Thanks you for the very helpful replies.Much appreciated .
I have two similiar size heatsinks.
I am planning to do a cap multiplier based on either Rod Elliot or PMI schematic based on Mr Evil.
Originally, plan to use smps from Connexion but i donot see much response form Cristi in the forum.
kp93300
I have two similiar size heatsinks.
I am planning to do a cap multiplier based on either Rod Elliot or PMI schematic based on Mr Evil.
Originally, plan to use smps from Connexion but i donot see much response form Cristi in the forum.
kp93300
Seen from cost side you can't go wrong with CM because you already have transformer, and good reviews from members with this solution so starting up in this setup seems wise.
I read your post #2609 as having one 300W transformer, and it is okay with 8R speakers. If you have 4R or lower then a transformer with lower voltage and higher current is needed.
8R load 80W then voltage/current RMS ~25,2V/~3,15A at output.
4R load 120W then voltage/current RMS ~22V/~5,5A at output.
Good soldering.
Second VSSA PCB sets GB ending!
Hi
Some VSSA PCB sets were shipped last week, the rest will be send this week.
So the second group buy will be concluded this week and that's the promise. 😉
Happy assembling to all, enjoy the music. Regards, Lazy Cat
Hi
Some VSSA PCB sets were shipped last week, the rest will be send this week.
So the second group buy will be concluded this week and that's the promise. 😉
Happy assembling to all, enjoy the music. Regards, Lazy Cat
Lazy Cat, please PM-me the way to join you, you seem to have missed my various PM and emails.
![IMG_0660[1].jpg](/community/data/attachments/336/336750-5b63ca0b26b9a7e74c25e9d070b0f2f1.jpg?hash=W2PKCya5p-)
Can't hurt to make real measure that those power resitors read 22R no matter what is stamped on house.Hello again,
second channel soldered, behaves the same as the first,
maximum output bias 3.7V (168mA).
Lazy cat, any advice?
Regards
Marko
Hello Byrtt,
thanks for tip, I did that already. Unfortunately they are indeed 22R.
Regards
Marko
Power rails voltages ?Hello again,
second channel soldered, behaves the same as the first,
maximum output bias 3.7V (168mA).
Lazy cat, any advice?
Voltages at CCS outputs ?
Voltages across the two 10 Ohms of VAS ?
Power rails voltages +/-46V
Voltages across the two 10 Ohms R15 120mV / R16 -120mV
Voltages at CCS outputs -I would appreciate instructions where to take those measurements
Thanks
Marko
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Forget-it the VAS current are ok.
Now, no way to reduce offset by adjusting one or the other adjustable pots of the CSS near the input ?
Hi again Marko, small shoots easy/quick to do.
Measure R17 should read 604R, and check solder each end have connection down trace (belongs to TLVH431 Network).
Measure R18 should read 1K, and check solder each end have connection down trace (belongs to TLVH431 Network).
Solder pads for TR3 got connection all three ?
Should input be shorted ?.
Guess you can regulate at TR3 i.e. get lover than 3,6V over 22R ?.
BC550C/BC560C, KSA1381/KSC3503 reversed ?
Regards Ricky
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Excuse-me, i'm crossed against acronyms. What do mean DMM ?
Anything less than 5mV of total output offset whatever temp changes will be OK.
Hi Again Marko, small shoots easy/quick to do.
Measure R17 should read 604R, and check solder each end have connection down trace (belongs to TLVH431 Network).
Measure R18 should read 1K, and check solder each end have connection down trace (belongs to TLVH431 Network).
Should input be shorted ?.
Guess you can regulate at TR3 i.e. get lover than 3,6V over 22R ?.
BC550C/BC560C, KSA1381/KSC3503 reversed ?
Regards Ricky
Hello Byrtt,
As funny as it may sound I left modules at my workplace, I have more piece there than at home with a small child, I hope my boss is not a fellow member.
I will do the measurements first thing in the morning, and yes inputs should be shorted according to the manual.
I can indeed regulate TR3 lower than 3.6, initial value was 2.5, it would probably go even lower but I did not try that.
Thanks for assistance
Marko
Everything seems fine nice DC offset, 120mV over VAS device, nice build and no smoke 😉. So TLVH431 network is expected in my silly head.
Good evening and night, exited to hear when solution has been reached (curious)....
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As he have 168mA of quiescent, i believe everithing is perfect, TLVH431 side.
I have not understood if the offset problem was solved or not (he said 2mV). If not, and according the two amps behave the same:
Ocillation ? Bad ground reference ?
I was never having problems with DC offset, first module easily adjusted to 1mV on speaker outputs, second board -2mV. With a little effort I can probably zero DC offset completely, but I want to solve this output bias issues first.
Regards
Marko