MKS2 (max 1 uf) than Mr T use himself at home (testimonies above) and here soldered below the pcb head in bottom position. Set3up testimonied above than smd film caps can be killed too easily with diy use (Soldering iron EMC + the hands of the diyer !!!). So trade off has to be found : acylic like ECDESIGNS, or polymer tantal, tanta, or less fragile smt film caps ! Don't know myself, I liked elswhere with tda1540 the wimas.
About the gnd plain for MSB, many testimonies above in this thread from T. Loesch and Set3up. A testimonie as well who said than ECdesigns give up to come back with a plain continous ground plane ! T advised to go with a piece of copper foil around the body of the chip for inductance & EMC but don't understand which gnd pin is used : ask Set3up here...
For power supply if the core board is a little one for everybody which seems to be the way we follow now i really think like i say above than a design with caps near the chip and near the edges of the pcb (where the phoenix connector for PS are) is the way to follow : a ferrite bead before the two bulk caps with two smd pads could be a good idea (people will put what they want here). here a third pad can be added on the gnd layer for a three lead ldo reg instead (like the TI low noise I linked above in the thread) but think than a ferrite bead or inductor should be enough... For me the bulk caps pads have to be two pitch for choosing the "flavor caps" 2.5 and 5 mm pitch on the gnd side : so three vias : one for the power strip and two for the gnd to choose the width !
I will say here before Ryan loose time we need testimonies about the ground loops and the gnd pins and powers pins of the chips ? Set3up ? Anybody else experienced who read this thread ? Question to ECdesigns in his thread ? (But I'm the first to think than too much people ask too much to John with 2 cents questions...).
Eldam
I have less understanding than all of you, here my two cents :
Set3up said than a aditional vias on a strip after the uf.l connector will ruin all the effort (for the one using th uf.l connector, not the vias for flat wire). So if a output signal vias is needed in a RF strip where a uf.l connector is needed : the vias has to be on the middle of the pad where the signal lead (hot point) of the uf.l conector has to be soldered ! Or the matching impedance with the daughter board should be ruined ! Of course if the PCB cames already from a supplier with the uf.l soldered : just forgett the vias in the design. But here for the moment it's DIY friendly with the tools we have... here the soft Ryan uses.
Elswhere it's less important. For power caps it seems less important here but look at in the amr product at Sixmoons link where the bulk caps are: close to the chip body. The idea is if you use smd caps with strips and vias for bulk caps in each sides of the smd pads for soldering: it ruins the inductance : so never use vias on the small decoupling caps near the chips (the 0.1 nf caps) but in the middle of the soldering pads like said Marce fellow.
T. Loesch said here than ceramic has to be avoid for MSB : so if vias of the MSB decouplings pads : pitch has to be 2 mm e.g. for wima MKS2 (max 1 uf) than Mr T use himself at home (testimonies above) and here soldered below the pcb head in bottom position. Set3up testimonied above than smd film caps can be killed too easily with diy use (Soldering iron EMC + the hands of the diyer !!!). So trade off has to be found : acylic like ECDESIGNS, or polymer tantal, tanta, or less fragile smt film caps ! Don't know myself, I liked elswhere with tda1540 the wimas.
About the gnd plain for MSB, many testimonies above in this thread from T. Loesch and Set3up. A testimonie as well who said than ECdesigns give up to come back with a plain continous ground plane ! T advised to go with a piece of copper foil around the body of the chip for inductance & EMC but don't understand which gnd pin is used : ask Set3up here...
For power supply if the core board is a little one for everybody which seems to be the way we follow now i really think like i say above than a design with caps near the chip and near the edges of the pcb (where the phoenix connector for PS are) is the way to follow : a ferrite bead before the two bulk caps with two smd pads could be a good idea (people will put what they want here). here a third pad can be added on the gnd layer for a three lead ldo reg instead (like the TI low noise I linked above in the thread) but think than a ferrite bead or inductor should be enough... For me the bulk caps pads have to be two pitch for choosing the "flavor caps" 2.5 and 5 mm pitch on the gnd side : so three vias : one for the power strip and two for the gnd to choose the width !
I will say here before Ryan loose time we need testimonies about the ground loops and the gnd pins and powers pins of the chips ? Set3up ? Anybody else experienced who read this thread ? Question to ECdesigns in his thread ? (But I'm the first to think than too much people ask too much to John with 2 cents questions...).
Eldam
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Yeap, to come back to post#1 (any godd tda1541 kit ?)
We are not many here my very young padawan. I can hear the Empire strike back against our little utopic republic !
