Some more stuffing has being going on.
For the RIAA is use Styroflex in the treble. I got exactly 11nF in both channels.
In the midrange i have 3 x FKP2 10 nF plus 3.3nF KP1830 for a total of 33.2nF, both channels the same, that is still 1%.
The smaller resistor is a Dale CMF55 non magnetic 9.09kOhm and the bigger one is a series connection of two Dale CMF55 for a total of 73.6kOhm.
For the servo i use LF411, that is a bit cheaper then the OPA134 and works as well.
I have to order more parts to finish.
For the RIAA is use Styroflex in the treble. I got exactly 11nF in both channels.
In the midrange i have 3 x FKP2 10 nF plus 3.3nF KP1830 for a total of 33.2nF, both channels the same, that is still 1%.
The smaller resistor is a Dale CMF55 non magnetic 9.09kOhm and the bigger one is a series connection of two Dale CMF55 for a total of 73.6kOhm.
For the servo i use LF411, that is a bit cheaper then the OPA134 and works as well.
I have to order more parts to finish.
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great, you guys are getting there!
yes, the vias need no filling....
ricardo, its strange, i didnt measure any offset and had your boards connected to my cartridge no problem, sounded nice........
6mV / 2kohm is 3 microamps, too much definitely.... this is roughly the base current of one of the transistors of the input stage. i would be surprised if one of them is broken, but you may want to verify that. is the offset positive or negative?
yes, the vias need no filling....
ricardo, its strange, i didnt measure any offset and had your boards connected to my cartridge no problem, sounded nice........
6mV / 2kohm is 3 microamps, too much definitely.... this is roughly the base current of one of the transistors of the input stage. i would be surprised if one of them is broken, but you may want to verify that. is the offset positive or negative?
Hello Joachim,
My apologies to you all, to kind of butt in on this excellent well developed thread. Joachim, could you possibly give me some help with Riaa Values.
I am building a variant of your MMP high Z.
I am going for a 2 stage approach with 75us passive eq after the first transconductance gain stage, and the remaining 318,3180 time constants in a second, similar, zero feedback transconductance gain stage.
Could you give me any pointers to the 318,3180 RIAA values that i can possibly scale appropriatly to suit my required gain.
Many thanks.
My apologies to you all, to kind of butt in on this excellent well developed thread. Joachim, could you possibly give me some help with Riaa Values.
I am building a variant of your MMP high Z.
I am going for a 2 stage approach with 75us passive eq after the first transconductance gain stage, and the remaining 318,3180 time constants in a second, similar, zero feedback transconductance gain stage.
Could you give me any pointers to the 318,3180 RIAA values that i can possibly scale appropriatly to suit my required gain.
Many thanks.
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Yes.... my calc gives me a lower value for the main R
73.5k must be in parallel with mirror output imp
Ricardo, the values of the RIAA components of R2 are a bit lower then in the original version. That comes in part because the input stage is not cascoded.
Velvet, i will check my data until tomorrow.
Here, as an example of a two stage transimpedance RIAA, the design of Mr.Evil.
I did not check the mathematics but i seems to come close.
Velvet, i will check my data until tomorrow.
Here, as an example of a two stage transimpedance RIAA, the design of Mr.Evil.
I did not check the mathematics but i seems to come close.
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I got more parts from Mouser and have stuffed the Paradise R2 more.
The electrolytics are Panasonic FR. That is a new line that has the same low ESR and high life time then the FM range. They look more compact, so this seems to be competition for Rubicon ZLJ that is a smaller version of ZL. Price is affordable. I also ordered some Dale RN60D.They are i size between RN55 and RN65, cost only 10 cents in small quantity and best, the are non magnetic ! Besides some J310, that are still on order, i can now finsih the boards.
The electrolytics are Panasonic FR. That is a new line that has the same low ESR and high life time then the FM range. They look more compact, so this seems to be competition for Rubicon ZLJ that is a smaller version of ZL. Price is affordable. I also ordered some Dale RN60D.They are i size between RN55 and RN65, cost only 10 cents in small quantity and best, the are non magnetic ! Besides some J310, that are still on order, i can now finsih the boards.
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paradise rev2
.... and another one is working! Le'Flu just sent me a message that his boards are up and running, at first turn-on. no sound check yet but that should come soon. he also provided some suggestions for improvement that i am implementing as we speak.
couple more confirmations and the group buy is good to go!
.... and another one is working! Le'Flu just sent me a message that his boards are up and running, at first turn-on. no sound check yet but that should come soon. he also provided some suggestions for improvement that i am implementing as we speak.
couple more confirmations and the group buy is good to go!
beautiful... please note you can also use the J109 for the j310, not sure if they are easier to get though...
Hello everybody,
i've got a question to our german fellas;
are there @ Bü.... or Re... LEDs i should order ?
Even so for the 1µF, what part i should choose ?
Especially @ Bü, there are so many...btw, what
footprint is recommended ?
Still so many questions.
@Ulf,
why don't you risk an ear ?
Have fun !
i've got a question to our german fellas;
are there @ Bü.... or Re... LEDs i should order ?
Even so for the 1µF, what part i should choose ?
Especially @ Bü, there are so many...btw, what
footprint is recommended ?
Still so many questions.
@Ulf,
why don't you risk an ear ?
Have fun !
The Leds are 3mm 2mA. You can order Osram, Knightbridge, whatever. I use Reichelt because they usually are in the lower price range. You can even order surplus from Pollin.
I use 1uF MKT from WIMA; also Reichelt. You have to watch the footprint. In the PSU there is an option, in the Phono part, not. 7.5mm is fine. EPCOS, RIFA, are other options. They perform more or less the same. If you want P-P use WIMA MKP4, they are the smallest.
I use 1uF MKT from WIMA; also Reichelt. You have to watch the footprint. In the PSU there is an option, in the Phono part, not. 7.5mm is fine. EPCOS, RIFA, are other options. They perform more or less the same. If you want P-P use WIMA MKP4, they are the smallest.
Benedetto, i know that you are stone old but spoon feeding ?
Here we go :LED 3MM 2MA GN - LED 3mm, low-Current, grün bei reichelt elektronik
Here we go :LED 3MM 2MA GN - LED 3mm, low-Current, grün bei reichelt elektronik
Here are 1uF with 7.5mm footprint :MKS-4 1,0µ - WIMA Polyester-Kondensator, 20 bei reichelt elektronik
Velvet, your question is not that easy to anwer. First study this :riaa backgrounder 5 - Opamp Examples