Bait Ban
Member
You could look at transducers just like speakers and make a judgement about them just based on power rating, but that gives very little indication of performance. The true measure of performance lies in the "Q" number... Because transducers are not just speakers, but must also be microphones.
An electrical signal generated by your head unit vibrates a piezo ceramic element inside the transducer, creating a sound wave through the water. Just like a bell, there is resonant vibration after the signal is dispersed through the water column. The lower the "Q" number, the faster "the bell stops ringing" this is important because Piezo electric element must "listen" for the return echo. The echo vibrates the element, which creates an electric signal, that the sounder module will interpret as fish and bottom contours on your display. Transducers with lower Q numbers generate a cleaner image, with less distortion and interference in the sonar image; you can then in turn increase the sensitivity setting on your display and make more efficient use of the energy your sonar is outputting..
The TM-150 has a very low Q number of 2 compared to 24-30 of the P-66. I would expect better definition and target separation for the TM-150 at shallow depths (ie identifying salmon around a bait ball, or fish suspended just off of bottom, and have less surface noise, but expect the p-66 to deal with plankton and algae blooms, and hold bottom in deeper water. Unfortunately I don't have a TM-150 to make the comparison..
An electrical signal generated by your head unit vibrates a piezo ceramic element inside the transducer, creating a sound wave through the water. Just like a bell, there is resonant vibration after the signal is dispersed through the water column. The lower the "Q" number, the faster "the bell stops ringing" this is important because Piezo electric element must "listen" for the return echo. The echo vibrates the element, which creates an electric signal, that the sounder module will interpret as fish and bottom contours on your display. Transducers with lower Q numbers generate a cleaner image, with less distortion and interference in the sonar image; you can then in turn increase the sensitivity setting on your display and make more efficient use of the energy your sonar is outputting..
The TM-150 has a very low Q number of 2 compared to 24-30 of the P-66. I would expect better definition and target separation for the TM-150 at shallow depths (ie identifying salmon around a bait ball, or fish suspended just off of bottom, and have less surface noise, but expect the p-66 to deal with plankton and algae blooms, and hold bottom in deeper water. Unfortunately I don't have a TM-150 to make the comparison..