Vano has vanished
Audiolapdance swaped the last dance
The good jedis have gone or didn't accept the fight...sorry: the challenge
Set3up became a Sith or get holliday with Leia on Naboo !
I'm getting old and become tired to try to drive alone my T.fighter !
I wish we were more and come to a cute 4 layers as it's not expensive to print nowadays and finally people showed the y have enough experience and knowledge together when exchanging ideas. I'm sure it is possible if more good willed and knowledged people were here ! I realyy think there is a place between the crap copycat kit with bad layout (why put good component like i see elswhere if the layout is bad ?) and the SOTA branded gears ! BUT....
In fact just one guy did it : Mr Pedja R. John ECdesigns tried but gave up (remember him little module... it was expensive cause North Europe price).
Think also that the only way is to go for a crystal near the chip with a stacked ps board (or not, here the idea is to go for options... but often options= bad layout) to try to slave the DEM clock at 175 with dividers or to go for a good asyncrnous usb (I have some difficulty to find something compatible with I2S/16 bits) or the expensive Fifo....
And of course I am on SB Duett so no USB for myself... maybe a clone of squeezebox server with a DSP to USB/I2S device could save my needs (RasberryPI ?) but the price of the complete project is raising. The professional worldof reccording & studios is more accurate with devices with Sony interace or IP rj 45 plugs to ours music datas stored on domestical networks. Audiophile world his just capable to deal with USB with a computer near the device...pfffffff. Logitech gave up to increase their smart SqueezeBox. The verity is than the audiophiles brands are late (but the music quality of course) with the spidf (which is born dead) and the USBs
So now I'm to prepar the breakfast and beginn when the home will be empty after a training to laser sword : I'm getting to cut the hands bags of the old ladies in the street... Here in France they have no more money in its since the subprimes crisis but as they are often Vuitton, Hermes... I can make an exchange with an off the shelves chineese DAC !
But it can sucees here if we are able to do simple like the last draw of RyanJ...share it for further versions and try to print it or share it on a web plateform (not the Dark Star, noooooooooooo !)
I'm asking myself if I'm not going to verroboard with the T. advises (but good luck for the matvhing impedance for I2S and uf.l connectors on a verroboard, even if some exists with continous plane, vias to gnd and very smal pads for smt devices....)
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wife is an ewok girl, we 've got a good vacum cleaner for the carpets !
ahhh the blond australian girls... and me who believed than Leia with her white clothes escaped from a dental surgery for naughty Siths...
Before have to go to see the Family at the moutain in the french Alpes
Bigfoot filmé par un alpiniste canadien ? : golem13
Do you think Vader broke him toy ? The AMR Black Stars with gnomes stage and call to Palpatine ?
The Emperor's Phone Call | Robot Chicken | Adult Swim - YouTube
ahhh the blond australian girls... and me who believed than Leia with her white clothes escaped from a dental surgery for naughty Siths...
Before have to go to see the Family at the moutain in the french Alpes
Bigfoot filmé par un alpiniste canadien ? : golem13
Do you think Vader broke him toy ? The AMR Black Stars with gnomes stage and call to Palpatine ?
The Emperor's Phone Call | Robot Chicken | Adult Swim - YouTube
Ewok, you've got good taste and they're a good height.. saves on knee pads.
Bigfoot. I saw a doco about strangest ways to die, this guy moved to a place near the woods for some tranquility and soon found himself annoyed the local jogging community who were constantly disrupting his peace. So he dressed up as Bigfoot and started scaring them. It sort of worked, until word got out and the local Ranger (who happened to be a Bigfoot enthusiast) came up to hunt him. Shot him with a dart loaded with horse tranquilliser and killed him.
Not sure if Wookies have that problem, but I can see from the link how confusion could creep in.
Bigfoot. I saw a doco about strangest ways to die, this guy moved to a place near the woods for some tranquility and soon found himself annoyed the local jogging community who were constantly disrupting his peace. So he dressed up as Bigfoot and started scaring them. It sort of worked, until word got out and the local Ranger (who happened to be a Bigfoot enthusiast) came up to hunt him. Shot him with a dart loaded with horse tranquilliser and killed him.
Not sure if Wookies have that problem, but I can see from the link how confusion could creep in.
Course the link sticking would be useful....http://www.diyaudio.com/forums/twisted-pear/250583-building-open-embedded-audio-applicance.html
Looking good. We'll wait a bit for any more suggestions and then pack up the Gerbers and get some PCBs made.
Good work!
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