what troubles with the bb-2s ? I was very impressed with those , not only for the fact that you can just set them for a nice touch of echo/reverb in the radio and leave well enough alone after that not having to use the dual controls, but that they will fit very nicely in the 520s and smaller radios like that without a sweat. Weather or not they appear to "amplify" the audio or not , the few I have used , were all nice. it's kind of like i said before , some are surely better then others for what they do , but lets face it here , you either want to make a bunch of noise with them (like the TRB-1's will allow you to do along with the LTs ) or you just want to set them for that nice echo/reverb in your audio and leave well enough alone , and as I said , you can get that much out of a run of the mill Astatic board or a DM-452s mic at the same cost or less. Not to get of subject here , but pound for pound and the cost of a DM-452 , those mic's have impressed me since day one !(whatever name they have on them) They seem to work well on any radio I ever put them on , weather they were swing kitted , SSB'ed or just plane tuned for performance , with there slider control on the front and the volume and reverb control pots inside the mic , these 20.00 mic's do a fine job for what they are. I swear by them for what they are, although depending on how much of a bucket mouth one might be ? A good 9 volt battery will go a fairly long way on those. (bucket mouths beware) , echo mic's eat batterys like a bowl of peanuts on a crowded beer bar counter.
