Superb low-level transistors ...

gentlevoice

Member
Paid Member
2007-10-20 7:46 pm
Denmark
Hi,

I am looking for superb low-level analog transistors - possibly better alternatives to:

2SC2240 & complementary A940
2SC1815
2SB737 & complementary from ROHM
2SC2570 (not exactly an audio transistor, but in some respects sounds outstanding, in my opinion)
2SC1775 & complementary A872
2SK170 & complementary SJ74

Anybody knows about superb sounding alternatives? Low voltages are fine (e.g. 30-50 VDC), max current capability can be low (e.g. 40 mA), low Cob, low noise - what I am looking for are transistors with a superb, balanced sound (both bipolars and FETs)....

Regards,

Jesper
 
A few alternatives to the Japanese transistors, which can be a real pain-in-the-**** to source here in the US.

On-Semi 2N4401/2N4403. Used them in a few phono stages and was very happy with the result.

Zetex ZTX694B and ZTX795A for line stages and amp input stages.

Fairchild's Japanese replacement line (KSA, KSB, KSC, and KSD)seems to be every bit as good as the Japanese originals. Been using a lot of KSA992's and KSC1845's. Compare these parts to the 2SA872 & 2SC1775.
 
2SC2570 ? Shocks !

If you like it fast, just for fun : 2SA1538S/2SC3953S
400MHz/120V in TO92, not to be confused with Sanyo's A1538/C3953 in TO220 jacket.
(but don't bother to look for a datasheet)
 

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gentlevoice

Member
Paid Member
2007-10-20 7:46 pm
Denmark
Hey Jacco,

Yups, the 2570 is a fast one ... very low Cob and extremely high Ft. I have used it e.g. in I/V converters from a DAC without filtering - in my opinion it sounds very good here.

Thanks for your tip about the transistors. Do you know where to source them?

And now I find that I have sufficient input to make a shortlist of interesting transistors for comparisons - so thanks for the suggestions!

Regards,

Jesper

:angel: :smash:
 
As i said, just for fun.
These devices are obsolete, i got them from various sources and with floating supplies there's no sense in keeping records.
You asked for superb small signal parts, not easy peasy sources.

A couple of weeks ago i seem to have blanked the stock of $2.95 V-grade 2SK389 dual JFETs at Sound & Light Electronics (.net) in Southern California.
I noticed they list the A1538S at 3 two-bits the piece.(haven't checked where to trace the 2SC complementary parts in quite a while as i already have plenty)
 

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gentlevoice

Member
Paid Member
2007-10-20 7:46 pm
Denmark
I checked the 2SK398's data sheet today. Looks like an interesting transistor yet I noticed that compared with the 2SK 170 it has somewhat less "stable" noise figure graphs. Have you compared these two?

Jesper

P.S.: just checked the Sound & Light etc. and they seem to have ample different types - thanks for the tip!
 
Fooling around with a Marcof ppa-1h (high gain version) MC head amp (9v battery powered), as it is a good way to get a listen to a complementary pair of bipolars, by subbing the given set into it's pre-exising circuit.

Bringing this thread back to life, as the Marcof has the mps6521/6423 single complementary pair, as the active devices.

For extra credits in the stupidity club...I'm thinking I might even socket the board, so I can play around with said Bi-polars even more efficiently.

I mean, who doesn't want a big random ka-boom in their system which launches custom skaanning drivers across the room?

So, any other advice on comp pairs of bipolars, to-92 style or thereabouts?

The marcof circuit
. (flaw - the 1000pf caps are actually 100pf)