Hello Bix,
I cant find an import option either..
So manual is the only option.
I have given the links in the bom, so you can click on a link and add required qty to the cart. keep on doing this for all parts. Although links open in different browser tabs, mouser cart will still have earlier added parts.
regards
Prasi
I cant find an import option either..
So manual is the only option.
I have given the links in the bom, so you can click on a link and add required qty to the cart. keep on doing this for all parts. Although links open in different browser tabs, mouser cart will still have earlier added parts.
regards
Prasi
Hello avtech23,
could you share your cart to bix, so its easier and all the hardwork is already done![]()
Done ;-)
I have some amplifiers according this topology. Usual values for idle current in the input stage (2N5401) are mostly between 0,5mA and 2mA and in the predriver stage (VAS stage) mostly between 10mA and 25mA.Old single supply topology no need DC protect![]()
I would like to try 10-15mA for the input stage and 30-60mA for the predriver stage for checking the change of sound character.
What are the steps for new calculating for the resistor values?
Thank you for reply.
The VAS current will determine the singleton "input" transistor standing (and dynamic) current requirement. You will most likely have to "scale" all resistors around the input transistor. AND the "nfb" cap; and the "input" cap. AND the bootstrap cap if your amp has one....
Usual values for idle current in the input stage (2N5401) are mostly between 0,5mA and 2mA and in the predriver stage (VAS stage) mostly between 10mA and 25mA.
I would like to try 10-15mA for the input stage and 30-60mA for the predriver stage for checking the change of sound character.
...
For inspiration, look up some OLD 4-transistor (with "naked" BJT-pair at output) car-radio amps (usually with BD433/BD434 output pair; or AD161/AD162).
These amps ran with higher VAS current (some at 30-40ma) - and you can get the feel for the rest of the passives values. Also note that the singleton "input" transistor's reflected-dynamic-impedance at the emitter (here the "-" diff input a.k.a the "nfb" input) will drop almost proportionally to the rise in current demand; and the "nfb" gain cap will have to be really big this way.
The sound with higher standing current is imho more "forced" than with lower currents. I personally wouldn't go over 5ma in the "input" transistor.
Thanks Bix for confirming the receipt. and avtech for kind words.
Jan, I will be a bit late to the party as some components are on a slowboat from China. if you want to have a crack at it, let me know. its the Apex AX6 we are talking about and not the Autona AL125. Waiting for thimios to make some progress on that, but seems to have his fingers in too many pies (amps) at the moment.
regards
prasi
Jan, I will be a bit late to the party as some components are on a slowboat from China. if you want to have a crack at it, let me know. its the Apex AX6 we are talking about and not the Autona AL125. Waiting for thimios to make some progress on that, but seems to have his fingers in too many pies (amps) at the moment.
regards
prasi
ok, thimios has a set in the mail. lets see if Mr. DIY finds a bit of time to build this too.
Hi Prasi, packet received, i will try to built this soon!
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