Equiv. Parts: 2SD669, 2SB649

[Christer]

Originally posted by thanh

Are these models used for Multisim? I use Orcad.
Who can tell me the site to download multisim 2001 free ?

They're just standard Spice models, not for any Spice version
in particular. I've used them with both LTSPice and WinSpice and
they should work with any program conforming to Spice
standard.

[jmateus]

Yes, I told him so in an e-mail I sent congratulating him for
the exceptional design. Of course I told him so in a special way
but I believe he wouldn't be insulted anyway. At least he didn't
show it and subsequently I had a chance to discuss some other
stuff with him I he was always very nice... He is a gentleman,
you know!

[K-amps]

Originally posted by DSummer
According to the substittution handbook from Japan, B649/D669 can be replaced by A1011/C2344 or A968/C2238. If you really need the original transistors, just email me and LMK the quantity you need. May be I can help.

I have seen several Japanese amplifiers use the A1011/C2344 or A968/C2234 's as drivers. These include the Denon POA series amps and the Luxman M-117/ M-03 amps. They sound pretty good.

[sam9]

"B649/D669 can be replaced by A1011/C2344 or A968/C2238"

Just be sure have space for a TO-220 and to spin them 180 deg.

[K-amps]

Originally posted by sam9
"B649/D669 can be replaced by A1011/C2344 or A968/C2238"

Just be sure have space for a TO-220 and to spin them 180 deg.

Good point!

one should always know one's bearings while inserting..... a BJT ofcourse.

[thanh]

where are Slone living?

[ronwande]

I realize the last post to this thread was a while back. I built a Slone design amplifier, low power version using the BD139/140 as substitutes and the distortion was terrible. At 4 watts out of the 30 watt design target, at 1 KHz distortion was 1.5%

B&D Enterprises www.bdent.com has the 669 for 63 cents U.S.
They have the 649 for 83 cents.

I inserted them in my perf board wired amplifier and distortion at 4 watts went down to 0.005%, a reduction of about 300 times.

These results were without selecting any components. The output stage is a BJT emitter follower type. No sign of oscillation at the output with two pole compensation. Distortion at 20 KHz rises only to 0.0055% and to 0.0072% at 30 KHz. Response is flat 1o Hz out to about 70KHz.

The amplifier has just in the past day been brought to this point. Some 60 Hz interference prevents me from measuring distortion at lower frequencies precisely but it appears to be below 0.02% at 50 Hz.

I've looked over the data sheets of the BDs and the 2SBs extensively and I don't understand the reason for the dramatic improvement.

Ronwande

[jackinnj]

The 669/649 is a bit more robust -- while you may have been cooking the BD139's to the point of unhappiness -- ft and hfe are a bit higher as well.

[burbeck]

Hi there,
here are a couple of suppliers i find great here in the uk

http://www.dalbani.co.uk

http://www.cricklewoodelectronics.com

both the above have a wide range of semiconductors along with loads of other components at very reasonable prices. even on small quantity orders.
please note i have no connection with these companies other than being a very satisfied regular customer over many years.

regards
bob

[ronwande]

The driver transistors are on heat sinks which never seemed to get above body temperature so cooking doesn't seem to have been the problem. I've since fixed some issues with the wiring layout and brought distortion down a bit further. This is a continuing project.

I am going to be away for several days on a vacation trip, but I will report further some time later.