who has the best audio driver

[prorms]

who do you think has the best audio driver?

 

[pinkmouse]

What do you mean?

 

[anatech]

Hi seanmacss,
Given you are posting in Solid State, I guess you mean driver transistors?

-Chris

 

[prorms]

just an example schematic


i have the audio drivers circle in red

example bd134 pnp 1.5 amps 80v 12.5 watts
bd139 npn 1.5 amps 80v 12.5 watts
mje15034npn 4amp 350v 50watts
mje15035pnp 4amp 350v 50watts


http://www.onsemi.com/pub/Collateral/BD136-D.PDF
http://www.onsemi.com/pub/Collateral/BD135-D.PDF
http://www.onsemi.com/pub/Collateral/MJE15034-D.PDF

 

[prorms]

i type an mistake
bd139
bd140

 

[anatech]

Hi seanmacss,
My personal favorites are the Toshiba devices they keep discontinuing.

If only the hFE of the On Semi devices weren't 2:1 for the PNP types.

-Chris

 

[AndrewT]

Hi,
I like 2sb649/d669
120Vce0 or 160Vce0(a), 20W, 1.5A, fT 110 to 140MHz, Cob 27pF, hFE 100 to 200 (C) or 160 to 320 (D).

Good performance for Vrail upto +-60V.
Struggles a bit with low impedance loads but does 4ohm and above very well.

and cheap!

 

[AndrewT]

Hi Seanm,
tr3 is the VAS and should be low Cob for drive from LTP.
tr7 is CCS. Not sure what speed you need here, having seen conflicting arguments.

2sc1360 makes a good VAS.

 

[jaycee]

For the schematic and outputs shown I'd just stick with the MJE15034/5 drivers and either BD139/140 or MJE340/350.

re VAS, I was looking at these Fairchild transistors -

http://www.fairchildsemi.com/ds/KS/KSC3503.pdf
http://www.fairchildsemi.com/ds/KS/KSA1381.pdf

What do you people think? They look like good VAS and predrivers in a triple darlington output stage to me.

 

[AndrewT]

Hi Jaycee,
the fairchild 2sa1381/c3503 have good specs to suit VAS duty.
Try to get E or F grade, matching grades for N & P types.
For high voltage types the specs hold up very well, most lose somewhere in exchange for this level of voltage tolerance.

 

[jaycee]

Yep I thought so too, and the best part is they are easy to buy directly from Fairchild themselves, and not too expensive!

Furthermore, they have SPICE models which so many japanese type transistors do not have.

 

[ACTIVA]

Hi Seanmacss,

MJE15030 & MJE15031 from ON Semiconductor are competent driver Transistors.
Proven track record, reliable, affordable and decent sonic.

Regards
Max