Hi Jan, Yes the lower ones have the molding compound splashed over the tab. The upper ones are totally clean.ACD said:Without having the answer, I would say that the ones on the bottom has a very poor molding quality
Also the lower ones have small indents that the upper ones do not have.
The lower ones do work in my amp but I will try the upper row also and listen to the difference.
Interesting in this connection is you specified MJE15032 and MJE15033 for the VAS in Krell clone. I would rather use something like the displayed Toshibas. Any reason for your choice?ACD said:I also notised those small dots from the mold
It could be interesting if you can hear any difference, however telling the difference may be impossible
If I don't hear any difference there is no point to bother.
Interesting in this connection is you specified MJE15032 and MJE15033 for the VAS in Krell clone. I would rather use something like the displayed Toshibas. Any reason for your choice?[/qoute]
The short answer:
No reason
The lang one:
There are two "reasons" why I used the MJE's. I have good experience with these, and they are the sort of devices that "could" have been used originally in the Krell
Regarding your listening test, I would still say that you need to have two amps (with different trannises) lined up in a blind listening test to even have a change to tell them apart
People has the tendensy to not be objective (but subjective), so if they think (or have been told) that this amp has better trannies, they would say that this sound better...
Jan,
You switched the u and the o in the last quote. Not really inportant to me.
I can try the MJE parts too as I have plenty of these.
Why bother with blind listening tests? I am am the only one listening to my amp. This machine is for listening pleasure so if I like it is is good to me regardless what visitors tell me or double blind listening tests reveal.
You switched the u and the o in the last quote. Not really inportant to me.
I can try the MJE parts too as I have plenty of these.
Why bother with blind listening tests? I am am the only one listening to my amp. This machine is for listening pleasure so if I like it is is good to me regardless what visitors tell me or double blind listening tests reveal.
Elso Kwak said:Hi, I have the impression the darker green ones (bottem line) are fake. Anyone?
Or did Toshiba change the molding compund at a certain point in time?
Lower row is fake (darker green colour)
burnedfingers said:Quote:
Lower row is fake (darker green colour)
No, the real proof will lie on the inside, not the outer color. I have had numerous transistors before the fakes came out that were darker in color.
I suggest taking one of each apart and looking at the guts.
Real proof for me is sound!
Interesting. I got some fake Toshiba 2SA1095's a while back that were lighter green compared to the real ones...
(top two rows are real, bottom row fakes)
A good indicator is oftern the quality of the pins. Are they similar between the two? the pins in the fakes above are very low quality & thin.
An externally hosted image should be here but it was not working when we last tested it.
(top two rows are real, bottom row fakes)
A good indicator is oftern the quality of the pins. Are they similar between the two? the pins in the fakes above are very low quality & thin.
Here is a picture of some 968/2238.
These are like +20 years old, i bought a 100 of them at the time.
Pic quality isnt really great, i must have been licking my camera again.
They are actually quite dark, as you can see the 2 far left have no scoring, all others have markings, high voltage versions look just as bad.
In those days i found it peculiar that average quality look of almost every japanese device was awfull, be it small signal or power device.
Not untill the last few remaining years of production appearance became better, before that i had devices of which the coding was often hardly readable.
I'd say the bottom ones are genuine, including the crappy edges,maybe you should question the upper row, Elso baby ?
Comparing a B version with a regular voltage type may not be fair, who's the supplier ?
These are like +20 years old, i bought a 100 of them at the time.
Pic quality isnt really great, i must have been licking my camera again.
They are actually quite dark, as you can see the 2 far left have no scoring, all others have markings, high voltage versions look just as bad.
In those days i found it peculiar that average quality look of almost every japanese device was awfull, be it small signal or power device.
Not untill the last few remaining years of production appearance became better, before that i had devices of which the coding was often hardly readable.
I'd say the bottom ones are genuine, including the crappy edges,maybe you should question the upper row, Elso baby ?
Comparing a B version with a regular voltage type may not be fair, who's the supplier ?
Attachments
Elso,
Color has nothing to do with it. I could show you both light and dark versions of the transistor. I suggest you take one of each apart and look at the die. Hint, Toshiba hasn't made some of these numbers for a few years. I just took apart a QSC amplifier that was manufactured before the 1302 and its mate were discontinued and the outputs were darker in color than some of the earlier versions. These were the real transistor not a fake.
Color has nothing to do with it. I could show you both light and dark versions of the transistor. I suggest you take one of each apart and look at the die. Hint, Toshiba hasn't made some of these numbers for a few years. I just took apart a QSC amplifier that was manufactured before the 1302 and its mate were discontinued and the outputs were darker in color than some of the earlier versions. These were the real transistor not a fake.
burnedfingers said:Elso,
Color has nothing to do with it. I could show you both light and dark versions of the transistor. I suggest you take one of each apart and look at the die. Hint, Toshiba hasn't made some of these numbers for a few years. I just took apart a QSC amplifier that was manufactured before the 1302 and its mate were discontinued and the outputs were darker in color than some of the earlier versions. These were the real transistor not a fake.
I used primarily my ears.......
The 1302 is one of which i was talking about.
I have seen 1302/3281's in any shade of black/green, with visible coding or numbers you need a magnifying glass with, and with 3 different type Toshiba logo's.
Both seen inside the familiar brand models as on the shelf.
If not for the original company order paper they came with, the numbers i have now look so good its suspicious.
Taking any one of these beauties apart seems a shame.
I have seen 1302/3281's in any shade of black/green, with visible coding or numbers you need a magnifying glass with, and with 3 different type Toshiba logo's.
Both seen inside the familiar brand models as on the shelf.
If not for the original company order paper they came with, the numbers i have now look so good its suspicious.
Taking any one of these beauties apart seems a shame.
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