Studio Reference Amplifier

[apexaudio]

Hi Apex. I have not found LF411. I can replace it with TL071 or TL081?
Sorry for my english is bad.

Yes, use TL071 or TL081 offset will be about +/-1mV.

 

[chithanh2507]

Yes, use TL071 or TL081 offset will be about +/-1mV.

Thanks. I'm amateur.

 

[chithanh2507]

Thanks JOHN BALI

 

[shravanth]

apex amplifiers

 

[apexaudio]

apex amplifiers

Nice work,
Regards

 

[Arif Budiyanto]

Greetings...
My SR200 now has dc offset 5mV and 2mV...biased at 7mV at r 0.33 ohm (21mA)...R and C on zobel network are warm tends to hot after more about 15-20 minute that I think start to oscillate.
I use standard SR200 schematic with 20pf capacitor which is soldered on the cooper side of pcb.... I have no scope at moment...
Would you please advice me what the best practice is.... thank you so much...
Best regards
Arif

 

[apexaudio]

Greetings...
My SR200 now has dc offset 5mV and 2mV...biased at 7mV at r 0.33 ohm (21mA)...R and C on zobel network are warm tends to hot after more about 15-20 minute that I think start to oscillate.
I use standard SR200 schematic with 20pf capacitor which is soldered on the cooper side of pcb.... I have no scope at moment...
Would you please advice me what the best practice is.... thank you so much...
Best regards
Arif

You must change or add new compensation, but not without scope.
Regards

 

[DAMANHURI]

I will share schematics of my new amplifiers HD50, HD150 and HD300 with J fets in LTP...

I will wait for your schematic

 

[thimios]

new amplifiers

I will share schematics of my new amplifiers HD50, HD150 and HD300 with J fets in LTP...

Waiting too.

 

[Arif Budiyanto]

You must change or add new compensation, but not without scope.
Regards

I am sorry for asking, just for sure....do you mean bigger compensation caps?
Best Regards,
Arif.

 

[lamir35]

What are the specs? Are there measurements? Are there kits available or how much would it cost to build?

 

[shravanth]

how many turns for 10uH coil at out put of SR200

 

[AndrewT]

10uH is possibly around 30T wound around a AA battery.

 

[shravanth]

10uH is possibly around 30T wound around a AA battery.

thank you andrew

For SR200 what is resister and capacitor value at zobel network

 

[apexaudio]

thank you andrew

For SR200 what is resister and capacitor value at zobel network

go to post #55

 

[shravanth]

go to post #55

thank you sir n what will be the coil n how many turns

 

[thimios]

sr200

What are the specs? Are there measurements? Are there kits available or how much would it cost to build?

Hi dear look here.https://www.youtube.com/watch?v=cuawe2CidbE
Regards.
Thimios

 

[samratsarkar]

Hi Friends,
I have completed the SR200 amp and it is working. But when I am using RCA cables for loud speakers connection then hum noise is noticed if i put my ears close to speakers.

Please advise what need to be done to stop the hum noise.

Regards,
Samrat

 

[mprivitera1]

APEX HV23

Hello apexaudio,

I am going to build an APEX HV23, you have advice for this project?
thanks

http://i56.servimg.com/u/f56/16/58/26/85/2013-111.jpg

 

[apexaudio]

Hello apexaudio,

I am going to build an APEX HV23, you have advice for this project?
thanks

http://i56.servimg.com/u/f56/16/58/26/85/2013-111.jpg

There is thread for more informations about HV23
http://www.diyaudio.com/forums/solid-state/162043-mosfet-amplifier-irfp240-irfp9240-71.html