B1 Preamp - Help Me!

Professor smith · 3rd September 2008, 05:33 PM

I am having alot of trouble getting the transistors and capacitors at the moment. I will have to get them online. Can someone please tell me where I can buy these matched Jfets?

Also where do I get the 18V power supplY?
Thanks

Salas · 3rd September 2008, 05:40 PM

Ebay is your mate.

As for the pot before or after the unity gain circuit, that depends on where you have the weakest situation. 90% of cases is the driving of the interconnects and main amp's input impedance without loss of signal or response deviations.

Nelson Pass · 3rd September 2008, 06:19 PM

http://www.linearsystems.com/distrib...rnational.html

They do not have to be matched, but it is preferred that they are.

jacco vermeulen · 3rd September 2008, 06:32 PM

Quote:

Originally posted by Professor smith
a lot of trouble getting the transistors

Eeer, Gov.
As you've got your knickers in London, why not just pop over to Grandata in Wembley for the K170 ?

Professor smith · 3rd September 2008, 06:38 PM

Quote:

Originally posted by jacco vermeulen

Eeer, Gov.
As you've got your knickers in London, why not just pop over to Grandata in Wembley for the K170 ?

I sure will. That is within walking distance.

But the trouble is, will they match them for me?

jacco vermeulen · 3rd September 2008, 06:42 PM

At 50P each you could ask them for a couple of the same batch run and match them in situ.
Which is what Big Daddy P sometimes does, so he says.

Goodlooking motor and nice birds on your homepage, Prof.

Professor smith · 3rd September 2008, 06:47 PM

regarding the capacitors,( not the electrolytics), but the metalised polypropylene, what other types can I use and wat values can they be between for the 1Uf and the 10Uf?

Professor smith · 3rd September 2008, 06:50 PM

This is turning out to not be as asimple as I thought. I dont know how to match them, I j ust wanted to buy them and solder them. What can I do?

Salas · 3rd September 2008, 07:00 PM

You introduce me to Daphne, I give you 4 matched 2SK170s for free.

jacco vermeulen · 3rd September 2008, 07:00 PM

Buy a DMM.

You can pretty much use any cap you fancy, just not the same as a polyprop.
If you're not in a hurry and /or can shortly get by with a crappy, i'm about to order some NOS Wima MKP for 24p per uF, could send you some.

3rd September 2008, 06:42 PM	#6
jacco vermeulen diyAudio Member Join Date: Oct 2004 Location: At the sea front, Rotterdam or Curaçao	At 50P each you could ask them for a couple of the same batch run and match them in situ. Which is what Big Daddy P sometimes does, so he says. Goodlooking motor and nice birds on your homepage, Prof. __________________ Not so much,.......if it says "ZM" in the corner.

3rd September 2008, 07:00 PM	#10
jacco vermeulen diyAudio Member Join Date: Oct 2004 Location: At the sea front, Rotterdam or Curaçao	Buy a DMM. You can pretty much use any cap you fancy, just not the same as a polyprop. If you're not in a hurry and /or can shortly get by with a crappy, i'm about to order some NOS Wima MKP for 24p per uF, could send you some. __________________ Not so much,.......if it says "ZM" in the corner.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Tube Preamp Popping on Source Input Change (?) / 6DJ8 Preamp On Chip Amps	MartyM	Tubes / Valves	3	16th October 2008 04:52 AM
Guitar Preamp = MIC Preamp = other preamp ,,are they all same?	Paswa	Solid State	1	12th March 2008 05:16 PM
twisted pear Preamp/other suggestions for Preamp kit	LukeDuke	Chip Amps	1	1st February 2008 09:57 PM
Electret mic preamp - will phono preamp work?	darthmullet	Analogue Source	6	12th October 2007 07:32 AM
wiring preamp outs on a preamp	bonsai171	Solid State	4	22nd March 2004 10:13 PM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

3rd September 2008, 05:33 PM	#1
Professor smith Banned Join Date: Sep 2008	I am having alot of trouble getting the transistors and capacitors at the moment. I will have to get them online. Can someone please tell me where I can buy these matched Jfets? Also where do I get the 18V power supplY? Thanks

3rd September 2008, 05:40 PM	#2
Salas diyAudio Chief Moderator Join Date: Oct 2002 Location: Athens-Greece	Ebay is your mate. As for the pot before or after the unity gain circuit, that depends on where you have the weakest situation. 90% of cases is the driving of the interconnects and main amp's input impedance without loss of signal or response deviations.

3rd September 2008, 06:19 PM	#3
Nelson Pass The one and only Join Date: Mar 2001	http://www.linearsystems.com/distrib...rnational.html They do not have to be matched, but it is preferred that they are.

3rd September 2008, 06:47 PM	#7
Professor smith Banned Join Date: Sep 2008	regarding the capacitors,( not the electrolytics), but the metalised polypropylene, what other types can I use and wat values can they be between for the 1Uf and the 10Uf?

3rd September 2008, 06:50 PM	#8
Professor smith Banned Join Date: Sep 2008	This is turning out to not be as asimple as I thought. I dont know how to match them, I j ust wanted to buy them and solder them. What can I do?