SOAP MKIII (Simple OpAmp Pre) With onboard PSU - Page 20

zei · 29th April 2009, 06:37 AM

Those look great Stream !

The input caps look awesome

Now, I planned to redo the layout abit to make it a tad even simpler. However i have,nt had the time for it realy and i,m actualy thinking of just leaving it as it is. It is already simple..

So i,m proberly going to order a bunch of boards again. (and keep one of them this time

)

Drop me an email if there is any interrest..

/JZ

Stream · 9th May 2009, 06:49 PM

One more photo.

It's almost ready. Just need to add connectors and mosfets on headamp.

P.s. that photos, which I have posted before has one mistake , stupid mistake

I placed 2*lm317 instead of 317+337

When I was testing SOAP, I was embarrased, why negative rail has +20V instead of -10.5V

mikesnowdon · 9th May 2009, 08:00 PM

What are you building there Stream? Lovely PCB's you making there

billyk · 12th June 2009, 11:42 PM

Any movement on this? I would love a board! Seems like just the ticket for my system. Thanks.

gabanyayaya · 16th June 2009, 01:46 PM

hi everybody,

i got 2 questions regarding the SOAP preamp. hope somebody can give some comments

1. Is ok to use a choke with the SOAP before transformer since i have spare unused.

2. I need to know what type of fuse should i use with this preamp before transformer if i feed it with 230VAC?

Thanks

troystg · 16th June 2009, 01:57 PM

Quote:

Originally posted by gabanyayaya
hi everybody,

i got 2 questions regarding the SOAP preamp. hope somebody can give some comments

1. Is ok to use a choke with the SOAP before transformer since i have spare unused.

2. I need to know what type of fuse should i use with this preamp before transformer if i feed it with 230VAC?

Thanks

Are you sure you don't mean choke AFTER the transformer?

As in a CLC supply?

Never heard of a choke on the AC side.. I guess it is possible...

mikesnowdon · 16th June 2009, 03:06 PM

Quote:

Are you sure you don't mean choke AFTER the transformer? As in a CLC supply? Never heard of a choke on the AC side.. I guess it is possible...

Indeed it is.

See here:

Searching for Clean Powerr.

AndrewT · 16th June 2009, 04:34 PM

That's not a choke (=inductor) before the transformer.
That is simply a transformer driving a second or third transformer.

Nothing unusual about that the power supply companies do that all the time.

Now back to Gab's enquiry.

mikesnowdon · 17th June 2009, 01:38 AM

Quote:

Now back to Gab's enquiry.

Well your the man, man. So what about Gab's enquiry?

Im not worthy........

gabanyayaya · 17th June 2009, 03:12 PM

The coke (inductor....or what ever it is) was given by a friend who previously use it in his diy amp. Put it before the tranny and it works.

No value but he said up to 150VA....

Need to know is it worthwhile doing this for the SOAP and if yes why it's not popular among solid state builders....

And what's the fuse option for a tranny used i like mention before?

29th April 2009, 06:37 AM	#191
zei diyAudio Member Join Date: Feb 2005 Location: Gothenburg, Sweden	Those look great Stream ! The input caps look awesome Now, I planned to redo the layout abit to make it a tad even simpler. However i have,nt had the time for it realy and i,m actualy thinking of just leaving it as it is. It is already simple.. So i,m proberly going to order a bunch of boards again. (and keep one of them this time ) Drop me an email if there is any interrest.. /JZ __________________ Tala är tiga, silver är guld

9th May 2009, 08:00 PM	#193
mikesnowdon diyAudio Member Join Date: Aug 2007	What are you building there Stream? Lovely PCB's you making there __________________ www.drugfreeworld.org

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9th May 2009, 06:49 PM	#192
Stream diyAudio Member Join Date: Aug 2008	One more photo. It's almost ready. Just need to add connectors and mosfets on headamp. P.s. that photos, which I have posted before has one mistake , stupid mistake I placed 2*lm317 instead of 317+337 When I was testing SOAP, I was embarrased, why negative rail has +20V instead of -10.5V

12th June 2009, 11:42 PM	#194
billyk diyAudio Member Join Date: Oct 2005 Location: North Central Mass, USA	Any movement on this? I would love a board! Seems like just the ticket for my system. Thanks.

16th June 2009, 01:46 PM	#195
gabanyayaya diyAudio Member Join Date: Aug 2008	hi everybody, i got 2 questions regarding the SOAP preamp. hope somebody can give some comments 1. Is ok to use a choke with the SOAP before transformer since i have spare unused. 2. I need to know what type of fuse should i use with this preamp before transformer if i feed it with 230VAC? Thanks

16th June 2009, 04:34 PM	#198
AndrewT diyAudio Member Join Date: Jul 2004 Location: Scottish Borders	That's not a choke (=inductor) before the transformer. That is simply a transformer driving a second or third transformer. Nothing unusual about that the power supply companies do that all the time. Now back to Gab's enquiry.

17th June 2009, 03:12 PM	#200
gabanyayaya diyAudio Member Join Date: Aug 2008	The coke (inductor....or what ever it is) was given by a friend who previously use it in his diy amp. Put it before the tranny and it works. No value but he said up to 150VA.... Need to know is it worthwhile doing this for the SOAP and if yes why it's not popular among solid state builders.... And what's the fuse option for a tranny used i like mention before?