Odysseas
Member
Hello everyone,
I have built myself an audio amplifier, based on a project from Randy Slone's 'High-Power Audio Amplifier Construction Manual', added some stuff on my own (a preamp and a headphone-amp, both incorporating an OPA2134 each), but the amp is a bit troublesome. One toroidal transformer with 500VA powers the big amp (2x10.000 uF per rail), a small transformer with 4.8VA powers the preamp and headphone amp. The big amp uses a 2SK1058 and a 2SJ162 per channel.
The headphone-amp gives me decent performance, but the 'big' amp distorts heavily after bass-hits. For about half a second, there just coming loud, ugly noise out of the speakers, more precise, quite deep, low frequency noise. Afterwards the sound seems fine, but the problems re-appeaqrs with almost every bass-hit. Any idea what that might be? It has been suggested, that I am feeding the amp with more input-voltage than it can handle.
There is another problem, which is probably quite trivial: I have some popping in the speakers, sometimes when I turn the amp on, and sometimes when I turn it off. Once there was an electric spark visible, when the relay for the speakers opened, and the speakers popped. Can I treat this with a few ceramic-capacitors across somewhere?
Here are some pictures of the amp, 4 and 5 will probably be the most useful: **broken link removed**
Thanks for any help!!
I have built myself an audio amplifier, based on a project from Randy Slone's 'High-Power Audio Amplifier Construction Manual', added some stuff on my own (a preamp and a headphone-amp, both incorporating an OPA2134 each), but the amp is a bit troublesome. One toroidal transformer with 500VA powers the big amp (2x10.000 uF per rail), a small transformer with 4.8VA powers the preamp and headphone amp. The big amp uses a 2SK1058 and a 2SJ162 per channel.
The headphone-amp gives me decent performance, but the 'big' amp distorts heavily after bass-hits. For about half a second, there just coming loud, ugly noise out of the speakers, more precise, quite deep, low frequency noise. Afterwards the sound seems fine, but the problems re-appeaqrs with almost every bass-hit. Any idea what that might be? It has been suggested, that I am feeding the amp with more input-voltage than it can handle.
There is another problem, which is probably quite trivial: I have some popping in the speakers, sometimes when I turn the amp on, and sometimes when I turn it off. Once there was an electric spark visible, when the relay for the speakers opened, and the speakers popped. Can I treat this with a few ceramic-capacitors across somewhere?
Here are some pictures of the amp, 4 and 5 will probably be the most useful: **broken link removed**
Thanks for any help!!