BC560B instead of BC560C?

[endia]

Hi,
i'm building discrete diamond buffer for pmillett hybrid headphone amplifier.. this is the buffer's schematic;
http://www.diamondstar.de/dDB_isb_v022_schem.jpg

in the part list BC560C is suggested alternate part for Q2, Q4, Q6 and BC550C for Q3, Q5, Q7..

but

before soldering, i just realized that i have 560Bs not 560C.. may i use "B" type without any problem or should i buy "C" type..

thanks in advance..

 

[aparatusonitus]

You can use B grade transistors without problems, but performance of C grade will be somewhat better...also BC550/560 are so cheeeeep , so if I were you I would buy C grade.

 

[CBS240]

Hi

If you look at the datasheet for BC560, you will notice that the only thing the B or C designates is current gain (Hfe). The B is the lower gain class. Since in the circuit they are used as a mirror, I don't think it will make a difference. The (rather large ) 220 Ohm degeneration resistors will reduce thier gain anyway. If you can match them to a decent degree, or use a "matched" transistor array, you can reduce the degeneration. If the PS voltage is less than +/-15V, the BC559 would work too.

 

[endia]

CBS240, aparatusonitus, thanks for the quick replies..
i have not enough transistors for matching on hand and i think matched 560Cs will be best way..