Some other Source Follower COnfigurations

[EUVL]

> I would be quite keen to make the DAO with Taylor mod, where can you get the parts for this amp? I Can I use a j74 instead of J103 or is it too much voltage?

No you cannot, because you need a P-JFET with a low transconductance. If you talk to Steen nicely, maybe he can help with 2SJ103s.

> Does anyone sell loveltech fets and the constant current diodes?

http://www.diyaudio.com/forums/showt...52#post1646552

Just in time. Lucky you.

Failing that :
http://www.audioprojekte.de/html/semiconductors.html

Get them while you can. They are amazing devices, if you use them right.


Patrick

[Luke]

Hi Patrick,

thanks for the link, I missed that one. I also found this:

For sale : Constant Current Diode 1N5314, 100V, 4.7mA

Ordered a couple of those too.


Thanks for sharing it with us.

[EUVL]

This guy claims to have 12000 pieces and are offering US$2.75 for matched :

http://www.diyaudio.com/forums/showt...70#post1646970

12,000 will last the DIY needs for decades. There is no more reason not to build the DAO TCS, or even the DAO TCS-X.




Patrick

[jameshillj]

Patrick,
He hasn't actually got any of the 12,000 yet and he's been "Doing the Deal" for quite a while now and you know the saying about things "inthe mail"! - sorry Dave.

Seriously, I wouldn't imagine they're quality control rejects or production-end discards - a quick random test will tell all.

Good price for matched - tolerance is ..?

[steenoe]

Originally posted by EUVL
>

No you cannot, because you need a P-JFET with a low transconductance. If you talk to Steen nicely, maybe he can help with 2SJ103s.


Patrick

Luke;
No problemo at all But a little warning is appropriate! I ordered 30 pcs at first and barely managed to get 2 matched pairs. I was probably just unlucky, 'cause usually the Toshiba's just keep rolling up matching devices. Matching/measuring my stock of 389/109's spawned several quads within 1% Man, did they match!
Well, I can get a few hundred of those 2SJ103's, in case you want some. Just shoot me a mail.

[Luke]

This guy claims to have 12000 pieces and are offering US$2.75 for matched :

Heavy user

Well, I can get a few hundred of those 2SJ103's, in case you want some. Just shoot me a mail.

another heavy user

Thanks for the kind offer Steen, Ill mail you.

[twitchie]

Is there any other alternative to the J511? I've read some other threads saying that you can use another 25V jfet with gate and source tied together with a resistor in front of it, but I have no idea what jfet and resistor value to use

Would anyone please be able to help with a modified version without the J511?

[h_a]

what jfet and resistor value to use

Yes that depends on the IDSS of the jfet; alternatively you can use a pot or more failsafe, a pot with a resistor in series.

Have fun, Hannes

[dviswa]

Steenoe,

YGPM.

Dinesh

[fff0]

Originally Posted by EUVL

Someone asked about modifications to the DAO follower as built by Steen.

This is the version with the Taylor Current Source.
The 2SJ103 should have about 8mA Idss.

Depending on JFET Vgs variations, the resistor values might need adjusting. I should start with a 1k trimpot for R1 to set DC offset to zero first.

Hope you'll build this. Total dissipation about 15W.


Patrick

Hi hi

Can anybody let me know if:
1) Is this the last alteration of this circuit?
2) A headamp? If so, around 1w output?