Bear with me here in this section as it is quite important if you are interested in getting a MH1. Let’s begin by explaining two standards used in making the 3.5mm TRRS plug on headset – OMTP and CTIA (both are organizations for mobile standards). For OMTP, the TRRS plug is wired as [Left-Right-Mic-Ground] (from tip-to-sleeve); for CTIA, the TRRS is wired as [Left-Right-Ground-Mic]. Since OMTP was initially endorsed by Ericsson (and Nokia, which still uses the OMTP standard), all of their cellphone, including those under the Sony Ericsson branding, uses this standard. It also got adopted by a few other cellphone manufacturers as standard before mid 2011, such as LG, Motorola, Sony and Samsung. In mid 2010, the OMTP organization transitioned itself into another organization (the WAC, if you are interest to know), and the OMTP standard for headset was subsequently being phased out by most manufacturers within the following year (* it takes time to sell off old models) in favor of the CTIA standard. Part of the big reason for adapting the CTIA standard might be due to the fact that it is the standard used by Apple on their iDevice, which represent a big share of the headset market. Standardization demands from political groups (i.e. the EU) also played a role to push for one headset standard that will work on both Android and iOS, as well as most dumbphones (except for Nokia, which doesn’t like to play with other for now).
Now that we have learned about the two standards, let talks more specifically in MH1. When MH1 was first announced, it was named ‘LiveSound’ under the Sony Ericsson brand and complied with the old OMTP standard. But when Sony bought out Ericssion’s share of the company and began to introduce their own Sony Xperia brand of Android smarphone, they start to adapt the CTIA standard on all their headsets. The new MH1 (*referred as MH1C, ’C’ is short for ‘CTIA’ presumably) is then renamed as ‘Smart Headset’ to differentiate itself from the old ‘LiveSound’ version. It was supposed to be a fairly easy and clean transition, but unfortunately it isn’t. Some of the new MH1(C) with CTIA wiring is still being sold on various part of the world under the ‘LiveSound’ moniker while other parts of the world already use the new ‘Smart Headset’ moniker. One thing for sure, if you see a MH1 with an old Sony Ericsson logo on the side, it is the OMTP version and not compatible to the newer Android smartphone. If it only has Sony logo stamped on the side, and being referred as ‘smart headset’ or with model name MH1C, then likely it is the new CTIA version. However, the only sure-fire way is to check with the seller for compatibility. In the event that you have acquired the wrong version for your cellphone, don’t despair – an inexpensive TRRS smart adapter will allow OTMP headset to work on a CTIA cellphone (and vice versa).
