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Once more Sansui transistor substitutions

The way I understand it is that fast devices used with appropriate circuit design, can swing (or slew) the amplifier output voltage, (fed to the speakers), very fast indeed and this ability allows them to 'follow' an input signal very closely = lower distortion/colouration.
 
Hyperion said:
The way I understand it is that fast devices used with appropriate circuit design, can swing (or slew) the amplifier output voltage, (fed to the speakers), very fast indeed and this ability allows them to 'follow' an input signal very closely = lower distortion/colouration.
Click to expand...
I think too it's in that line of thinking. But that would mean you have " to slow " and the right speed= it can keep up with the signal at the higher frequencies= fast.
Just doesn't explain why some comparable "slower" designs still sound so good, for example the au 517/717 or anything before the faster amps.
 
bubhardy said:
The human ear and brain are an amazing combination.
Perception is not always reality, also.
Click to expand...
I think you could say perception creates our own reality. Once I read that when in familiar place your visual input is just processed for about 10% the other 90 is filled in from memory. Explains why you can not find your keys at home your eyes see them your brain not. I think the same happens with listening. This would mean that when you listen to a piece of music, depending on your state of mind and focus, you can enjoy it or not not depending on sound quality that much.
 
GrisPato said:
I think you could say perception creates our own reality. Once I read that when in familiar place your visual input is just processed for about 10% the other 90 is filled in from memory. Explains why you can not find your keys at home your eyes see them your brain not. I think the same happens with listening. This would mean that when you listen to a piece of music, depending on your state of mind and focus, you can enjoy it or not not depending on sound quality that much.
Click to expand...
Agreed.
Mood affects perception.
So, this might explain it?
 
Skywatcher said:
Good Scotch affects everything.
Click to expand...
Now we're talking.
GrisPato said:
Just doesn't explain why some comparable "slower" designs still sound so good, for example the au 517/717 or anything before the faster amps.
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I couldn't say (that answer require some knowlege that I probably will never get)... I guess they are good desgins, with nice PS, shielding I can only guess.
GrisPato said:
And if I understand it the right way the use of fast transistors means the possibility of less distortion.( More negative feedback and more bandwidth)
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Yeah, That what I got plus headroom on the frecuency response seems to be a good thing.
 
Hello all , I’m a bit confused, if someone can help me it will be much appreciated!
I have a sansui au 555a and on the tone control I have the 2sc632A transistor , I’m thinking to replace them with either BC547C or BC550B
Is the 2sc632A a NPN or PNP or something else ;;;
As when I checking with my multimeter I get different respond between the 2sc and the substitute transistors that I suppose to put in the amp
Thank you in advance !
 
ARGOU said:
Hello all , I’m a bit confused, if someone can help me it will be much appreciated!
I have a sansui au 555a and on the tone control I have the 2sc632A transistor , I’m thinking to replace them with either BC547C or BC550B
Is the 2sc632A a NPN or PNP or something else ;;;
As when I checking with my multimeter I get different respond between the 2sc and the substitute transistors that I suppose to put in the amp
Thank you in advance !
Click to expand...
That's because the 2SC632A is a center Collector (Japanese), and the BC547/550 are center Base (European). The pinout is different. Check the datasheets to see what they are and you'll know which pin is what.
2SC and 2SD are NPN
2SA and 2SB are PNP
 
ARGOU said:
Hello all , I’m a bit confused, if someone can help me it will be much appreciated!
I have a sansui au 555a and on the tone control I have the 2sc632A transistor , I’m thinking to replace them with either BC547C or BC550B
Is the 2sc632A a NPN or PNP or something else ;;;
As when I checking with my multimeter I get different respond between the 2sc and the substitute transistors that I suppose to put in the amp
Thank you in advance !
Click to expand...

Search the transistor ID to get specs.
https://alltransistors.com/transistor.php?transistor=16869
 
Skywatcher said:
That's because the 2SC632A is a center Collector (Japanese), and the BC547/550 are center Base (European). The pinout is different. Check the datasheets to see what they are and you'll know which pin is what.
2SC and 2SD are NPN
2SA and 2SB are PNP
Click to expand...
Thank you for your time Skywatcher !
Make sense , I need to do a research !
 
JJCalvillo said:
Search the transistor ID to get specs.
https://alltransistors.com/transistor.php?transistor=16869
Click to expand...
Thank you JJcalvillo!
I ve checked that site and I always searching for specs in there , it’s pretty reliable, if we can say that .
Unfortunately the PDF/picture for the 2sc632
It’s in a very bad condition, impossible to read it !
As I know that the BC547/550 are CBE and the 2sc is BCE , if I “twist” the pins around , making sure not sorting of course, then I can use them.
To identify the pins .... is it the transistor cut edge facing me , starting from the the left to right , the BC’s should be CBE ? Or the cut edge facing down will be CBE ?
Sorry for the stupid question, it’s a bit news to me and please forgive my bad English !
 
 
Hyperion said:
https://www.web-bcs.com/transistor/tc/2sc/2SC632.php
https://transistordata.com/bjt/2sc632/get-datasheet
https://www.radiomuseum.org/tubes/tube_2sc632.html
https://pinout.net/element_browse.php?conid=30163

Is that enough? - do I need to go on?

As I said, pinout images and datasheets are ALL OVER the Very interesting Internet. :rolleyes:
Click to expand...

Yeah, I’d rather not respond to people who obviously haven’t done more than 5 minutes of googling for an answer.

I found this in literally 5 minutes using a Google image search.

AU555-transistors1.jpg


From https://audiokarma.org/forums/index.php?threads/sansui-au555a-and-pop-crackling-on-phono.843038/

Sorry for the distraction, just needed to say.

Now back to the ongoing saga of Sansui transistor substitutes already in progress.
 
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Ronito6 said:
Yeah, I’d rather not respond to people who obviously haven’t done more than 5 minutes of googling for an answer.
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And you shouldn't !!! And you didn't !!!
I only asked for one or maybe two transistors in any post I have made and the reason for this particular one was that I could only find a Japanese pdf in a bad photo ! So I assume that you might have something different coming up on your feed on Google search as you probably Google 10 transistors per hour maybe 50 in the weekend!
So it's not that I don't want to put the work in it . because of a different pin out I created a problem that I fixed after working on my amp for continusly 28 hours !
So yes , since the forum is here , I would ask and triple check too !!!
Any ways sorry for the disturbance in the thread, you can delete this post later so it's not interfering to your "ongoing saga of Sansui transistor substitutes "
 
Ronito6 said:
Yeah, I’d rather not respond to people who obviously haven’t done more than 5 minutes of googling for an answer.

I found this in literally 5 minutes using a Google image search.

AU555-transistors1.jpg


From https://audiokarma.org/forums/index.php?threads/sansui-au555a-and-pop-crackling-on-phono.843038/

Sorry for the distraction, just needed to say.

Now back to the ongoing saga of Sansui transistor substitutes already in progress.
Click to expand...
Cool.
Unfortunately, the 2SC2240 pinout on the picture is different from the ones I have.:rflmao:
 
gslikker said:
Cool.
Unfortunately, the 2SC2240 pinout on the picture is different from the ones I have.:rflmao:
Click to expand...
I’m this actual thread , further down the guy who started the thread , says that the picture is wrong ! The pin out is the same as the 2sc632a .
I still try to figure it , as tomorrow I have to replace the 2sc632a with the 2sc 2240 which mine is actually 2sc2240GR3J .... I need more research to see how will be plugged in !
 
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