2sa968/2sc2238

[Filburt]

Hi guys!

So, I have a few of these that I bought for use in my Cavalli-Kumisa-Kan III amp build, and am wondering if they were a particularly good choice. When I bought them I was under the impression that they do a good job, but after poking around with the forum search more it seems like people recommend some other stuff, so now I'm not so sure

[satoru]

2SA968/2SC2238 pair is used everywhere from DIY to commercial amplifiers. They were THE choice for driver Tr for so long time (more than 20 years). Now Toshiba offers different pair but 2SA968/2SC2238 is still available.

Have fun!

[AndrewT]

Hi,
good drivers, with limited SOAR when operating at high voltage.
Keep the PSU <=+-70Vdc if driving 8ohm speakers.
<=+-60Vdc if driving 4ohm speakers.

[h_a]

The Kumisa3 is a headphone amp, so no worries about rails!

Have fun, Hannes

[housing]

Originally posted by Filburt
Hi guys!

So, I have a few of these that I bought for use in my Cavalli-Kumisa-Kan III amp build, and am wondering if they were a particularly good choice. When I bought them I was under the impression that they do a good job, but after poking around with the forum search more it seems like people recommend some other stuff, so now I'm not so sure

I also used the Y version of the 2SA and 2SC instead of the BD's in my Cavalli-Kumisa-Kan III amp. No problem whatsoever.

Remember to solder them backwards as they have different pinouts from the BD's. Add a small heatsink for each of them to make them run cooler.

[Filburt]

OK! Thanks for the help, guys!

I'm wondering what I should use in the VAS. I was originally going to use 2SA970/2SC2240 but nelsonvandal recommended 2SA1016/2SC2362 instead. They seem like good transistors but I haven't seen anyone try them in this amp. Pretty tempting, though

[fotios]

Originally posted by Filburt
OK! Thanks for the help, guys!

I'm wondering what I should use in the VAS. I was originally going to use 2SA970/2SC2240 but nelsonvandal recommended 2SA1016/2SC2362 instead. They seem like good transistors but I haven't seen anyone try them in this amp. Pretty tempting, though

For VAS and CCS for VAS there is not better choice from:
MPS-U10
MPS-U60
or
BF460
BF463
Those offer: Vce=250-300V, Ic=500mA, Cob=3pF.
You can make a comparison with Toshibas.
Those are obsolete some years ago (when Motorola semiconductors turned in OnSemi) but you can find them in some online stores. There are in stock yet, and their price is about 6$.

Regs
Fotios

[homemodder]

Hi Filburt

The 2sa1016 and comp are along with two cousins it has, the best small signal transistors one can get, they outperform the toshibas easily and sound better too. Watch the current for use in a vas though.

[aparatusonitus]

What about NEC 2SC1845/2SA992 or Fairchild KSC1845/KSA992?

[CBS240]

Hi

I've used Fairchild's version of KSC1845/KSA992, well the SOT-23 version anyway. They are only rated 120V so you can use them with up to +/-55V PSU. IMO they make better VAS device then input pair. I like to have a faster transistor for the input pair. Also they can't take lots of current before the gain drops, a couple of mA. Decent noise figure though, might be better suited used as a VAS buffer in higher voltage amps....