Hi to everybody.
I'm making the Aleph P1.7 right now but i'm tring to find also the parts for the next steps.
I wanna build the Aleph ONE but here is the issue:
i'm missing the 2SK389BL and i don't know where to find it for a reasonable time.
Is there any suggestion where i can find about 80-100 of it?
I don't know if i'm wrong but Nelson told on one of his thread that 2SK370 would be a good replace.
Since i'm trying ahead of time to find all the parts for the future projects, another part that i'm missing is the MPS 18 (i wanna also build the Aleph X too).
Any good replacement for this part? would it be necessary to find this exact part inn order to correctly build the ALEPH X?
Any good advice are welcome
🙂
Best,
Stefano.
I'm making the Aleph P1.7 right now but i'm tring to find also the parts for the next steps.
I wanna build the Aleph ONE but here is the issue:
i'm missing the 2SK389BL and i don't know where to find it for a reasonable time.
Is there any suggestion where i can find about 80-100 of it?
I don't know if i'm wrong but Nelson told on one of his thread that 2SK370 would be a good replace.
Since i'm trying ahead of time to find all the parts for the future projects, another part that i'm missing is the MPS 18 (i wanna also build the Aleph X too).
Any good replacement for this part? would it be necessary to find this exact part inn order to correctly build the ALEPH X?
Any good advice are welcome

Best,
Stefano.
2SK389 is obsolete. Replacement dual FET is LSK389 (not pin compatible) from Linear Systems. You can try to ask for samples.
MPSA18 :
http://www.musikding.de/product_info.php?cPath=60_76&products_id=721&language=en
or just use BC550 as replacement.
Patrick
MPSA18 :
http://www.musikding.de/product_info.php?cPath=60_76&products_id=721&language=en
or just use BC550 as replacement.
Patrick
yes...i heard about the lsk but it's too expencive.
The price of this is around $10 per part....waayyy tooo much for a fet.
I woud like to know if there are fet compatible that i can use as a good replacement for this part.
Nelsooonnn pleeeaaseee help!!!
What part could we use? 😕
The price of this is around $10 per part....waayyy tooo much for a fet.
I woud like to know if there are fet compatible that i can use as a good replacement for this part.
Nelsooonnn pleeeaaseee help!!!

What part could we use? 😕

Hello Stefano,
in Italy you can find the 2sk389 here: http://www.lelettronicaasti.it/mag/magazz.htm
I don't know if it is the BL version, call them and ask. It's cheaper than $10.
in Italy you can find the 2sk389 here: http://www.lelettronicaasti.it/mag/magazz.htm
I don't know if it is the BL version, call them and ask. It's cheaper than $10.
Stefanoo said:I don't know if i'm wrong but Nelson told on one of his thread that 2SK370 would be a good replace.
2SK370 may be even more difficult to find than 2SK389. All I know is that two N-channel JFETs 2SK170BL make a good replacement of 2SK389BL in my projects.
The version of the 289 should be necessary "BL" to fit the specification of the project, right?
Hope Nelson will post this thread giving us an advice on an updated component to use for the Aleph One. 🙁
Hope Nelson will post this thread giving us an advice on an updated component to use for the Aleph One. 🙁
Version of 389
The K389 is current source biased, with about 1mA going through each leg. The Idss rating is not so much of an issue.
You can get articles on how JFets work at the Borbely site, and there are some Siliconix application notes that explain, amongst others, biasing schemes for JFets (search the forum). They will answer those questions. Hope this helps.
The K389 is current source biased, with about 1mA going through each leg. The Idss rating is not so much of an issue.
You can get articles on how JFets work at the Borbely site, and there are some Siliconix application notes that explain, amongst others, biasing schemes for JFets (search the forum). They will answer those questions. Hope this helps.
I am perpetually short on sleep, so I don't always think as clearly as I'd like...
...but...
Where on the Aleph 1 schematic do you see a 2SK389? All the versions I'm aware of used IRF MOSFETs. The Toshiba JFETs are not drop in replacement parts.
Grey
...but...
Where on the Aleph 1 schematic do you see a 2SK389? All the versions I'm aware of used IRF MOSFETs. The Toshiba JFETs are not drop in replacement parts.
Grey
short on sleep
Maybe I am short on sleep and Stefano really means aleph 1.
That does not mean though that you are not confused 😀
Maybe I am short on sleep and Stefano really means aleph 1.
That does not mean though that you are not confused 😀
wait a second....i mean Aleph ONE or Alleph 1 that it's the same...ehehe.....to be more specific...i mean the pre phono stage.
Well...on the schematich that i have there are two...or .... 2
2SK389BL .... but if i have the wrong schematich.....
..please email me the correct one at
kyokoforever@virgilio.it
thank 🙂
Well...on the schematich that i have there are two...or .... 2


