Heil GM-5
Well,we could be here typing lot of words to explain what is going on today with some Heil mics but I am going to be the most simple possible for all of you to understand why its been said that this mic might sound "moody" in some radios.
If you see the "specs" of this good mic,it says it respond from 50 to 18,000 Hz.The majority of radios today on the market that TX on SSB will have a narrow audio spectrum that goes from 300 to 2700Hz because of its builtin 2.4 Khz SSB filter.This means that even the GM-5 have a low end reaching 50Hz on those radios 250 Hz of its range will be lost and also there won't be any chance to produce a moody audio because of the cut around 300Hz,also the radio will sound with just good "comunications quality" but not with wide audio,for me that is a waste of money for using a good mic on a standard radio when a cheap mic for less than 50 bucks will sound the same.
Now what happens with modern radios like the FT-950,FT-2000,TS-2000,TS-870,TS-590 (the newer),IC-756Pro series,IC-746Pro,etc ? Well all of those radios are capable to respond on TX as low as 40 Hz some of them meaning the full range of the GM-5 will pass trough the mic preamp and DSP BUT be carefull because there are some "dangerous" audio freqs around 200Hz that if not well equalized will produce easily the mentioned moodiness,so that is why on those modern radios If you don't know how to EQ properly the GM-5 you definitively will sound moody.Fortunately all those radios specially the FT-950 and FT-2000 has a very well designed 3 bands parametric EQ that will allow you to produce an excellent wide well balanced audio from 50 or 60Hz all the way up to 3000Hz with a nice and sweet modulation using this GM-5,In the case of Kenwood radios the company has preset some different EQ like BB1,BB2,HB1,HB1 and its up to you to test wich fit better with your voice to avoy the moody sound or another alternative is to use the free sofwares available at Kenwood website to equalize youself the TX audio using your PC/laptop.
With Icom radios the job is done easy trough the "bass" and "treble" settings of the menu.
Hope this clear the doubt about moody sound with the GM-5.
Thanks for reading.
Hector
AD4C
Lake Worth,FL