I've had a year off Hi-Fi. Stuff and Life getting in the way. And I had (maybe still have ?) a problem with my power amp tripping out. And haven't got round to (attempting to) fix it until this week. I have just finished building a balanced stereo high pass filter with a 3db point at 30Hz. Probably not really a first choice activity these days with Parkinsons disease, but whilst its not pretty, I think the joints are good. I bloody hope so. I had to make them all twice, because for the 2nd time of asking I somehow built the thing the wrong f****** way round. I'd checked and checked, and yet somehow still built it arse about face. I have rectified the error. When the missus wakes up I am going to find out if it works. It's going to be tedious if it doesnt...
I am fairly sure it is due to the Quad ESL63's tripping it because their protection circuit is activated . The amp in question is an AHB2 - and it's pretty trigger happy . It reported "over current" on one channel each time. We are pretty sure the problem is that the speakers, which have bugger all output below 50Hz, nonetheless respond to bass frequency signals, and if they are big enough, they move the drivers too far, and the (none-too subtle) protection circuitry triggers.
Previously, using a modified Quad 405-2 power amp, there were no problems. But the Quad 405-2 has a frequency response which amounts to a high pass filter at 20 Hz. The AHB2 is flat to DC. I tried building a high pass filter about a year ago, and yes, you guessed it, built it arse about face first. Honest, I look, and look, and look, and then get called out for a coffee and some bloody gremlin nips in and turns it round. It worked fine in my unbalanced office system, but had a faint hum on one channel in the proper system. I always get this problem when I use an unbalanced connection between the Pip and the AHB2 - although I shouldnt, and whilst one day I'd love to get yer man to figure out why - it seemed easier to just build a balanced version
But somehow, I failed to find the motivation. We have still been using the kit as front right and left channels in our AV set up. It is fine, because its signal comes from a Yamaha AV amp, and we can set it to "small speakers" so bass frequencies are not fed to the PIP/AHB2 but the sub-woofer instead
Solid as a rock like that.
WIsh me luck!
I am fairly sure it is due to the Quad ESL63's tripping it because their protection circuit is activated . The amp in question is an AHB2 - and it's pretty trigger happy . It reported "over current" on one channel each time. We are pretty sure the problem is that the speakers, which have bugger all output below 50Hz, nonetheless respond to bass frequency signals, and if they are big enough, they move the drivers too far, and the (none-too subtle) protection circuitry triggers.
Previously, using a modified Quad 405-2 power amp, there were no problems. But the Quad 405-2 has a frequency response which amounts to a high pass filter at 20 Hz. The AHB2 is flat to DC. I tried building a high pass filter about a year ago, and yes, you guessed it, built it arse about face first. Honest, I look, and look, and look, and then get called out for a coffee and some bloody gremlin nips in and turns it round. It worked fine in my unbalanced office system, but had a faint hum on one channel in the proper system. I always get this problem when I use an unbalanced connection between the Pip and the AHB2 - although I shouldnt, and whilst one day I'd love to get yer man to figure out why - it seemed easier to just build a balanced version
But somehow, I failed to find the motivation. We have still been using the kit as front right and left channels in our AV set up. It is fine, because its signal comes from a Yamaha AV amp, and we can set it to "small speakers" so bass frequencies are not fed to the PIP/AHB2 but the sub-woofer instead
Solid as a rock like that.
WIsh me luck!
