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Yes, plenty of choices: p Rogic, T Loesch (tubes), Pass, Jocko Homo, Patrick (commercial pcbs at ZEN), Moglia hybrid emitter follower, etc.
Wondered only if Zen Mod had made a little buffer that recaptur the Yamaha/Sony beloved transistors hack he usually designs for his PassAmps... but for a discrete dac buffer.
Among that I believe Miro wants to follow his philosophy : trough hole and opamps for the masses and at worst soic opamp, but all in one i.e. I/V and buffer. For the tda 1541A the choice is the opa861 10 years ago Pedja Rogic's...semi public design.
Edit: if the pcb space is also wanted then instead of two oaps each per channel, I would consider two dual opa but first for the I/V then the second dual for the buffer. For instance opa 1602 then opa1656... just to keep it simple per Miro1360 roadmap... But 861 is just better...old story.
Wondered only if Zen Mod had made a little buffer that recaptur the Yamaha/Sony beloved transistors hack he usually designs for his PassAmps... but for a discrete dac buffer.
Among that I believe Miro wants to follow his philosophy : trough hole and opamps for the masses and at worst soic opamp, but all in one i.e. I/V and buffer. For the tda 1541A the choice is the opa861 10 years ago Pedja Rogic's...semi public design.
Edit: if the pcb space is also wanted then instead of two oaps each per channel, I would consider two dual opa but first for the I/V then the second dual for the buffer. For instance opa 1602 then opa1656... just to keep it simple per Miro1360 roadmap... But 861 is just better...old story.
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Of course...as the price, you can not hqve a Porsche at the price of a Ford ! There are more Skill in the commercial but the diy is really good, better than all and most semi conductors diyers tries here and already beat many NOS and delta sigma. At least my Audial Aya is one or two steps above the ad1862 here...not the same price either cause more complex front end and powersupplies. But the layout skill is making the difference, of course. It is the daily Job of Pedja Rogic, so not a fair comparaison.
Miro's offer is just nice and generous for diyers and all the advices of the fellows in the thread help also to lift up the design sounding result imho.
Miro's offer is just nice and generous for diyers and all the advices of the fellows in the thread help also to lift up the design sounding result imho.
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yep that's one in my aya2Yes, plenty of choices: p Rogic, T Loesch (tubes), Pass, Jocko Homo, Patrick (commercial pcbs at ZEN), Moglia hybrid emitter follower, etc.
Wondered only if Zen Mod had made a little buffer that recaptur the Yamaha/Sony beloved transistors hack he usually designs for his PassAmps... but for a discrete dac buffer.
Among that I believe Miro wants to follow his philosophy : trough hole and opamps for the masses and at worst soic opamp, but all in one i.e. I/V and buffer. For the tda 1541A the choice is the opa861 10 years ago Pedja Rogic's...semi public design.
Edit: if the pcb space is also wanted then instead of two oaps each per channel, I would consider two dual opa but first for the I/V then the second dual for the buffer. For instance opa 1602 then opa1656... just to keep it simple per Miro1360 roadmap... But 861 is just better...old story.
I need to try Nelson D1 ,in a wizard on analogOf course...as the price, you can not hqve a Porsche at the price of a Ford ! There are more Skill in the commercial but the diy is really good, better than all and most semi conductors diyers tries here and already beat many NOS and delta sigma. At least my Audial Aya is one or two steps above the ad1862 here...not the same price either cause more complex front end and powersupplies. But the layout skill is making the difference, of course. It is the daily Job of Pedja Rogic, so not a fair comparaison.
Miro's offer is just nice and generous for diyers and all the advices of the fellows in the thread help also to lift up the design sounding result imho.

