Honestly, the 'search forum' function is not that difficult.
In less than 30 seconds I found:
Studio Reference Amplifier
Post #4:
amp work on my desk without case on +/-45V DC rail voltage. Sound is without any compromise, and musicans like it.
Post #23:
Power of this amp is enough for small studio monitor speakers, but for large studio monitors power must be increase up to 200W/8R RMS useing 3 pairs of outputs
There are 270 pages of information on that thread, some may be useful, some not. I suggest go to there and try the 'Search This Thread' function on the top right of the page to see if you can locate what you need.
All credit goes to Mr. Miles who create AX20 and Mr. Sonal who design the PCB not to me my
Friend
Regards
Gurpreet Turna
Last edited:
hi is there any sonic difference between A33 and A40 they both looks the same! may be just the output power is different! 😵
AX14P oscillate problem..
Good day Sir Apex...
I just completed my AX14P module. First power up everything seems normal. Short the input, set bias current to 20mA, with 8ohm load. Supply is +-30V. Pics attached..problem is with input short removed...there is a 50Hz signal on the output...as measured on my scope..
pics attached...music is playing but with a hum...please advice as to where the oscillation can originate...
Thanks in advance...
Regards...
Good day Sir Apex...
I just completed my AX14P module. First power up everything seems normal. Short the input, set bias current to 20mA, with 8ohm load. Supply is +-30V. Pics attached..problem is with input short removed...there is a 50Hz signal on the output...as measured on my scope..
pics attached...music is playing but with a hum...please advice as to where the oscillation can originate...
Thanks in advance...
Regards...
Attachments
If you have hum it does not mean that the problem is with your PCB. Hum is not oscillation, it's interference.
Good Day....
I finaly managed to get my AX14P to work. Amp is dead silent now. I had to put a resistor from my signal input to ground. I used a 100R resistor. I am not sure if this is correct or not..but without the resistor the input is very sensitive to any movement which gets amplified thus generating a hum noise on my test speaker....
Please advise or is there still something wrong with my amp..
Regards....
100 Ohm from signal input to ground is too small value,it is a big load for preamplifier. simple 10kOhm potentiometer should do the job,if you have connected everything properly. if you have ground loop somewhere that could be a source of humm.
AX14 requares a separate wire from signal gnd to power supply 0v.
Are you sure that you have this installed?
AX14P noise....
Good Day....
Thanks for the reply...
Yes, signal ground and power 0V is connected. I am sure with 10K pot connected as below the amp will be ok. Will try it now... My question is it normal for this amplifier with the input not connected/open generate a noisy output or must I always connect a 10K pot on the input??? I used this layout...
Thanks in advance...
Good Day....
Thanks for the reply...
Yes, signal ground and power 0V is connected. I am sure with 10K pot connected as below the amp will be ok. Will try it now... My question is it normal for this amplifier with the input not connected/open generate a noisy output or must I always connect a 10K pot on the input??? I used this layout...
Thanks in advance...
Attachments
AX14P noise....
Thanks for the reply...
With input open...amplifier picks up any noise or movement and amplify the signal...very noisy... you can here pop sounds on speaker... I will connect the 10K pot as below... Is this for this amp???
Regards....
Thanks for the reply...
With input open...amplifier picks up any noise or movement and amplify the signal...very noisy... you can here pop sounds on speaker... I will connect the 10K pot as below... Is this for this amp???
Regards....
Attachments
AX14P test wiring setup....
Thanks...noted....will quickly setup and test...
Regards...
Thanks...noted....will quickly setup and test...
Regards...
Good day Thimios...
Amp is working now as advertise.... Thanks a lot for your help... cannot give feedback as to the sound quality as I do not have a test speaker at work... only dummy load.... I'll connect a speaker and some music source tonight and give feedback....
Regards...
macd 🙂🙂🙂
