Patrick,
Please give a look to the table below, that is the best that I can get after matching 100 2SC and 2SA.
Not really lucky, I just have 16 2SA that can be somehow matched.
I think that they are matched enough (the worse are the CCS ones that are ~2,5% unmatched between NN and PP) but please let me know
Thanks and Regards,
Enrico
Please give a look to the table below, that is the best that I can get after matching 100 2SC and 2SA.
Not really lucky, I just have 16 2SA that can be somehow matched.
I think that they are matched enough (the worse are the CCS ones that are ~2,5% unmatched between NN and PP) but please let me know
Thanks and Regards,
Enrico
Attachments
Your best N-P matched pairs should be used for Q1,2 and Q7,8.
Then next best N-P match for Q11,12 & Q13,14 (Sanken).
Then NNN & PPP for Q4,6,10 & Q3,5,9, not must for perfect N-P match here (5% is OK, 2% is perfect).
And then next NN & PP for Q41~44.
But already mentioned in the PDF P.5 ??
Patrick
Then next best N-P match for Q11,12 & Q13,14 (Sanken).
Then NNN & PPP for Q4,6,10 & Q3,5,9, not must for perfect N-P match here (5% is OK, 2% is perfect).
And then next NN & PP for Q41~44.
But already mentioned in the PDF P.5 ??
Patrick
Thanks Patrick... yes, already mentioned.
I remember also that for the CCS the NN and PP should not be "unmatched" more that 5% and I am afraid that I have no matching for it.
Anyway I will redo the split as you suggest and see what's happen
Cheers
I remember also that for the CCS the NN and PP should not be "unmatched" more that 5% and I am afraid that I have no matching for it.
Anyway I will redo the split as you suggest and see what's happen
Cheers
The CCS is the least that matters.
It does not carry any signal, and is only essentially static (constant current).
You only need reasonable NN & PP.
The rest you trim out anyhow.
Patrick
It does not carry any signal, and is only essentially static (constant current).
You only need reasonable NN & PP.
The rest you trim out anyhow.
Patrick
Swap Q1,2 of left channel with Q7,8 of right channel.
Move Q43 of R Ch to Q43 of L Ch, Q43 of L Ch to Q44 of L ch.
Move Q44 of L ch to Q43 of R Ch.
Patrick
Move Q43 of R Ch to Q43 of L Ch, Q43 of L Ch to Q44 of L ch.
Move Q44 of L ch to Q43 of R Ch.
Patrick
Patrick,
It’s clear for Q43/Q44 moves
Not really for the first proposal “swap Q1, 2 of the Left with Q7, 8 of the right.
As far I understand Q1, 2, 7 and 8 should be matched as NN and PP as well and I was sure that my proposal was correct... what I miss? 🙂
Thanks for your patient 🙂
Regards,
Enrico
It’s clear for Q43/Q44 moves
Not really for the first proposal “swap Q1, 2 of the Left with Q7, 8 of the right.
As far I understand Q1, 2, 7 and 8 should be matched as NN and PP as well and I was sure that my proposal was correct... what I miss? 🙂
Thanks for your patient 🙂
Regards,
Enrico
Last edited:
Yes, that’s true... I was more focused to the NNPP matching.
Thanks for the clarification
Regards,
Enrico
Thanks for the clarification
Regards,
Enrico
Patrick,
Thanks for the heads up and fair warning about the difficulty of this project. Maybe I can use this as an excuse to pick up some new tools and knowledge 🙂
All of my matching is complete - Regulators are built and seem to be functioning perfectly. +/-14.54 almost completely across the board.
I’m almost wrapped up with the two SLA amplifier boards.
Is anyone able to give me the idiots guide to biasing the amplifier circuit? I’ve done a fair amount of reading through this thread and others on the forum and the closest I’ve gotten is to read the voltage across the emitter resistor - am I in the ballpark?
Thanks for the heads up and fair warning about the difficulty of this project. Maybe I can use this as an excuse to pick up some new tools and knowledge 🙂
All of my matching is complete - Regulators are built and seem to be functioning perfectly. +/-14.54 almost completely across the board.
I’m almost wrapped up with the two SLA amplifier boards.
Is anyone able to give me the idiots guide to biasing the amplifier circuit? I’ve done a fair amount of reading through this thread and others on the forum and the closest I’ve gotten is to read the voltage across the emitter resistor - am I in the ballpark?
> read the voltage across the emitter resistor
Yes. Voltage divided by resistance = current.
Make sure you use a large (over-sized) heatsink for testing.
Patrick
Yes. Voltage divided by resistance = current.
Make sure you use a large (over-sized) heatsink for testing.
Patrick
Hi. I'll order an other small batch of my Motherboard, one of the member wants it. So I'll probably end up ordering a few extra. Let me know if interested, same price as the previous GB. Thanks
SB
SB
Hi Patrick,
Somehow (arghh!) I missed to buy the ADA2202 for the protection board... I still have the OPA2209 from the previous protection board. I give a look to the datasheets and as far I can see (pin out and operating voltage) seems to be ok.
May I use the OPA2209 without changes on other parts?
Thanks and Regards,
Enrico
Somehow (arghh!) I missed to buy the ADA2202 for the protection board... I still have the OPA2209 from the previous protection board. I give a look to the datasheets and as far I can see (pin out and operating voltage) seems to be ok.
May I use the OPA2209 without changes on other parts?
Thanks and Regards,
Enrico
OPA2209 is fine up to 18V rails.
I only changed to the ADA because some projects like the UTHAiM or SL Transconductance need 24V rails.
Patrick
I only changed to the ADA because some projects like the UTHAiM or SL Transconductance need 24V rails.
Patrick
Patrick,
I took some time but I am there...
The 4 regulator are done, tested and trimmed the R1 to get:
+14.995 V
+15.006 V
- 14.934 V
- 14.973 V
The 2 main boards are tested:
- without CCS I get +61 and +42mV.
- with the CCS AND the 2 R44 trimmed I can get +4~+7mV and -3~-6mV
The SHPP is completed (and tested) and the chassis is work in progress 🙂
Regarding the passive Xfeed, if I am not wrong the 2 310K should should be installed. Can you please confirm?
What I need now is the motherboard to complete the PSU but I think it will take some weeks 🙁
I attached some picture... as you can see I was provident to buy the 2nd LEMO 😉
Enrico
I took some time but I am there...
The 4 regulator are done, tested and trimmed the R1 to get:
+14.995 V
+15.006 V
- 14.934 V
- 14.973 V
The 2 main boards are tested:
- without CCS I get +61 and +42mV.
- with the CCS AND the 2 R44 trimmed I can get +4~+7mV and -3~-6mV
The SHPP is completed (and tested) and the chassis is work in progress 🙂
Regarding the passive Xfeed, if I am not wrong the 2 310K should should be installed. Can you please confirm?
What I need now is the motherboard to complete the PSU but I think it will take some weeks 🙁
I attached some picture... as you can see I was provident to buy the 2nd LEMO 😉
Enrico
Attachments
> Regarding the passive Xfeed, if I am not wrong the 2 310K should should be installed.
Correct, if you are using 10k pot.
I doubt you will hear any difference even if you did install them.
> What I need now is the motherboard to complete the PSU but I think it will take some weeks
You should listen first, even with lab supply. 🙂
Patrick
Correct, if you are using 10k pot.
I doubt you will hear any difference even if you did install them.
> What I need now is the motherboard to complete the PSU but I think it will take some weeks
You should listen first, even with lab supply. 🙂
Patrick