PS.this days only Purosangue
Why avoid TL431? In this example with TDA1541, it will certainly be better than the LM78/79 or any other serial regulator. It is true that the TL431 has a lot of noise (that's why polymer caps are used),but it has low dynamic impedance and can handle up to 100mA of current, which is enough for TDA1541. There are better solutions than the TL431, but they are not so simple anymore and then we can already talk about Salas or Walt Jung shunt regulators which are TOP for powering digital especially DAC and filter ICs....I will avoid TL431 ref for the 3 TDA1541A rails ...that is antic design. I will however keep the idea of the CCS but with a filtered diode as a ref and an emitter follower with no resistor feedback and just a hf decoupling at the main voltage tda1541a and a very carrefully chosen cap as filtering smoothing cap.. Saying that I am surenthese advices will not be followed here, lol! I also will avoid Oscons and even more the newest one, and absolutely avoid the sepc and sepf...if the antic religion is your, you eventually can take the less bad sep serie, but it is colored...
Of course the DEM decoupling should have low inductance... means rigth to the legs of the dac chip. Despite its mkt and not mkp blah, I would give a try to the 2.5 mm pitch wimas mkt. It is just to stay through hole because there is better smd solution there. For the standalone Dem clock cap, mkp or silver mica is mandatory if through hole, in this case Fkp2 (non metal) is just the rigth thing to do.
And of course to stay cheap but good sound I will follow the little around oap and i/v ref I advised before in the thread for the ad1862 than noone tried despite the extensive test on a sota transparent speakers.
I will sqy nothing about the ground layout as I know I will be not heard too, ahaha, lol, aha, etc ! 😉 🙂
Polymer (OS-CON) or tantalum are used around digital because they cope better with RF noise than ordinary wet caps. 1 and 0 in digital signal certainly don't know which capacitor is in the decoupling, polymers can only remove additional digital noise or jitter, so on account of that we can say that maybe they color the sound, and now whether someone will like it or not is some other topic. Otherwise, I use OS-CON only in digital, they are useless in analog circuits.
Some 10 years ago I took a whole day apart and tested a bunch of capacitors for decoupling of the PMD100, without a hearing test, just with an oscilloscope, and OS-CON proved to be the best for the RF noise, which for the PMD100 is around ~5MHz when in 'mute' or ~12MHz in work. After this test, I only use polymer for digital and I don't worry at all about how it will sound because I know that with OS-CON I have the best decoupling as far as frequencies in the MHz range are concerned.
Normally, there is always an SMD COG or X7R right next to the power supply pin of the digital(analog) IC itself, but the electrolyte must also help if it is chosen well, otherwise there is no point.
It also makes no sense to use big TH film capacitors for those frequencies which I agree with, only maybe FKP2 or even TH MLCCs for TH lovers .
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I have the tl431 at analog stage. Yes that low impedance is its plus. The soic package version is said a little better than the through hole.
Will be surprise Miro is messing with such designs, although he talked about a discrete. Elvee thread with Trileru work is a plus with the simple lm317 and few parts.
I do not like ceramic class II and Panasonic just launched acrylic smd caps to swapp its PPS range...that is my choice...but it is not tht. So here the exercice is to stay tht and low inductance...below the 5mm pitch when feasible imo... Miro's roadmap ask for KISS and Tht anyway.
Will be surprise Miro is messing with such designs, although he talked about a discrete. Elvee thread with Trileru work is a plus with the simple lm317 and few parts.
I do not like ceramic class II and Panasonic just launched acrylic smd caps to swapp its PPS range...that is my choice...but it is not tht. So here the exercice is to stay tht and low inductance...below the 5mm pitch when feasible imo... Miro's roadmap ask for KISS and Tht anyway.
Another one lives! I finished it up on Friday evening but didn't get a chance to spend some time with it until today. And I like what I'm hearing 🙂. I'm using a DIR9001 based spdif receiver board and a Pi running Moode upstream from that. No boutique or fancy parts. Although I went with the datasheet minimum of 1uf/10uf for the noise reduction caps, as Wima makes MKS caps in these values small enough to fit the board's footprint. Currently using OPA1655 for I/V but would like to try one of the discrete options out there. Thanks to Miro for putting this together. And Paddy for supplying the chips. I'll definitely have to come up with a better enclosure because this one is not doing Miro's DAC justice!
