Trendsetter sent around a link to the PDF of Bob's application note on the new LSK489:
http://www.trendsetter.com/v/vspfiles/assets/news/LSK489 Application.pdf
http://www.trendsetter.com/v/vspfiles/assets/news/LSK489 Application.pdf
Seems to be very promising. Did you try it? ...The LSK170 has an input C of around 20 pF and g'old 2SK170BL around 30 pF. If low input C reduces the IMD this thing must "sound" quite good.
Difficult to source here in Germany.
Btw. there also exists a LSK589 - didn't read the specs yet.
Datasheet on the LSK589 is out -- Ciss 5pF, noise 4nV/RtHz, gm 4-10mS
There is a J-channel complement to the 489 -- LSJ489
I have used the LSK389 in Dennis Colin's LN Amplifier.
They also released lsj689 Linear Systems || ULTRA LOW NOISE P-CHANNEL DUAL JFET last year. The LSK589 seams to be even more promising then LSK489 even if Ciss is a little bit higher. As far as I know LSK489 was criticized because of the lower transconductance (compared to LSK389 (LSK170) or 2sk170) but know LSK589 seems to solve this issue. But I couldn't find a graph in the datasheet about operation linearity.
Hi,
did you try this address
IBF Ingenieur-Büro-Fluck
He is the offical distributor and i got my SST404 from LIS very fast there-
BR
Gunni
I can't see either LSK489, or LSK589, or LSK689 listed in USA or Germany stock. Nor the LSJ of those numbers.
Hi,
Think, they don't have a minimum order limit, because i got an offer, that said <99 pcs, i.e 1 to 99 pcs. Hope you won't order 1 or 2 pcs. I made an request for 5 pcs, and ordered 8 of the SST404 for Suzyj AEM6000.
No problem
@ AndrewT, it was only the advise, that Ingenieur-Buero-Fluck is the official German Distributor für Linear Integrated Systems parts, and so you dont need to order in the states, and pay high costs for Express delivery and import taxes. Check the prices for delivery to Scotland (shipment about 35$ + taxes)
Cheers with a Canadian Club
Gunni
> LSK589 seems to solve this issue
2SK170 has 30mS and 1nV/sqrtHz.
LSK589 has 4nV/sqrtHz and 4-10mS.
2SK209 has 15mS and 1.2nV/sqrtHz, is active product, and costs much less.
Just needs a bit of matching, but then you have it in your own hands as to how well the match is.
The LS dual fets have relatively poor match at 10% Idss.
Toshiba duals were 3%.
If you hand match 2SK209 yourself, you can match to ~10µA.
Standard stock at Mouser, DK, etc.
Patrick
2SK170 has 30mS and 1nV/sqrtHz.
LSK589 has 4nV/sqrtHz and 4-10mS.
2SK209 has 15mS and 1.2nV/sqrtHz, is active product, and costs much less.
Just needs a bit of matching, but then you have it in your own hands as to how well the match is.
The LS dual fets have relatively poor match at 10% Idss.
Toshiba duals were 3%.
If you hand match 2SK209 yourself, you can match to ~10µA.
Standard stock at Mouser, DK, etc.
Patrick
@Gunni - Thx for your info.
@Patrick you'r right - I meant in comparison to the LSK489. SK170 are more gaining. Im searching Duals because I hate matching by hand ... need to find a way to do it faster. But 2SK209 looks pretty good and it is a more modern part. Do you have any other suggestion for modern jfets? BF862 seems to be good aswell.
@Patrick you'r right - I meant in comparison to the LSK489. SK170 are more gaining. Im searching Duals because I hate matching by hand ... need to find a way to do it faster. But 2SK209 looks pretty good and it is a more modern part. Do you have any other suggestion for modern jfets? BF862 seems to be good aswell.
The LSK489 Application Note
written by Bob Cordell is surely nice reading.
He provides several very interesting circuits on how to use JFET.
He even shows a complete power amplifier circuit. Towards the end.
http://www.cordellaudio.com/JFETs/LSK489appnote.pdf
written by Bob Cordell is surely nice reading.
He provides several very interesting circuits on how to use JFET.
He even shows a complete power amplifier circuit. Towards the end.
http://www.cordellaudio.com/JFETs/LSK489appnote.pdf
Nice!
Cordell is very good when it comes to minimize noise. Like in Phono amplifiers.
He often use JFET for this.
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