Studio Reference Amplifier

Hello Friends...,
I am half done with my SR 200 project.. Presently I am stuck with the power supply design.. I am considering 40000uf/100v storage capacitors per rail total 80000UF/100V...

Let me know if this is ok or I need to increase the storage.

I am using 1.2 KVA , 55 VAC Transformer.

Regards,
Samrat


For another time thanks Mr. Apex :)
first sr200 and then ax11;)
four amplifiers in one month......good score.
 
Nice transformer,
I guess you will be running a stereo pair of amps from same supply,

I run my amp max 100-150W per channel.
I'm running my stereo SR200's from 45VAC toroidal with 40000uF per rail and I have good results.

Wish I had a transformer like yours tho, should keep those caps pumped up :D
 
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sr200 studio refer.

SR 200 first steps:lickface::lickface::lickface:
 

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sr200 studio refer.

SR 200 first steps:lickface::lickface::lickface:

Sr200 last steps!!!!!
Mr Apex ....idle current sr200 1) +/-35v with 2 pairs output? 2) +/-45v 2 pairs? 3) +/-55v 2 pairs? At this time i have 2x2sc3264 ,2x2sa1295.
Max rail voltage?
Thanks.
excelent sound!!!!!!!
Mr Apex subclinical.
Photos from first test ....tomorrow .
Soon on youtube:)
 
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Sr200 last steps!!!!!
Mr Apex ....idle current sr200 1) +/-35v with 2 pairs output? 2) +/-45v 2 pairs? 3) +/-55v 2 pairs? At this time i have 2x2sc3264 ,2x2sa1295.
Max rail voltage?
Thanks.
excelent sound!!!!!!!
Mr Apex subclinical.
Photos from first test ....tomorrow .
Soon on youtube:)
Today ι tried the amplifier sr 200 studio ref.
Sound is Apex! but on osciloscope news aren't so good because of oscilation in square pulse as shown on attachement photo.
Mr apex help please:)
Do you think that is a ground loop?
What can i do?
My psb is from Alex mm in post #259
Thanks.
Regards.
 

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....on osciloscope news aren't so good because of oscilation in square pulse as shown on attachement photo.....

That looks like overshoot and not oscillation. There would be a peak in the HF response . Somewhere much above the audio band. How bad does it get with a 1uF or 2 uF in parallel with an 8 ohm load ? Keep the amplitude low !

I don't see a L/R on the output stage. Small inductor coil with a resistor in parallel with it. Might tame this response.
 
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That looks like overshoot and not oscillation. There would be a peak in the HF response . Somewhere much above the audio band. How bad does it get with a 1uF or 2 uF in parallel with an 8 ohm load ? Keep the amplitude low !

I don't see a L/R on the output stage. Small inductor coil with a resistor in parallel with it. Might tame this response.

Thanks for replay.
I'm afraid that is oscillation.Increasing volume and extented time/div shown clear
this.
For the momment i have not zobel filter.
1uf or 2 parallel with an 8r load?
I'm sorry but this test burn my hexfet amplifier some days ago......
Do not intend to do it again SOON:eek:
 
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Today ι tried the amplifier sr 200 studio ref.
Sound is Apex! but on osciloscope news aren't so good because of oscilation in square pulse as shown on attachement photo.
Mr apex help please:)
Do you think that is a ground loop?
What can i do?
My psb is from Alex mm in post #259
Thanks.
Regards.

Replace R18 with 2k2 instead 1k, I have no expirience with this pcb but you must add zobel network.
Regards
 
sr200 studio refer.

Replace R18 with 2k2 instead 1k, I have no expirience with this pcb but you must add zobel network.
Regards
Hi Mr Apex.
I have made a zobel just with i had this time and test again.
first picture is for +/-35v rail 50mv on 0.33r idle current .
out.14vRMS/8R at 11Khz.Please take a look.
Second picture is under same conditions
+/-35v
1 pair 2sc5200/1943
50mv on 0.33
450mv inp./1khz just before start symetrical cliping
19vRMS out/8r
and the draft zobel
 

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Hi Mr Apex.
I have made a zobel just with i had this time and test again.
first picture is for +/-35v rail 50mv on 0.33r idle current .
out.14vRMS/8R at 11Khz.Please take a look.
Second picture is under same conditions
+/-35v
1 pair 2sc5200/1943
50mv on 0.33
450mv inp./1khz just before start symetrical cliping
19vRMS out/8r
and the draft zobel

Speaker terminal from post #55, #43 include DC protect with triac and zobel network
http://www.diyaudio.com/forums/solid-state/173462-studio-reference-amplifier-6.html
Do you replace R18 with 2k2?