TO3 metal can output transistors are more expensive than either TO3-P or TO247 types. There are really good, designed for audio output stage Sanken Japan types in TO3-P packages for less than half the price of On Semi TO3 types. I just bought some for $3.75 USD each. On Semi TO3 types are around $8.00 USD each at the usual distributors. It pays to do your research, especially when you have to buy quantities.
I admit TO3 devices all in a row look good and macho.
I admit TO3 devices all in a row look good and macho.
TO-3 are available New Stasis front end
and cheaper than TO-247 similar transistors New Stasis front end
Diyers can actually build version from post #1.
One more question:
Today only Mr. Pass know the revival Stasis nominal specyfications ?
Edit:Use of plastic TO-247 packaging is less metal work, but not big deal for me.
Anyways always nice to have different choices 🙂 Have fun
and cheaper than TO-247 similar transistors New Stasis front end
Diyers can actually build version from post #1.
One more question:
Today only Mr. Pass know the revival Stasis nominal specyfications ?
Edit:Use of plastic TO-247 packaging is less metal work, but not big deal for me.
Anyways always nice to have different choices 🙂 Have fun
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I think I have one rail each of MJL21193/21194. What sort of measurement/matching is advised?
Vbe, what else?
same approach as this, replace DUT mos for bjt
calc emiter resistor for , say, 200mA (0V65/0A2)
rotate polarities for pnp testing
you can go up with rail voltage, for increased correlation with actual circuit
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and - Toobz are Macho...
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Indeed! I like this one. It looks so BAD A$$ that it must be restrained to keep it from running away on its own.
🙂
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Board Needed
I'm currently upgrading by beloved s150 amp, After many years of service and replacing the main caps the DC off sets started to increase above 100 mv. I was going to change the amps in the front end. Then, there it was, NP added this post. I was in heavens.
However, I have try all the PCB manufactures listed in this post finding great discrepancies among the price. If any of you have figure this out and will like to sale me two boards or I can contribute in order to purchase larger quantities.
Experimental
First post. Long time reader of Nelson amp writing.
I'm currently upgrading by beloved s150 amp, After many years of service and replacing the main caps the DC off sets started to increase above 100 mv. I was going to change the amps in the front end. Then, there it was, NP added this post. I was in heavens.
However, I have try all the PCB manufactures listed in this post finding great discrepancies among the price. If any of you have figure this out and will like to sale me two boards or I can contribute in order to purchase larger quantities.
Experimental
First post. Long time reader of Nelson amp writing.
I will have 2 spare NP new Stasis FE pcbs, available - they should be here in a few days. Send me a PM if you want them.
...I was in heavens.
I hope, for your sake, that you haven't run into those annoying singing angels.
😉
The Peak Atlas DCA75 Pro tester is a handy device to test and match devices. For a BJT, it will tell you type of device, pin layout, HFE, VBE, VCEsat and IC leakage, all at 5mA. Handy for testing and matching a large number of devices. Of course ZM's circuit tests for VBE at 500mA.
New Stasis front end
Use 3 standoff per board instead 4 means 2 less metal parts (6pcs.for stereo not 8pcs.)
with practically the same mechanical performance a wise minimalistic touch
All this with PCB smaller size. Cool 🙂
Use 3 standoff per board instead 4 means 2 less metal parts (6pcs.for stereo not 8pcs.)
with practically the same mechanical performance a wise minimalistic touch

All this with PCB smaller size. Cool 🙂
The Sankens look interesting and aren't too expensive. Perhaps I'll get some to
play with.
Does anyone know what how many of the TO3P does Sanken put in a full rail? I'm
guessing 25 but I haven't found that info.
play with.
Does anyone know what how many of the TO3P does Sanken put in a full rail? I'm
guessing 25 but I haven't found that info.
Hi Dennis.
If you look at the Nakamichi PA-5 and PA-7 stasis designs by NP, you will see that Nakamichi used the 2SA1294 and 2SC3263 transistors. I bought 25 of each from Arrow Electronics with free delivery to here from their warehouse, Digikey also has them at a slightly higher price ( when I looked anyway)
They were delivered in rails of 12 and 13, obviously to cut down length for air mail. So I don't know what the standard Sanken rail length is - but is probably on their data sheets.
Sanken have a few candidates listed that can be used - all designed for audio.
If you look at the Nakamichi PA-5 and PA-7 stasis designs by NP, you will see that Nakamichi used the 2SA1294 and 2SC3263 transistors. I bought 25 of each from Arrow Electronics with free delivery to here from their warehouse, Digikey also has them at a slightly higher price ( when I looked anyway)
They were delivered in rails of 12 and 13, obviously to cut down length for air mail. So I don't know what the standard Sanken rail length is - but is probably on their data sheets.
Sanken have a few candidates listed that can be used - all designed for audio.
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2SA1294
https://www.semicon.sanken-ele.co.jp/sk_content/2sa1294_ds_en.pdf
Sanksen for 3~4 $ are the less expensive if copared to plastic TO-264 ON-Semiconductors ~8$
https://au.mouser.com/ProductDetail...A_ECIA_inventoryfeed_VSE&cmpProduct=MJL4281AG
TO-3 price ON-Semiconductors are in between..
Edit: They have not the same % of the output distorstion 🙂
https://www.semicon.sanken-ele.co.jp/sk_content/2sa1294_ds_en.pdf
Sanksen for 3~4 $ are the less expensive if copared to plastic TO-264 ON-Semiconductors ~8$

https://au.mouser.com/ProductDetail...A_ECIA_inventoryfeed_VSE&cmpProduct=MJL4281AG
TO-3 price ON-Semiconductors are in between..
Edit: They have not the same % of the output distorstion 🙂
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