Arghhhhh the price of those chips would drop !
Thanks John for the inputs.
It's not clear to me in an I2S flux what is the cause of the changing state : switch of/on curent and voltage (One & zero coding) ? Does a higher sampling frequencies makes the things worst or the speed of the PCM switching gets the things better about this switching noise ?
What is an I2S transcient ? more datas in a same period ? a voltage/current spike ? Is it changed by the speed (sampling frequency). I believe I don't understand the difference between the PCM modulation transport and the transport of encapsuled packets... but below it's the same no ? All analogic : voltage & current on a copper substrate ? Whic makes it "digital" is the speed involved : RF ?
In the same spirit, the more bit depth, the more switching noise as more PCM informations ? Did you have the same measurement with a compressed PCM à la FLAC between a raw WAV one ?
Very interresting (as usual with you) all those research you make on the total layout and environment of these dac chips.
thnaks for that.
cheers
Thanks John for the inputs.
It's not clear to me in an I2S flux what is the cause of the changing state : switch of/on curent and voltage (One & zero coding) ? Does a higher sampling frequencies makes the things worst or the speed of the PCM switching gets the things better about this switching noise ?
What is an I2S transcient ? more datas in a same period ? a voltage/current spike ? Is it changed by the speed (sampling frequency). I believe I don't understand the difference between the PCM modulation transport and the transport of encapsuled packets... but below it's the same no ? All analogic : voltage & current on a copper substrate ? Whic makes it "digital" is the speed involved : RF ?
In the same spirit, the more bit depth, the more switching noise as more PCM informations ? Did you have the same measurement with a compressed PCM à la FLAC between a raw WAV one ?
Very interresting (as usual with you) all those research you make on the total layout and environment of these dac chips.
thnaks for that.
cheers
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I have a friend who has directed me to this thread. He has informed me that over the 9 year span, there have been several changes in the circuit. Could someone direct me to where I could start in the 500+ pages to get into the latest and greatest. I usually take a lot of notes and don't really want to be bogged down in earlier configurations which are no longer used.
James
James
Thought about that a few times. But my goal is 100% protection from oxidation.
Intel Embraces Submerging Servers in Oil | Data Center Knowledge
Intel Embraces Submerging Servers in Oil | Data Center Knowledge
Very interesting idea. We can eventually think about covering the whole thing with epoxy - from one side it will settle the hermetization issue, however rolling on resistors could be a problem
Hello,
I am about to finish my Red Baron v5.0 NOS DAC. I'd like to go with Grounded-Gate MOSFET Current Buffer I/V Stage MK7 version designed by Johh (ecdesigns).
The question about the buffer stage is if I can safely use higher value of I/V resistor than 500R? Let's say 1k to get 1.41Vrms or 1k5 to get 2.12Vrms? What about Reference GND? May I use 3.3V DC Digital source? Or use 5.0V as in RedBaron v4.0? Or maybe higher: 10VDC or 15VDC according to higher I/V resistor value?
Best regards,
mhgawel
I am about to finish my Red Baron v5.0 NOS DAC. I'd like to go with Grounded-Gate MOSFET Current Buffer I/V Stage MK7 version designed by Johh (ecdesigns).
The question about the buffer stage is if I can safely use higher value of I/V resistor than 500R? Let's say 1k to get 1.41Vrms or 1k5 to get 2.12Vrms? What about Reference GND? May I use 3.3V DC Digital source? Or use 5.0V as in RedBaron v4.0? Or maybe higher: 10VDC or 15VDC according to higher I/V resistor value?
Best regards,
mhgawel
Very interesting idea. We can eventually think about covering the whole thing with epoxy - from one side it will settle the hermetization issue, however rolling on resistors could be a problem
It is easy to make a mold and cast epoxy over components, this will help thermal distribution and resonance damping. Make sure the temperature of some components will not melt back the epoxy.
Remember me the great days of old guru hifi when everybody putted quartz (sometimes sand) on the speaker filters boxes to avoid magical surface noise on parts and pcbs and wires also ! Is it parts damping VS air cooling ? I mean the best for thermal noise issues for most parts which are not transistor : just air.... instead oven cooking like a Poule au Pot ! Only the boeuf bourguignon is better when heated twice !
