Mike Hillis
Well-known member
I'm moving this onto it's own thread. Sometimes when you have a lot of options to chose from it helps have a little understanding about the options. I hope the following is helpful: 
Need to remember that the audio and visual modes are processing the target signals independent of each other. It is like having two separate machines operating together at the same time.
At first glance when you are choosing a "# of Tones" audio selection to use in the Disc mode, you may think that you are just selecting how many tones you'll hear for the tone id. You can choose between 1, 2, 3, 4, and multi-tone, Tone Id. But what you are really selecting along with the above is how you want the audio mode to process the signal response for the audio side of the detector. And along with that, two modes also change the way the visual id processes the signal.
If you go back to the manual you will find that you can choose between several audio signal processes: Continuous, sampled, or some combination of both.
The 1, 1+, and dP audio modes use continuous signal processing for the audio. You get to hear the entire signal from leading edge, peak, to falling edge of the signal. There is no internal threshold that limits how much of the signal you hear so you get to hear everything that the target might produce. Your sweep speed combined with the signal strength and target position under the coil (and nearby trash) is the only limiting factors as to how much information the audio can convey. Remember that the audio is separate from the visual id so it is quite possible to get good audio signals without a visual ID on the deeper signals. Each of these three audio modes also offer their own special characteristics to work with the signal processing. 1 is a nice single tone that doesn't offer any distractions. Nice, Plain, and Simple. 1+ adds a little more information in that the VCO aspect immediately tells you signal strength. For the tone lovers like me, the dP mode gives the nice full audio processing with the addition of multitone conductive id. These are the modes to use when you are wanting to look really deep but still need to use some discrimination (otherwise go to the All Metal mode)
The 2+ mode uses a split sampling process. Continuous processing for the high tone side, but a combination of continuous and sampled for the low tone iron side. One aspect of 'Sampled' means that there is an internal threshold that has to be reached in order for a signal to produce a audio response. This gives you a nice long audio look at the non-ferrous signals, but helps to keeps the ferrous responses short. This in combination with the Biaxial coil is what makes this mode so good in the iron. The natural separation ability of the DD coil is enhanced by the quick response time of the T2 and then further enhanced by keeping the ferrous responses short means less iron masking and better iron see through ability. High conductors in medium to heavy iron trash will give a tight, short, cutoff high tone however, so even though the signal processing is continuous, the amount of iron will have an effect.
The 3 and 4 tone modes also use a combination of continuous and sampled signal processing. It works just like the 2+ ferrous response mentioned above, except it affects the entire discriminatory range. Both of these modes work really well in the higher trash areas and still get pretty decent depth. These modes also tie in with the visual id the best.
The 3b mode also uses a combination of continuous and sampled signal processing but with a tighter threshold on the sampled side that requires a more stable peak signal response. This mode was specially designed for sites that that have lots of the steel crown style bottle caps, or any area that may require a tighter peak signal target id.
The Visual ID side only uses a sampled signal process. It works on a different sampling process than that of the audio modes and is the same for all audio modes but one. When you chose the 3b audio mode, you are also selecting to use a Visual ID mode that uses a tighter sampling process for the visual id. This is probably the least independent mode you can select and I tend to think that the same sampling process is used for both the audio and visual id modes.
I have thoughts that the dP mode also changes the visual id sampling process just by the amazing way the audio can sound so good, yet not give a visual.
Another sweet thing about these audio modes is that it is very easy, fast and simple to switch between them and test signals with different modes. Once you understand the processing piece it is easy to switch between a processing mode to see if you can further enhance that deep signal you aren't quite sure about, or attempt a better id in the trash.
HH
Need to remember that the audio and visual modes are processing the target signals independent of each other. It is like having two separate machines operating together at the same time.
At first glance when you are choosing a "# of Tones" audio selection to use in the Disc mode, you may think that you are just selecting how many tones you'll hear for the tone id. You can choose between 1, 2, 3, 4, and multi-tone, Tone Id. But what you are really selecting along with the above is how you want the audio mode to process the signal response for the audio side of the detector. And along with that, two modes also change the way the visual id processes the signal.
If you go back to the manual you will find that you can choose between several audio signal processes: Continuous, sampled, or some combination of both.
The 1, 1+, and dP audio modes use continuous signal processing for the audio. You get to hear the entire signal from leading edge, peak, to falling edge of the signal. There is no internal threshold that limits how much of the signal you hear so you get to hear everything that the target might produce. Your sweep speed combined with the signal strength and target position under the coil (and nearby trash) is the only limiting factors as to how much information the audio can convey. Remember that the audio is separate from the visual id so it is quite possible to get good audio signals without a visual ID on the deeper signals. Each of these three audio modes also offer their own special characteristics to work with the signal processing. 1 is a nice single tone that doesn't offer any distractions. Nice, Plain, and Simple. 1+ adds a little more information in that the VCO aspect immediately tells you signal strength. For the tone lovers like me, the dP mode gives the nice full audio processing with the addition of multitone conductive id. These are the modes to use when you are wanting to look really deep but still need to use some discrimination (otherwise go to the All Metal mode)
The 2+ mode uses a split sampling process. Continuous processing for the high tone side, but a combination of continuous and sampled for the low tone iron side. One aspect of 'Sampled' means that there is an internal threshold that has to be reached in order for a signal to produce a audio response. This gives you a nice long audio look at the non-ferrous signals, but helps to keeps the ferrous responses short. This in combination with the Biaxial coil is what makes this mode so good in the iron. The natural separation ability of the DD coil is enhanced by the quick response time of the T2 and then further enhanced by keeping the ferrous responses short means less iron masking and better iron see through ability. High conductors in medium to heavy iron trash will give a tight, short, cutoff high tone however, so even though the signal processing is continuous, the amount of iron will have an effect.
The 3 and 4 tone modes also use a combination of continuous and sampled signal processing. It works just like the 2+ ferrous response mentioned above, except it affects the entire discriminatory range. Both of these modes work really well in the higher trash areas and still get pretty decent depth. These modes also tie in with the visual id the best.
The 3b mode also uses a combination of continuous and sampled signal processing but with a tighter threshold on the sampled side that requires a more stable peak signal response. This mode was specially designed for sites that that have lots of the steel crown style bottle caps, or any area that may require a tighter peak signal target id.
The Visual ID side only uses a sampled signal process. It works on a different sampling process than that of the audio modes and is the same for all audio modes but one. When you chose the 3b audio mode, you are also selecting to use a Visual ID mode that uses a tighter sampling process for the visual id. This is probably the least independent mode you can select and I tend to think that the same sampling process is used for both the audio and visual id modes.
I have thoughts that the dP mode also changes the visual id sampling process just by the amazing way the audio can sound so good, yet not give a visual.
Another sweet thing about these audio modes is that it is very easy, fast and simple to switch between them and test signals with different modes. Once you understand the processing piece it is easy to switch between a processing mode to see if you can further enhance that deep signal you aren't quite sure about, or attempt a better id in the trash.
HH
