Sunrise,
I downloaded the AD797 model from ADI
http://www.analog.com/en/DCcList/0,3090,759%5F%5F26,00.html
and it seems to model supply current correctly, in LTSpice.
If your model is also from ADI then we knew it's a bug of the simulator.
- Klaus
I downloaded the AD797 model from ADI
http://www.analog.com/en/DCcList/0,3090,759%5F%5F26,00.html
and it seems to model supply current correctly, in LTSpice.
If your model is also from ADI then we knew it's a bug of the simulator.
- Klaus
KSTR said:Sunrise,
I downloaded the AD797 model from ADI
http://www.analog.com/en/DCcList/0,3090,759%5F%5F26,00.html
and it seems to model supply current correctly, in LTSpice.
If your model is also from ADI then we knew it's a bug of the simulator.
- Klaus
WOW....thank You very much....nice....
peranders said:I doubt that AD797 is suitable for this but meanwhile have you checked the original design?
Bad copy
Better copy
I have made an amp similar yours but for headphones. Info here
This amp has been copied by a korean guy. Pictures here
Per-Anders - thankYou very much for replying...i can't open "better copy" link ...
PMA said:I already told him this by e-mail, when contacted.
Pavel, thank You for entering here - OPA627 that You have suggested is very expensive here in delta quadrant but it is one good opamp for sure....
how about to try NE5534...could this be more stable than AD797 ...also i can try OPA134 too that seems to have the same pinout as AD797...thank You again...
it is o.k. - no problem - thanks for the link
http://www.sjostromaudio.com/hifi_files/misc/AN211_better_text.pdf
i think that i will try NE5534 instead of AD797 for a start and than find some OPA134 and after that try OPA627 as a top amp for this ...
everything will be checked with osciloscope at the end....
could NE5534 be o.k. for a start...???
http://www.sjostromaudio.com/hifi_files/misc/AN211_better_text.pdf
i think that i will try NE5534 instead of AD797 for a start and than find some OPA134 and after that try OPA627 as a top amp for this ...
everything will be checked with osciloscope at the end....
could NE5534 be o.k. for a start...???
hi guys....i powered the beast up...i am using NE5534 in the input for now...
it seems to me that the sound of this amplifier is practically determined with the quality of the opamp...it is almost crucial to have a good opamp....am i right.....???
the schematic is in the post no.1
regards
sunny
it seems to me that the sound of this amplifier is practically determined with the quality of the opamp...it is almost crucial to have a good opamp....am i right.....???
the schematic is in the post no.1
regards
sunny
o.k. - this is the actual circuit that i am playing with...
instead of the NE5534 opamp i am using OPA627.....the power supply is +/-37Vdc ..... and i am using only one output pair of transistors for now...i will add another pair....
it is sounding quite nice.....
the question is what can be done better in this schematic....
i have few suggestions that might be done...
1. put 100nF capacitor accross c-e of BD139-16 transistor in the VAS section (or better to put 2 cap's - one accros b-e and one accros b-c)..???
2. instead of the resistor 6k8 in the input part of the amp - the one that is supplying current for the zener diode - put a ccs - would this make things a bit better....
i would like to make a better psu for the opamp using this sch...so, how can this be done that is the question...???
well....this is a brainstormer...
regards
sunny
instead of the NE5534 opamp i am using OPA627.....the power supply is +/-37Vdc ..... and i am using only one output pair of transistors for now...i will add another pair....
it is sounding quite nice.....
the question is what can be done better in this schematic....
i have few suggestions that might be done...
1. put 100nF capacitor accross c-e of BD139-16 transistor in the VAS section (or better to put 2 cap's - one accros b-e and one accros b-c)..???
2. instead of the resistor 6k8 in the input part of the amp - the one that is supplying current for the zener diode - put a ccs - would this make things a bit better....
i would like to make a better psu for the opamp using this sch...so, how can this be done that is the question...???
well....this is a brainstormer...
regards
sunny
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