pics of the testing.
no hiccup during testing, no blown fuses, although some sparks occur in the PSU board due to loose contact in one of the capacitor pin, overall it is success. after confirmation that output DC offsets read 10mV, I connected the speaker and fed some music on the input signal.
my impression, the sound is pleasing, crisp and clear, better than my commercial amplifier in terms of sound quality.
i'm using 45-0-45Vac transformer temporarily from my existing commercial amp.
off to make additional channel for stereo mode.
many thanks apex for the good design of this amplifier!
no hiccup during testing, no blown fuses, although some sparks occur in the PSU board due to loose contact in one of the capacitor pin, overall it is success. after confirmation that output DC offsets read 10mV, I connected the speaker and fed some music on the input signal.
my impression, the sound is pleasing, crisp and clear, better than my commercial amplifier in terms of sound quality.
i'm using 45-0-45Vac transformer temporarily from my existing commercial amp.
off to make additional channel for stereo mode.
many thanks apex for the good design of this amplifier!
Attachments
pics of the testing.
no hiccup during testing, no blown fuses, although some sparks occur in the PSU board due to loose contact in one of the capacitor pin, overall it is success. after confirmation that output DC offsets read 10mV, I connected the speaker and fed some music on the input signal.
my impression, the sound is pleasing, crisp and clear, better than my commercial amplifier in terms of sound quality.
i'm using 45-0-45Vac transformer temporarily from my existing commercial amp.
off to make additional channel for stereo mode.
many thanks apex for the good design of this amplifier!
Thank you for building B500, enjoy in good sound.
Regards
b 500
but I have a problem. plz tell me a suitable way to increase the gain. plz try to help me on this occasion to solve my problem .can you tell me how to bridge this amp.
apex sir i made this b500.it has a quality sound..i was wondered by hearing this sound..
but I have a problem. plz tell me a suitable way to increase the gain. plz try to help me on this occasion to solve my problem .can you tell me how to bridge this amp.
Hi Apex and friends!
I have 2 channels of B500 connected to only one PSU. My torroidal transformer is giving output of 2x55vac to rectifier giving an output +/-80vdc rail voltage.
All grounds (input, output and speakers) of 2x B500 are connected to the PSU ground. Signal input of one B500 is connected to left signal source while the other is connected to right signal source. Although the 2x B500 is working, however the sound is not so clean because some noise or hum is present. How do I correct this problem?
Note: If I remove one of the B500, the other one performs a clean sound. No hum is present.
I have 2 channels of B500 connected to only one PSU. My torroidal transformer is giving output of 2x55vac to rectifier giving an output +/-80vdc rail voltage.
All grounds (input, output and speakers) of 2x B500 are connected to the PSU ground. Signal input of one B500 is connected to left signal source while the other is connected to right signal source. Although the 2x B500 is working, however the sound is not so clean because some noise or hum is present. How do I correct this problem?
Note: If I remove one of the B500, the other one performs a clean sound. No hum is present.
a picture of your set-up helps...make sure your speaker ground return leads go direct to psu 0volt point abd not thru any pcb gound...
sir i very much interested in making this amp looking at its apparent simple design can u plz forward the construction details my email address robinsrakath at gmail dot com ........... if u have any pics of the amp it would be very helpfull and how r the sonics??. can i use any other op amp ic in the place of NE5532, (ie like TL072)
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Attached illustrates how I set the ground wirings.
Attachments
Try to disconnect the one without noise and see if the noise still exist on the suspected one, if the noise disappear while anyone of them is disconnected then there must be grounding issue somewhere.....
regards,
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There's your mistake.
Never use the PSU Zero Volts as the Main Audio Ground (MAG).
Build a separate MAG with it's location optimised for good audio signal processing.
Bring a wire from the PSU Zero Volts to the MAG.
do not allow your signal ground share the same wire as your speaker ground wire, run them separate going to the 0 voltage(ground) point...
Please enlighten me, what is the technical difference of using separate wires down to the PSU ground against bringing one single wire from PSU ground to a common single connection point where all ground wires meet?
The charging current pulses in the transformer secondary circuit MUST NOT be allowed to contaminate any other signal return connection.
The easiset way to avoid that is to take a single wire from the PSU zero volts to the MAG.
The MAG MUST be located for best audio performance. That location is usually not at the PSU.
The easiset way to avoid that is to take a single wire from the PSU zero volts to the MAG.
The MAG MUST be located for best audio performance. That location is usually not at the PSU.