krisjan
100+ Head-Fier
- Joined
- Sep 27, 2008
- Posts
- 138
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- 11
oh and i just want to thank this tangentsoft guy for his wonderful site and information sharing - it's really great to get all this info and step-by-step help for free! cheers!
would higher impedance phones have less hiss at higher source volumes? |
Originally Posted by millwood /img/forum/go_quote.gif hiss is almost a universal sign of opamp oscillating and you shouldn't have it at all if the amp is working properly. that aside, a higher impedance phone means less attenuation by R5, everything else being equal, that and means louder sound on the headphone. but phone sensitivity typically goes up for higher impedance phones so that's hard to say. |
Originally Posted by krisjan /img/forum/go_quote.gif well i've been looking at Basic Troubleshooting for Headphone Amplifiers and i'm quite sure my problem is listed as Quiet hiss in the headphones...as i said the bsg cmoy also has it... |
Originally Posted by krisjan /img/forum/go_quote.gif well i've been looking at Basic Troubleshooting for Headphone Amplifiers and i'm quite sure my problem is listed as Quiet hiss in the headphones...as i said the bsg cmoy also has it... |
ideally, you don't want the amp's input impedance (=R2//opamp's input impedance =~R2 since opamp's input impedance is much larger than R2) to overwhelm the pot - but even if that happens it is not the end of the world. |
Originally Posted by nsx_23 /img/forum/go_quote.gif Does anyone here detect major differences between running a CMOY of 1 9V VS 9V batteries? The reason I'm asking is that with my previous 2 builds, I couldn't get 2 9V batteries to fit in the altoids tins at all, and am wondering if there are any major negative effects. I completed another build last night which uses 2 9V, and am now comparing it to the single 9V builds. The dual 9V seems to have slightly better bass so far, but more testing is needed. And lol at the oversized caps above! I used 470uf caps and thought they were big enough... |