Thanks for the link, dear.
Mineral oil is apparently safe.
Maybe a little class A amp will be fit for experimentation.
Hi Max,
Is Ferro fluid conductiv or inert ? If inert: may have also the cooling effect !
Ah magnetic effect of ferro charge could be maybe a default (loaded from the circuit) or an advantage : EMC shield ? parts isolated from their own EMC on each others ?
As well : a good thick aluminium case around the little dac board isolate it both of vibration and EMC despite no being easy and totaly proof due to the inputs and outputs !
Maybe also try the very thin sand they use today in public ash-trays ?! (but not against oxydation ! Did you think about gold bath electrolytic to golden all the metalized contacts of the populated dac board with its parts and dac chip: I had this idea 20 years ago but asking myselfs if shorts can be avoided during the bath with such a method ? Sure some other fanatics thinked to it already ! Not so expensive, many people from old Europe make its with Mummy's forks !)
15 years ago a french semi bandit semi guru maked speakers wires with semi conductiv liquid around the conductiv wire to avoid skin effect while allow damping against external vibrations ! IIRC he never found bankeers despite being thieves themselves : a good fools trap ! Luckilly he stays more a guru than a bandit, missing of money to launch it (but believe there are some reccording brevet about it !)
Hum ... I should stop drinking ! John researchs are more serious ! So sorry for the OT !
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Hi maxlorenz,
The filter had to be removed again as it reduced transparency.
The products on our website are basically outdated, we have been working on an advanced XMOS-based USB receiver, a new SD-transport, and a revolutionary discrete D/A converter. These will be used in our new projects.
The filter had to be removed again as it reduced transparency.
The products on our website are basically outdated, we have been working on an advanced XMOS-based USB receiver, a new SD-transport, and a revolutionary discrete D/A converter. These will be used in our new projects.
Hi guys,
I feel this year the DIY forces return back to me anew: two DACs and an integrated amp for my brother.
Dear Eldam, I suspect mineral oil will make the TDA (and other DACs, like the DAM-thing) superconductive at room temp and noise figure will be negligible.
Dear John, with this dual-mono DACs I have been re-doing the path of the last years, introducing the mods one by one, after at least 48hrs of burning-in, just to confirm we (you) were right. Yesterday I added attenuators to BCK and WS and the effect was evident. Next, attenuators to both DATA lines, then removing trans-impedance amp, next will come DC coupling
Please tell "this is IT" about the SD player to pull the trigger.
Can you anticipate the new DAC's architecture?
Best wishes to all,
M.
PS: attenuator circuit could be one of the greatest contributions from John to the DIY community.
I feel this year the DIY forces return back to me anew: two DACs and an integrated amp for my brother.
Dear Eldam, I suspect mineral oil will make the TDA (and other DACs, like the DAM-thing) superconductive at room temp
and noise figure will be negligible.Dear John, with this dual-mono DACs I have been re-doing the path of the last years, introducing the mods one by one, after at least 48hrs of burning-in, just to confirm we (you) were right. Yesterday I added attenuators to BCK and WS and the effect was evident. Next, attenuators to both DATA lines, then removing trans-impedance amp, next will come DC coupling
Please tell "this is IT" about the SD player
to pull the trigger.Can you anticipate the new DAC's architecture?
Best wishes to all,
M.
PS: attenuator circuit could be one of the greatest contributions from John to the DIY community.
The heat moves towards the cold (thermal dynamic law ?) !
If the cold environment is colder than the material which need to be cooled, what do we need to know ?
- What is the best heat conductor
- while being the one to stay colder the most easily to help the warm material to get cold faster (and longer)
FerroFluid is conductiv ? (ferro particles) and have some magnetic properties to evacuate the heat and allow damping as well due to the viscosity !
Mineral oïl allow damping as well but is harder to get cold when hot ?