kyokoforever@virgilio.it
thank 🙂
The phono stage is/was called the Ono, not One. The Aleph 1 was a power amplifier. They're two different animals.
The 2SK389 has been discontinued, as EUVL said above. Some are still available here and there, but they are hard to find. At least here in the US, you're never able to pin people down as to whether they have the GR, BL, or VI versions. You have to buy them blindly, and hope for the best.
As I believe was also said, two 2SK170 JFETs can be hand matched to do pretty much the same job. But again, you run into the GR, BL, VI problem.
Nelson has recently said that he's buying a different part that has similar specs. I don't remember the number offhand, but it's in the front end of the F4. How easy it is to get, I have no idea. I haven't tried. I've pretty much given up on Japanese parts.
Grey
The 2SK389 has been discontinued, as EUVL said above. Some are still available here and there, but they are hard to find. At least here in the US, you're never able to pin people down as to whether they have the GR, BL, or VI versions. You have to buy them blindly, and hope for the best.
As I believe was also said, two 2SK170 JFETs can be hand matched to do pretty much the same job. But again, you run into the GR, BL, VI problem.
Nelson has recently said that he's buying a different part that has similar specs. I don't remember the number offhand, but it's in the front end of the F4. How easy it is to get, I have no idea. I haven't tried. I've pretty much given up on Japanese parts.
Grey
Hi Grey,
in the US there is a place you can find 2sk170Bl for 1$ each: http://www.ampslab.com/components_fets.htm
For the 2sk389, as said before, there is in production the LSK389, that comes in the same Id versions as 2sk389. Linear System is located in the USA.
in the US there is a place you can find 2sk170Bl for 1$ each: http://www.ampslab.com/components_fets.htm
For the 2sk389, as said before, there is in production the LSK389, that comes in the same Id versions as 2sk389. Linear System is located in the USA.
I'm aware of the Linear Systems parts--I was one of, if not the first person to make note of their availability on this site. I don't count them as Japanese, however, being on this side of the Pacific. I have some on hand and find them acceptable, but they do not (yet) have any P-ch complements to the N-ch devices. I have it on good authority that they are working hard towards providing the P-ch parts, but are experiencing delays of one sort or another.
Given that the Ono only requires the '389, Linear Systems is an option for those who want to build the stock circuit. I managed to track down some BL '389s and '109s a while back, so I'm okay for the time being. It took some serious effort to locate them, though.
The thing that people don't seem to acknowledge about some of the sources for Japanese parts is that they frequently list things that they don't have in stock and even if they do happen to have stock, they can't be counted on to have stock next month or the month after. For that matter, a lot of them aren't even in business the following month. I don't have the time, the money, or the patience to chase Japanese parts. It's nearly a full-time job to keep sources lined up, as the roster changes from day to day and week to week.
It makes things difficult in that I've got several things I could post here, but if the parts aren't available to everyone what good would it do? It's a conundrum.
Grey
Given that the Ono only requires the '389, Linear Systems is an option for those who want to build the stock circuit. I managed to track down some BL '389s and '109s a while back, so I'm okay for the time being. It took some serious effort to locate them, though.
The thing that people don't seem to acknowledge about some of the sources for Japanese parts is that they frequently list things that they don't have in stock and even if they do happen to have stock, they can't be counted on to have stock next month or the month after. For that matter, a lot of them aren't even in business the following month. I don't have the time, the money, or the patience to chase Japanese parts. It's nearly a full-time job to keep sources lined up, as the roster changes from day to day and week to week.
It makes things difficult in that I've got several things I could post here, but if the parts aren't available to everyone what good would it do? It's a conundrum.
Grey
Interesting Grey.
Since I am going to use the LSK389 for a Pearl alike phono pre, and since you have experience with both the 2SK and LSK, do you suggest the use of which one, not considering cost and availability, that is only from the technical poit of view?
Since I am going to use the LSK389 for a Pearl alike phono pre, and since you have experience with both the 2SK and LSK, do you suggest the use of which one, not considering cost and availability, that is only from the technical poit of view?
GRollins said:I'm aware of the Linear Systems parts--I was one of, if not the first person to make note of their availability on this site.
Linear Systems has been a regular advertiser in Audio Amateur and AudioXpress since time immemorial.
The LSK389 is about $7+ for a couple pieces. As time=money this is a comparatively small parts investment relative to the sweat-equity in building a pre.
You can still get 2sk170's and match for Idss. A pair is going to come close to the moral equivalent of a 2sk389.
As far as I know, the 2SK170BL and its P-channel complement 2SJ74BL, are still in production. They are being sold at a very modest price. Look up the Market Place and you'll find a lot of members are selling theirs.
Here's a DIYaudio shop with 2sk170bl/2sj74bl's with 0.1mv Idss matched pairs and quads: http://www.amb.org/shop/
-Mal
-Mal
Idss is measured in mA, not mV.Malotron said:Here's a DIYaudio shop with 2sk170bl/2sj74bl's with 0.1mv Idss matched pairs and quads: http://www.amb.org/shop/
-Mal
Read the fine print -- they match FETs which you purchase -- I would hate to purport to measure to some level of microamps and hope to stock inventory of already matched sets.
it's also helpful to know the pinch-off voltage.
Erno Borbely has the 2sk146 dual low noise JFET for sale on his webstore.
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