Sweet on replacing those crappy old 4558s lol. I've considered that myself. Nice to see a report of someone that has actually done it. I should have documented the values I settled on but I never exactly what I would call perfected either radio of mine. I had full intentions of coming back to them and doing a full map out and perfecting of all the mods but a guy liked the one I was running rack on so much he talked me out of it like it was and the one in my mobile was so good I just left it in there too lol. I'm still running it! Maybe I'll revisit it someday but it's great just the way I left it. I run it every day! I'm glad someone has gotten some use from my posts. Check me out on my Facebook...Panic Attack.Thank you so much for responding to these posts. I might try your suggestion with the different capacitors for the receive end of the Q6. I just reverted it back to the stock receive when I was swapping different caps out. That's awesome that you run rack gear also. I just find that way much more versatile because it will work for any radio you wire it up for and you will always get unsolicited compliments on your audio. I also replaced the two op amps from the 4558s to 4580s. It made a big difference in the high end silibance that was just muddy to okay before. More clean and crisp. Even with the stock microphone like you said sounds so good comparatively after the mods. The 575 is a great mic to hold on to. For studio mics I have been using the Heil PR40. Other microphones work great too but the flat response of the PR40 just makes the wideness of the audio stand out where the other studio mics don't do that. Thanks for your input, without your help I wouldn't have been able to do this!
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