Studio Reference Amplifier

[drowranger]

CORRECTION ON SR 50 PCB-my deepest apology...

Hope this may help(based on the original schematics of SR50).

ENJOY!!!

Correction made:
1. wrong supply of ic (copper wire of pin 7 should be in 4 and vice versa-see pdf)

2. wrong value of r25 should be 100 not 1k
3. wrong value of r26 should be 100 not 1k
4. wrong value of r27 should be 100 not 3k3
5. wrong value of r28 should be 100 not 3k3

 

[khalsa]

drowranger what are you using pcb design software

 

[drowranger]

drowranger what are you using pcb design software

eagle

 

[khalsa]

Thanks drowranger

 

[sasek]

what voltage power supply can i use for 2 pair power output like macd build?and power supply for 1 pair power output?

 

[overpower]

Hello All!
This is my very first post in this forum
I've been watching for a long time the amplifier topic in this forum, but still haven´t taken my knowledge - my English is also quite bad Anyway I posted a picture in my amplifier experiments of Apex SR200. It has not been tested yet, heatsink must be machined, as well as the electrolytic caps solder for place, then I will test the amplifier.

 

[drowranger]

sr-50

SR50 is Studio Ref Amp for small studio monitors without cascode in VAS.

 

[drowranger]

made mistakes on output transistor


i made correction now

 

[alex mm]

..... another mistake

...... you have another smal mistake , se .......

 

[drowranger]

...... you have another smal mistake , se .......

ok tell me. I will correct it.

 

[alex mm]

.......and so on ....

..... D1 zenner diode must be reversed , R7=1k resistor in wrog position not to pin 4 IC (not this way )..... , output transistors are the same 2SC5200 ? and so on ........

 

[drowranger]

thanks for the correction

..... D1 zenner diode must be reversed , R7=1k resistor in wrog position not to pin 4 IC (not this way )..... , output transistors are the same 2SC5200 ? and so on ........

hope this is fine...

 

[alex mm]

....not OK

....... forget to link , like in pic .

 

[drowranger]

again, again...

....... forget to link , like in pic .

thanks,alex...your the man!

and also change the schematic

 

[drowranger]

scematic

thanks,alex...your the man!

and also change the schematic

 

[AndrewT]

IC1 PIN3 ?
If the unconnected PIN3 floats with PIN2 then the 411 output voltage will always be zerovolts +-output offset +-common mode error.

 

[AndrewT]

It is connected to two diodes. Both are connected to PIN2.
As drawn PIN3 floats with PIN2.

 

[drowranger]

you are right

IC1 PIN3 ?
If the unconnected PIN3 floats with PIN2 then the 411 output voltage will always be zerovolts +-output offset.

 

[drowranger]

hope its ok now...



thanks andrew for checking.

 

[AndrewT]

You have connected PIN3 to Signal Ground.
Label Signal Ground to differentiate it from Power Ground.
Now a question which ground does R21 connect to?

Show the change on the sch.