When I did my initial Straight Talk speakerphone comparison on two CDMA Touch Pro2s, some readers wanted to know how GSM Straight Talk compares to the CDMA version. The result isn’t bad for GSM callers, but CDMA networks provide a richer calling experience when using HTC’s Straight Talk technology on their new speakerphones.

Callers noticed that I sounded better with richer audio fidelity on the CDMA versions from Sprint and Verizon Wireless. On the T-Mobile version, calls sounded like it came from an office speakerphone, noted one caller. Another caller said that it sounds loud, but tinny–meaning hollow–and that there was some crackling noises in the background; the crackling is faint enough where it shouldn’t be a big problem. These GSM calls were all conducted over T-Mobile’s 3G GSM network on a T-Mobile-branded HTC Touch Pro2 in the US.

Aside from the hollow calls and slight crackling, I found that I achieved better call quality when the side microphone is directed towards me, rather than speaking on top of the back of the device by leaning over or on any of the Touch Pro2′s sides away from the microphone. This may help users achieve maximum results in their Straight Talk usage, but may be uncomfortable with more than 1 person hovered around the Touch Pro2 in a mini-conference room like conference call setting.