Hey guys so I got an older American Bass car audio amplifier I am wanting to upgrade some of the older components in. Looking for some recommendations for what to use as replacement. So here is what I am wanting to replace.
NJM4558L these are the straight line pin opamps not dual inline
C4467 transistor
A1694 transistor
FMG22R diode?
IRFZ44N power mosfet
Any help is appreciated. I am also replacing the capacitors on the board as well and was curious as to the effects of increasing the capacitance rating. Right no it has 2200 and 1000 microfarad caps in it.
There are 2 dip chips on this board one is a pwm controller TL494CN and the other is an opamp 4558C.
Would there be any benefit to replacing those.
NJM4558L these are the straight line pin opamps not dual inline
C4467 transistor
A1694 transistor
FMG22R diode?
IRFZ44N power mosfet
Any help is appreciated. I am also replacing the capacitors on the board as well and was curious as to the effects of increasing the capacitance rating. Right no it has 2200 and 1000 microfarad caps in it.
There are 2 dip chips on this board one is a pwm controller TL494CN and the other is an opamp 4558C.
Would there be any benefit to replacing those.
Replace all the electrolytic caps, but leave all else alone.
Yes, you might be able to go higher on capacitance (but keep the voltage the same) in the power supply stages if they still fit the board, but only if you know what each cap's purpose is.
Use known brands from known suppliers for the caps.
Yes, you might be able to go higher on capacitance (but keep the voltage the same) in the power supply stages if they still fit the board, but only if you know what each cap's purpose is.
Use known brands from known suppliers for the caps.
High gain 4558 are hissy. At low gain, not so bad. Gain =Rf/Ri
The hissy ones I replaced were gain 50, but mag phono is not used in cars.
Not a lot of choice in SIP package op amps. The only datasheet I have that shows SIP is 4558.
I agree on the e-caps if over 5 years old. This is a consumer product, they probably did not use long life grade. I find e-caps rated >3000 hours service life have been superior in all the applications I've used them as replacements. Known brands are Nichicon, Rubicon, Panasonic, but all make cheapo and long life caps. Buy the long life ones.
Acceptable performance caps but shipping from a country known for lies on QA paperwork, have been United Chemicon, CDE, Multicomp.
Like everything else electronic on E-bay or alibaba, name on the part may be added after manufacture by the reseller. Buy from a known distributor to get genuine recent manufacture e-caps. For e-caps I use Newark (farnell US) mouser and digikey. And I'm the kind of guy who will recycle old plastic film caps out of old TV's I find on garbage day. Not e-caps.
The hissy ones I replaced were gain 50, but mag phono is not used in cars.
Not a lot of choice in SIP package op amps. The only datasheet I have that shows SIP is 4558.
I agree on the e-caps if over 5 years old. This is a consumer product, they probably did not use long life grade. I find e-caps rated >3000 hours service life have been superior in all the applications I've used them as replacements. Known brands are Nichicon, Rubicon, Panasonic, but all make cheapo and long life caps. Buy the long life ones.
Acceptable performance caps but shipping from a country known for lies on QA paperwork, have been United Chemicon, CDE, Multicomp.
Like everything else electronic on E-bay or alibaba, name on the part may be added after manufacture by the reseller. Buy from a known distributor to get genuine recent manufacture e-caps. For e-caps I use Newark (farnell US) mouser and digikey. And I'm the kind of guy who will recycle old plastic film caps out of old TV's I find on garbage day. Not e-caps.
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Because besides getting les hiss Op Amps, which would be the only true "improvement" achievable, replacing other parts you mentioned will improve nothing.
Non designers vaguely think "all designs are the same", just some use "better parts" (meaning expensive/exotic/obsolete) and other use "cheaper parts" (meaning bad parts) , and that they can go from a poor product to a good/better one just by replacing parts.
Sadly, it´s not that easy .
In general, a better product has a better design, has been extensively tweaked until best possible result has been achieved, modded/redesigned until acceptable.
As a made up example but to make clear the idea behind why I say it:
* is gold "better" than lead?
Most will answer "yes, of course, what a stupid question !!!! "
* Ok, then a fishing sink made out of solid gold is better than one made out of lead?
* "Hmmmmm, I suppose so"
With which I agree, at least on some point, it will last much longer, in 300 years it will be exactly the same while lead will be covered in whitish oxide or carbonate.
It will still work as a fishing sink though.
* will it help catch more fish than a lead one? (which is its actual purpose)
I very much doubt so.
* will your friends envy you and comment: " hey!! , look at Joe´s gold made fishing sink, what a cool guy he is".
Probably
Which for some is motivation enough
Non designers vaguely think "all designs are the same", just some use "better parts" (meaning expensive/exotic/obsolete) and other use "cheaper parts" (meaning bad parts) , and that they can go from a poor product to a good/better one just by replacing parts.
Sadly, it´s not that easy .
In general, a better product has a better design, has been extensively tweaked until best possible result has been achieved, modded/redesigned until acceptable.
As a made up example but to make clear the idea behind why I say it:
* is gold "better" than lead?
Most will answer "yes, of course, what a stupid question !!!! "
* Ok, then a fishing sink made out of solid gold is better than one made out of lead?
* "Hmmmmm, I suppose so"
With which I agree, at least on some point, it will last much longer, in 300 years it will be exactly the same while lead will be covered in whitish oxide or carbonate.
It will still work as a fishing sink though.
* will it help catch more fish than a lead one? (which is its actual purpose)
I very much doubt so.
* will your friends envy you and comment: " hey!! , look at Joe´s gold made fishing sink, what a cool guy he is".
Probably
Which for some is motivation enough
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