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The PSU for TDA1541A ends up as a separate PCB 🙂 There is zero chance of doing any "best" PSU from my side.
I found only one nice testing of different PSUs: https://docplayer.net/154771090-A-c...y-regulator-designs-with-listening-tests.html
and that is why I created my PSU 2 PCB (LT1963A/LT3015). Also the shunt regulator (with mosfet) was not amaze in this article (because phase is rotated from 1kHz? ... not sure). Sad that the 78/79xx were not included 🤣
Simple shunt with ccs from bjt+LED (instead of mosfet) can be a nice candidate for my PSU 3, it is very linear with low impedance, although not very noiseless 🤔
I found only one nice testing of different PSUs: https://docplayer.net/154771090-A-c...y-regulator-designs-with-listening-tests.html
and that is why I created my PSU 2 PCB (LT1963A/LT3015). Also the shunt regulator (with mosfet) was not amaze in this article (because phase is rotated from 1kHz? ... not sure). Sad that the 78/79xx were not included 🤣
Simple shunt with ccs from bjt+LED (instead of mosfet) can be a nice candidate for my PSU 3, it is very linear with low impedance, although not very noiseless 🤔
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Use psu 1 or 2 for + and -,5V half one for the -15v...problem solved.
Or use led or zener with a Darlington as emittet follower...pb solved.
Or use led or zener with a Darlington as emittet follower...pb solved.
may I ask normally how many gain
the ad1862 dac chip provide 1ma current, using 50ohm IV resistor, 50mv output signal will be provided. If 1.5vrms output required and using ecc88, which Vdc value of HT anode supply and ohm value of cathode resistor, the 6.3Vdc of filament provided.
Thank so much
Happy
Hi grunf,Hi @happylistening
Try the ECC88 instead, the 6N6 has a lower gain and is better as a buffer or line stage.Then the supply voltage will be lower (180V). I recommended the same to Vunce.
You can make a simple power supply or regulator according to this scheme, the sum of the zener diodes should be approximately the output voltage (Vzener=Vout + 4V) , I made it on a small PCB with smd resistors, the DN2540 can be in a TO92 case. M1 can be any n-mosfet for voltages higher than 400V and for lower currents .This reg is made for the ECC88 in my DAC.
You can also add protection diodes to M1 and a film cap of 2.2uF (or similar) to the input of the regulator.
the ad1862 dac chip provide 1ma current, using 50ohm IV resistor, 50mv output signal will be provided. If 1.5vrms output required and using ecc88, which Vdc value of HT anode supply and ohm value of cathode resistor, the 6.3Vdc of filament provided.
Thank so much
Happy
https://www.firstwatt.com/pdf/art_zen_iv.pdf
Do you understand the limitations of that seemingly simple circuit, apart from output coupling caps ?
What output voltage should you expect with 1mA input current ?
How to make it output 2.8V with 1mA ?
And how can you improve its PSRR ?
Cheers,
Patrick
Do you understand the limitations of that seemingly simple circuit, apart from output coupling caps ?
What output voltage should you expect with 1mA input current ?
How to make it output 2.8V with 1mA ?
And how can you improve its PSRR ?
Cheers,
Patrick
50ohm I/V resistor and current +-1mA, then you have max. 100mV PP equal to 35mV RMS at the output. You will need a lot of voltage gain to get to about 2V RMS (57x). For that you need something like ECC83, ECC81, 6N2P...may I ask normally how many gain
Hi grunf,
the ad1862 dac chip provide 1ma current, using 50ohm IV resistor, 50mv output signal will be provided. If 1.5vrms output required and using ecc88, which Vdc value of HT anode supply and ohm value of cathode resistor, the 6.3Vdc of filament provided.
Thank so much
Happy
Could it be 150 ohm I/V resistor without too much THD? Then ECC88 and the like can come into play. My recommendation is to have a gain stage and a cathode follower behind it so that the output impedance is low.
SRPP and Mu follower options are also possible for the output stage. 6N6P in Mu follower has gain 20x, and E88CC 32x approximately.
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