John Curl's Blowtorch preamplifier part II - Page 19

john curl · 3rd July 2009, 06:10 PM

PMA, I don't mind sharing, but I wish that I COULD get in a word or two on this thread. You haven't answered my question PMA, should we have used an aluminum foil plated cigar box, or its equivalent for our case? Are our huge and expensive cases, just a waste of time and money? Also, you are happy with putting ceramic caps in the power supply bypass? Please think, before reacting.

PH104 · 3rd July 2009, 06:13 PM

400 series stainless steels are magnetic and easily machined. They are not as corrosion resistant as the "non-magnetic" 300 series (304, 316) steels.

jan.didden · 3rd July 2009, 06:15 PM

Quote:

Originally posted by jacco vermeulen
Epcos B85321, metallized polyprop foil capacitors.
Manufactured in values up to 4.7uF, and subsequent 6''x2'' sizes.

(= what i use to go through 10mm Alu walls)

Jacco,

Where do you get those - Quakkelstein in Vlaardingen?

Jan Didden

Juergen Knoop · 3rd July 2009, 10:39 PM

Dear John,
as far as I remember, the BT was a transconductance amplifier.
So maybe your answer could be guessed...but I'm curious.

In the case of voltage outputs, two schools of thought exists.
Those of maximising load currents through switches, connectors,wires, traces and solder joints and those which prefers a potentiometric approach.
This may be to a large extend a philosophical issue.
I'm curious about your general design philosophy on this.

Regards

john curl · 3rd July 2009, 10:41 PM

I am not sure what you are talking about, BUT when I use the BEST switches, I don't 'seem' to need DC bias on the passive parts.

john curl · 3rd July 2009, 10:43 PM

Sprague made 10uf feed-through caps in the past, for radio stations, etc. I have seen them.

Juergen Knoop · 3rd July 2009, 10:52 PM

ok, what about line level interface sections, inside or between home stereo equipment, do you prefer low or high load impedances?
Regards

sawreyrw · 3rd July 2009, 11:52 PM

I respect that, but seriously, I can't make any sense out of this thread. What am I missing?

Joshua_G · 4th July 2009, 12:35 AM

Quote:

Originally posted by sawreyrw
I respect that, but seriously, I can't make any sense out of this thread. What am I missing?

May be what's wrong with this thread is some input by some participants …

nicoch58 · 4th July 2009, 12:47 AM

Sorry bear you understain wrong my post ,no Erno....
what I mean is that (all here know ) psu is audio psu as 50% of sound, I learning here that EI or r-core are more "audio" rispect toroid

3rd July 2009, 06:13 PM	#182
PH104 diyAudio Member Join Date: Nov 2001 Location: New Mexico	400 series stainless steels are magnetic and easily machined. They are not as corrosion resistant as the "non-magnetic" 300 series (304, 316) steels. __________________ "When I read about the evils of drinking, I gave up reading." -- Henny Youngman

4th July 2009, 12:47 AM	#190
nicoch58 diyAudio Member Join Date: Oct 2004	Sorry bear you understain wrong my post ,no Erno.... what I mean is that (all here know ) psu is audio psu as 50% of sound, I learning here that EI or r-core are more "audio" rispect toroid __________________ Sic58

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

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 July 2009, 06:10 PM	#181
john curl diyAudio Member Join Date: Jul 2003 Location: berkeley ca	PMA, I don't mind sharing, but I wish that I COULD get in a word or two on this thread. You haven't answered my question PMA, should we have used an aluminum foil plated cigar box, or its equivalent for our case? Are our huge and expensive cases, just a waste of time and money? Also, you are happy with putting ceramic caps in the power supply bypass? Please think, before reacting.

3rd July 2009, 10:39 PM	#184
Juergen Knoop diyAudio Member Join Date: Jan 2007 Blog Entries: 3	Dear John, as far as I remember, the BT was a transconductance amplifier. So maybe your answer could be guessed...but I'm curious. In the case of voltage outputs, two schools of thought exists. Those of maximising load currents through switches, connectors,wires, traces and solder joints and those which prefers a potentiometric approach. This may be to a large extend a philosophical issue. I'm curious about your general design philosophy on this. Regards

3rd July 2009, 10:41 PM	#185
john curl diyAudio Member Join Date: Jul 2003 Location: berkeley ca	I am not sure what you are talking about, BUT when I use the BEST switches, I don't 'seem' to need DC bias on the passive parts.

3rd July 2009, 10:43 PM	#186
john curl diyAudio Member Join Date: Jul 2003 Location: berkeley ca	Sprague made 10uf feed-through caps in the past, for radio stations, etc. I have seen them.

3rd July 2009, 10:52 PM	#187
Juergen Knoop diyAudio Member Join Date: Jan 2007 Blog Entries: 3	ok, what about line level interface sections, inside or between home stereo equipment, do you prefer low or high load impedances? Regards

3rd July 2009, 11:52 PM	#188
sawreyrw diyAudio Member Join Date: Apr 2006 Location: Minnesota	I respect that, but seriously, I can't make any sense out of this thread. What am I missing?