Air stay cold more longer due to the volume (if it is coldier than the stuff to be cooling)
Ah, what about époxy, enough soft to allow damping ! And what about caps : bare or with its époxy suits... Mystheeeeeeeeeeeeer ! ???
I see there are many sd players pcbs but are there some DIY FIFO boards already programmed in the markett but the one of Ian ?
If the cold environment is colder than the material which need to be cooled, what do we need to know ?
- What is the best heat conductor
- while being the one to stay colder the most easily to help the warm material to get cold faster (and longer)
FerroFluid is conductiv ? (ferro particles)
and have some magnetic properties to evacuate the heat and allow damping as well due to the viscosity !Mineral oïl allow damping as well but is harder to get cold when hot ?
Air stay cold more longer due to the volume (if it is coldier than the stuff to be cooling)
Ah, what about époxy, enough soft to allow damping ! And what about caps : bare or with its époxy suits... Mystheeeeeeeeeeeeer ! ???
I see there are many sd players pcbs but are there some DIY FIFO boards already programmed in the markett but the one of Ian ?
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The epoxy for audio transformers has 3 functions:
1. protects the wires from moving and shocks, vibration from external sources , the epoxy around it prevent it from moving
2. Dampening of resonances, this type of epoxy solidify to a certain degree. It keeps some bending and damping property like wood or hard rubber for comparisons. Instead of a single capacitor vibrating alone in its pins, the capacitor or wires are dampened by the semi elastic properties of the solid epoxy resin.
3. It helps the transformer or any components diffuse the heat around its body. The epoxy paste is a GOOD heat conductor and prevent any AIR thermal ISOLATION between the metal body and the turns of wires inside the transfo. For IC's and resistors it acts as an heat sink. The area of thermal contact with colder sourouding air augments thus lowers components temperature (it also helps by thermaly coupling components).
It is used in military applications and output audio transformers (sometimes chokes and power transformers).
Epoxy is very expensive but easy to apply. Fairly non toxic after it cures at room temperature or controlled low temp ovens.
Other places needed to mention is special high durability circuit boards: elevators control boards are covered in epoxy, industrial process control boards are too, many processors are also covered in an epoxy bubble (black). I use the transparent epoxy to seal components like screws and base of capacitors. It cost around 10$ for a small tube, it could cost as much as 100$ to buy small quantity of audio grade epoxy to cast an output transformer.
1. protects the wires from moving and shocks, vibration from external sources , the epoxy around it prevent it from moving
2. Dampening of resonances, this type of epoxy solidify to a certain degree. It keeps some bending and damping property like wood or hard rubber for comparisons. Instead of a single capacitor vibrating alone in its pins, the capacitor or wires are dampened by the semi elastic properties of the solid epoxy resin.
3. It helps the transformer or any components diffuse the heat around its body. The epoxy paste is a GOOD heat conductor and prevent any AIR thermal ISOLATION between the metal body and the turns of wires inside the transfo. For IC's and resistors it acts as an heat sink. The area of thermal contact with colder sourouding air augments thus lowers components temperature (it also helps by thermaly coupling components).
It is used in military applications and output audio transformers (sometimes chokes and power transformers).
Epoxy is very expensive but easy to apply. Fairly non toxic after it cures at room temperature or controlled low temp ovens.
Other places needed to mention is special high durability circuit boards: elevators control boards are covered in epoxy, industrial process control boards are too, many processors are also covered in an epoxy bubble (black). I use the transparent epoxy to seal components like screws and base of capacitors. It cost around 10$ for a small tube, it could cost as much as 100$ to buy small quantity of audio grade epoxy to cast an output transformer.
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Is it possible to a diyer to use it or does he need to have acess to some factory / laboratories tools ?
Does an electrolytic gold surfacing has any interrest in audio (talking about an already populated board) ?
oil is too hard to stay cold ?
why not open a thread (if it has any interrest for audio of course)... it's off topic while staying a subject about a pcb DAC !
Does an electrolytic gold surfacing has any interrest in audio (talking about an already populated board) ?
oil is too hard to stay cold ?
why not open a thread (if it has any interrest for audio of course)... it's off topic while staying a subject about a pcb DAC !