Update bootloader? HD Voice?

[ED2O9]

I'm hoping that someone can point me in the right direction. I gave my wife my Evo 4G LTE over a year ago, and it's worked great running Mean Bean (not sure about the version). The phone is unlocked, rooted and S-Off. Recently, I thought it would be a good idea to update it to KitKat, mainly because I was hoping that the newer ROMs would utilize HD voice. Long story short, I realized that I need to have the 2.10.0000 bootloader and mine is 1.19.something. So, I have a couple questions:
1. Do the newer custom ROMs support HD voice, or do I need to revert to stock?
2. What is the recommended method to update the bootloader?

Sorry if I seem clueless, but I've moved on from this phone a while ago and forgot all about the S-On/S-Off hoops you have to jump through.

 

[Magnum_Enforcer]

I'm hoping that someone can point me in the right direction. I gave my wife my Evo 4G LTE over a year ago, and it's worked great running Mean Bean (not sure about the version). The phone is unlocked, rooted and S-Off. Recently, I thought it would be a good idea to update it to KitKat, mainly because I was hoping that the newer ROMs would utilize HD voice. Long story short, I realized that I need to have the 2.10.0000 bootloader and mine is 1.19.something. So, I have a couple questions:
1. Do the newer custom ROMs support HD voice, or do I need to revert to stock?
2. What is the recommended method to update the bootloader?

Sorry if I seem clueless, but I've moved on from this phone a while ago and forgot all about the S-On/S-Off hoops you have to jump through.

The latest official update was to Android 4.3 which is Jelly Bean, not KK. I believe the HD voice update was part of the software version 3.17 update (Hboot 2.09). There were only 2 or 3 custom ROM's for that particular software version, mostly due to the fact that it was not a major update for the EVO LTE. Any ROM based off that software version should support HD voice. You can run the RUU for that update and you'll remain S-off. Hit the top link in my sig and scroll down to the section on RUU's for further info. This method will also update you to Hboot 2.09.

 

[chemao]

The latest official update was to Android 4.3 which is Jelly Bean, not KK. I believe the HD voice update was part of the software version 3.17 update (Hboot 2.09). There were only 2 or 3 custom ROM's for that particular software version, mostly due to the fact that it was not a major update for the EVO LTE. Any ROM based off that software version should support HD voice. You can run the RUU for that update and you'll remain S-off. Hit the top link in my sig and scroll down to the section on RUU's for further info. This method will also update you to Hboot 2.09.

This doesn't answer the question of how to get to HBOOT 2.10.