The GB-SE's are shipped with a 5 inch DD which is the same one that the Tek "Frat Bros." series machines use. Preliminary testing indicates that the 11 inch DD which is part of that same series is also electrically compatible, although we do not have 19 kHz production experience yet to actually guarantee that. We are watching the situation closely to see if this frequency difference is going to cause problems, but these are wideband searchcoils by design and so far it appears that aligning them at 7.8 kHz will be just fine at 19 kHz. If production experience reveals a problem with fallout we'll start aligning GB platform searchcoils at 19 kHz; until then there isn't any reason to do so.
The concentrics from the "Frat Bros." series are NOT wideband coils and are presumed not compatible with the 19 kHz machines. It's possible someone may stick a concentric searchcoil on a 19 kHz platform machine and report that it works, but if it does they either got lucky, or they aren't as lucky as they think they are.
Sorry, I'm not prepared to answer questions about the Gold Bug Pro. That's in the future, and trying to predict what already happened a week ago is difficult enough.
--Dave J.
The concentrics from the "Frat Bros." series are NOT wideband coils and are presumed not compatible with the 19 kHz machines. It's possible someone may stick a concentric searchcoil on a 19 kHz platform machine and report that it works, but if it does they either got lucky, or they aren't as lucky as they think they are.
Sorry, I'm not prepared to answer questions about the Gold Bug Pro. That's in the future, and trying to predict what already happened a week ago is difficult enough.
--Dave J.