NEC C2587 equivalent ?

[beppe61]

Dear Sirs,

I have a power amp with two pairs of output devices.
I can read only those marked NEC C2587 .
Maybe they are 2sc2587 ?
They look like Sanken tranistors.
I need to find some easily available equivalent (and its complementary as well).

Thank you very much indeed.

Kind regards,

beppe61

 

[jacco vermeulen]

Beppe,

Your NEC 2SC2587 are 120 watt devices.
10 amps, 150 volts, Ft of ~30 MHz, Hfe>100
I believe the complementary of the 2SC2587 is the 2SA1107.

Equivalent replacements were Toshiba 2SA1095/2SC2565 or Sanken 2SA1215/2SC2921, both 150 watt types.
For regular case normal type devices the Toshiba 2SA1301/3280 that i am using for four 6-device Leach boards have about the same stats. All obsolete too.

You can probably still find the NEC types at filthy expensive obsolete device places like Mark5.co.uk

More sensible maybe to try Sanken 2SA1216/2SC2922 or cheaper different case style Toshiba 1943/5200 or OnSemi MJL1302/3281.

 

[beppe61]

Beppe, Your NEC 2SC2587 are 120 watt devices.
10 amps, 150 volts, Ft of ~30 MHz, Hfe>100
I believe the complementary of the 2SC2587 is the 2SA1107.
Equivalent replacements were Toshiba 2SA1095/2SC2565 or Sanken 2SA1215/2SC2921, both 150 watt types.
For regular case normal type devices the Toshiba 2SA1301/3280 that i am using for four 6-device Leach boards have about the same stats. All obsolete too.
You can probably still find the NEC types at filthy expensive obsolete device places like Mark5.co.uk
More sensible maybe to try Sanken 2SA1216/2SC2922 or cheaper different case style Toshiba 1943/5200 or OnSemi MJL1302/3281.

Dear Mr. Vermeulen,

thank you greatly for your very kind and valuable support.
The bjts are in a Sanken like case (MT-200 ?).
I would like to explain my project (a very silly one I am afraid).
1) replace the existing bjts with higher grade ones (do you think that the Sanken 2SA1216/2SC2922 couple should be an upgrade? which are the absolute most powerful Sanken usable?)
2) disconnect the 2nd pair of output devices, using in this way just a single pair of the new bjts per channel.

Is this a stupid move? Should the bias be checked again?
I like very much the idea of just a very powerful pair of output devices per channel (but please do not ask me why).

Thank you very much indeed.
Kind regards,

beppe61

 

[jacco vermeulen]

Beppe,

here is a picture of the ones i mentioned.
The 2SA1216/2SC2922 are 200 watt models, used to be 150 watts a long time ago.
The one on the right is a 230 volts model, also 200 watts but has a more favorable SOA curve because of the higher peak voltage.
That should be the most powerfull multi-emitter device produced, afaik Sanken does not go higher than 200 watts.

The smaller MT200 one on the bottom was the advised substitute for the 2SC2587. In Japan a TO3P case is called MT100, 1 hole instead of 2, btw.

If you substitute only one MT200 you will be 3 amps current capability short compared to a pair of 2SC2587, 17 amps versus 2 times 10.
And 40 watts less max power, 200 versus 2 times 120 watts.
Members like Eva have confirmed how sturdy these devices are, thanks to a big die and a large flange area.
Best choice would be the 230volt 2SC3264 to have the maximum SOA compensation for using only one device.
The 1216/2922 will be easy to buy, the others not or for very high prices.

imo, the multi-emitter Sankens are the best output devices since i heard Dieter Burmesters 828 flaggships some 2 decades ago.
(and a very sympathetic guy, i'm fortunate to speak German so well, from the current CES pictures i see he is still doing ok)
Many seem to agree, you might give it a shot with your Zap approach.

Whether it is an upgrade you should decide for yourself, i think.
A great number here hold the view that high bandwidth and linearity of output devices is not necessary, or even undesired.
Others like Claus do, and even feel that output devices should not be in parallel.

 

[beppe61]

Dear Mr. Vermeulen,

thank you so much for your extremely kind and valuable as always reply.

>

Beppe, here is a picture of the ones i mentioned.
The 2SA1216/2SC2922 are 200 watt models, used to be 150 watts a long time ago.
The one on the right is a 230 volts model, also 200 watts but has a more favorable SOA curve because of the higher peak voltage.
That should be the most powerfull multi-emitter device produced, afaik Sanken does not go higher than 200 watts.

Very interesting indeed. So this should be the choice for the single pair mod, if I understand correctly.

> If you substitute only one MT200 you will be 3 amps current capability short compared to a pair of 2SC2587, 17 amps versus 2 times 10.
And 40 watts less max power, 200 versus 2 times 120 watts.

Thank you very much for this information.

> Members like Eva have confirmed how sturdy these devices are, thanks to a big die and a large flange area.
Best choice would be the 230volt 2SC3264 to have the maximum SOA compensation for using only one device.
The 1216/2922 will be easy to buy, the others not or for very high prices.

And this is a real pity. Anyway I record your advice.

> imo, the multi-emitter Sankens are the best output devices since i heard Dieter Burmesters 828 flaggships some 2 decades ago (and a very sympathetic guy, i'm fortunate to speak German so well, from the current CES pictures i see he is still doing ok).

If I understand correctly you liked the 828s very much and they used Sanken output devices of the same kind as those mentioned? If so it is a very strong recommendation.
The test bench is always the listening.

> Many seem to agree, you might give it a shot with your Zap approach. Whether it is an upgrade you should decide for yourself, i think.
A great number here hold the view that high bandwidth and linearity of output devices is not necessary, or even undesired.

This seems a little strange to me.
Maybe for stability reasons ?
I think that linearity is always a nice thing in amps, on principle.

> Others like Claus do, and even feel that output devices should not be in parallel.

On the contrary this statement could have some basis, expecially for people like me that have no possibility to match perfectly those output devices.

Dear Mr. Jacco, thank you so much for your kind and extremely helpful technical support.

Kind regards,

beppe61
ITALY

 

[jacco vermeulen]

liked the 828s very much and they used Sanken output devices of the same kind as those mentioned?

Correct.

Afaik, Dieter Burmester was the first to use ringemitter Sanken output devices in his 200 watt 828 monaural power amplifier in the early 80s in Europe.
At the time US manufacturers employed mainly Motorolas, Japanese amplifiers used these exotic devices, obtaining them in reasonable order numbers was very difficult.
The 828 was fast, had a high bandwidth, a dual powersupply per channel, and extensive analog/digital protection circuitry.
Dampingfactor could be altered , and a 2 ohm version was available.
The 850 model was fully symmetrical and employed a large number of Toshiba 2S1302/2SC3281 devices.

The Sankens have been produced all those years, have been used in the most exclusive amplifiers and still are.

 

[jacco vermeulen]

In case you are wondering about the model numbers:

Alike the tradition of Porsche for production type numbers and Ferrari did by using engine displacement and cylinder number, Dieter Burmester early type numbers stand for year and month of release.
The picture i posted is of the 828 MkII.

 

[beppe61]

Correct.

Afaik, Dieter Burmester was the first to use ringemitter Sanken output devices in his 200 watt 828 monaural power amplifier in the early 80s in Europe.
At the time US manufacturers employed mainly Motorolas, ...

Dear Mr. Vermeulen,

thank you very much indeed for the very interesting infos.
Burmester is a very well regarded brand in the high-end production.
If they use Sanken bjts they have to be something o special.

Thank you very much again.
Kind regards,

beppe61

 

[mjf]

old thread.........old amp.
burmester 850 more than 20 years old.