I m testing opa810. Listened at low volumes and sounded very good.. need to test more with some known musics..
Ahaha...
I am guessing but get out the last feedback cap for the second 861in the Vunce's pcb 😉
Told you fellows but discrete the opa 861 as i/v then opa 1656 or ada 4627 as buffers are the great balls of fire...boum. TNT will aprove if he soldered yet 🙂.'
I am guessing but get out the last feedback cap for the second 861in the Vunce's pcb 😉
Told you fellows but discrete the opa 861 as i/v then opa 1656 or ada 4627 as buffers are the great balls of fire...boum. TNT will aprove if he soldered yet 🙂.'
My diy time has been very limited lately, but I will try replacing the second opa861 with another type when I get time.
Suggestions for the buffer opamp position? (Must be in SMD package)
Thanks!
Btw, this thread will keep the opamp industry in business, LOL 😀
Suggestions for the buffer opamp position? (Must be in SMD package)
Thanks!
Btw, this thread will keep the opamp industry in business, LOL 😀
Vunce, get out first the few pico feedback cap on the second 861 please :
As well, have you some Allen Bradley 100 to 150R resistors ? 1/8 or 1/4 W ?
The reversed 861 is neutral as buffer and not necessarilly mandated according the following stage. Typically a modern pre/amp doesn't need it but the following resistor after the I/V must be tuned if you use a standalone 861 !
Edit : try CEN/SEN design in smd package : just two transistors ! the J-Fe(s)t is enjoyable but the other non Jfet doesn't need sorting out and is very neutral ! again non mandatory in a normal cable length and a modern amp/pre . But if you use headphoness.... well ! you can also use your smd 861 and a soic 8 single channel 5 V for the buff : new TI's are cool... just guessing 😉 !
As well, have you some Allen Bradley 100 to 150R resistors ? 1/8 or 1/4 W ?
The reversed 861 is neutral as buffer and not necessarilly mandated according the following stage. Typically a modern pre/amp doesn't need it but the following resistor after the I/V must be tuned if you use a standalone 861 !
Edit : try CEN/SEN design in smd package : just two transistors ! the J-Fe(s)t is enjoyable but the other non Jfet doesn't need sorting out and is very neutral ! again non mandatory in a normal cable length and a modern amp/pre . But if you use headphoness.... well ! you can also use your smd 861 and a soic 8 single channel 5 V for the buff : new TI's are cool... just guessing 😉 !
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Ok, got it.
I have two set of I/V boards built, I’ll modify a pair following your suggestions.
That will make it easier to notice the difference in sound by comparing them.
Thanks 😉
I have two set of I/V boards built, I’ll modify a pair following your suggestions.
That will make it easier to notice the difference in sound by comparing them.
Thanks 😉
problem with sen/ce is you need another powersupply ! in your case if smd transistors only wanted I would choose something else compatible 5V but in your shoes a good soic/8 5V and wouala !
happy you like it ! 🙂 ! It makes the I/V job very well but less the buffer job : exactly the opposit of the ada 4627-1 !
But the cool thing is they both are single channels oaps so an eventual layout hack is not mandatory which can be a danger -oscillations?- with some fast dual oaps adapted for single use on the pcb !🙁
Thanks
Supress C10, and raise R8 to 700R. -till to 900R-
Try to hack R10 with a 1/8 W Allen Bradley of the same value. Don't use soldering with silver. You should notice a difference with headphones or good speakers and likes the tonal balance 🙂 !
Supress C10, and raise R8 to 700R. -till to 900R-
Try to hack R10 with a 1/8 W Allen Bradley of the same value. Don't use soldering with silver. You should notice a difference with headphones or good speakers and likes the tonal balance 🙂 !
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for +-12V and +-5V power supplies, it is a headache to me and to the small chassis.
will DC be provided by Switching after Low Noise LDO is not too bad idea?
will DC be provided by Switching after Low Noise LDO is not too bad idea?
Switcher w/filtering—> LDO regulator (TPS7Axx Or LT304X type)—> DAC board
Yes, this type of psu works very well.
For AC/DC switcher the Meanwell IRM series is nice.
For DC/DC switcher Murata MEJ2 and Meanwell DCWN03
Like Paddy mentioned, output filtering is highly recommended.
Thanks for the support
and could I know the power consumption of Miro's board?
I am planning to use LT3045 LDO for +-12V and +-5V, but it provides only 0.5V, is it enough?
Thanks again
and could I know the power consumption of Miro's board?
I am planning to use LT3045 LDO for +-12V and +-5V, but it provides only 0.5V, is it enough?
Thanks again
Yes.
100mA for 5v and 200mA for 12v is plenty.
You will need 4x TL3045 regs
A pair in series to get +/- 5v
Same for +/-12v
100mA for 5v and 200mA for 12v is plenty.
You will need 4x TL3045 regs
A pair in series to get +/- 5v
Same for +/-12v