thanh said:
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.
Mr. Slone's amplifier
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!
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!
Re: B649/D669
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.
DSummer said:
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.
"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.
Just be sure have space for a TO-220 and to spin them 180 deg.
sam9 said:
Good point! 😉
one should always know one's bearings while inserting..... a BJT ofcourse.
2SB649/2sD669
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
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
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.
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
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
Re cooking BD139/40
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.
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.
How about these drivers Fairchild's KSC2073 / KSA940 . Mugen hybrid amp is using it. Is it better than bd's 139/140?
the nte373 and nte373 seems to be exact replacements for both of these parts, Im already half way through a board using both of these parts what do you guys think??
Do you mean NTE373 and NTE374? I still have several of Mr Sloans boards for the Optimos and want to fill them. Are there any other discontiued parts I should be aware of?
Old thread, but google found it for me!
I have a subwoofer amplifier to fix, that has a 2SD669 and 2SB649.
One appears to have cooked itself, so I plan to replace them both.
Obviously, its a subwoofer amplifier, its a down firing woofer, and I'm not overly concerned about SQ.
So, what part can I use, that I can easily get here in Australia? I'd probably prefer TO220, just for the increased thermal mass....
Thanks!
I have a subwoofer amplifier to fix, that has a 2SD669 and 2SB649.
One appears to have cooked itself, so I plan to replace them both.
Obviously, its a subwoofer amplifier, its a down firing woofer, and I'm not overly concerned about SQ.
So, what part can I use, that I can easily get here in Australia? I'd probably prefer TO220, just for the increased thermal mass....
Thanks!
TO-220 is not compatible with the footprint of TO-126.
If you have supply rails less than 40V you can use BD139/140.
Other pin-to-pin replacements include the MJE340 and 350.
However not all specifications are the same and the parts may not be electrically compatible.
For most power amplifiers this should not be an issue as long as the device limits are respected. You need to work out if the devices can be directly substituted.
If you have supply rails less than 40V you can use BD139/140.
Other pin-to-pin replacements include the MJE340 and 350.
However not all specifications are the same and the parts may not be electrically compatible.
For most power amplifiers this should not be an issue as long as the device limits are respected. You need to work out if the devices can be directly substituted.
Base and emitter are reversed between the two, it's not the pad size.
Which means the heatsink tab ends up on the wrong side if the whole assembly goes on to a sink. You could do it with individual sinks.
If TO-220 parts work for you the 4793/1837 pair should be more than sufficient.
Which means the heatsink tab ends up on the wrong side if the whole assembly goes on to a sink. You could do it with individual sinks.
If TO-220 parts work for you the 4793/1837 pair should be more than sufficient.
both.
sell fakes. I have contacted both and neither can guarantee that they sell genuine items. They claim their items are new. They're fake man. Like most everything on ebay.
Sorry to bump up an old post.. but I am looking again for an equivalent to the 2SB649A and so I found this thread.. I think the NTE374 looks the closest I think but even that is a pain to get in the UK. I have to say I am confused because of this thread. Some of the suggestions make no sense i.e. they are not very close at all.
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