A Question Of Audio Response

[CPT_GhostLight]

I watch metal detecting video for entertainment and to gleen useful information. I don't usually watch videos testing detector against detector, but prefer videos testing detectors against their true adversary, the ground, and in this case the environment.

I don't usually have too many problems on the D2 with EMI, especially with the 9" coil, but I've been dialing in my 11" coil lately and hit some horrible EMI in a park I had not hunted before and Frequency Shift could not tame it. I tried all the usual methods like running several Frequency Shifts, lowering the Sensitivity, switching programs, etc, but nothing helped.  I remembered seeing a video in which Paystreak was discussing taming the V1.0 update and in particular addressing EMI by reducing the Audio Response.

I never thought to try that until I hit this particular park and it's very large strong EMI area. I used to set the Audio Response to 5 in V0.71 and have lowered it to 4 in V1.10 and have been happy with that. I pretty much considered AR to be a static setting across all programs. Now I am reconsidering that. So, I put my usual Fast program settings back to where they were with Sensitivity at 95, Silencer and B.Caps at 0, Max Freq at 40, and lowered the Audio Response one number at a time to see if it would affect the EMI chatter and it did. With AR at 2 the EMI chatter was greatly reduced and at 0 it was almost unnoticeable.

I was concerned that lower Audio Response settings would reduce detecting depth, but that didn't seem to be the case. Even with AR at zero, I was able to hear targets just fine, but I ran AR at 2-3 just out of an abundance of caution and hit targets to around 6 inches or so even in the mild chatter of 3. This was an eye opener for me. I will have to experiment more with targets at depth to satisfy my own mind, but I like the possibilities.

Has anyone else experiment with Audio Response?

Here is what I was able to find in the monsterous EMI of that park.

[bigtim1973]

Good info. I saw paystreak doing that as well in his videos. 

 

By chance did you try the mono program in that bad emi area and if so did it tame it down any or was it still a nuisance?

[NCtoad]

Yep, lowering audio response really helps to quiet emi.  In most of the factory programs it’s set at 4.  I usually run it at 3 or 2.   The modulation really helps with telling how deep something is.  It’s an audio depth meter for me.  

[CPT_GhostLight]

2 hours ago, bigtim1973 said:

Good info. I saw paystreak doing that as well in his videos. 

 

By chance did you try the mono program in that bad emi area and if so did it tame it down any or was it still a nuisance?

I did try the 17kHz Single and it was chattery too, but I did not try the other single frequencies.

[Lodge Scent]

Very interesting CPT. I have not tried that with AR. Usually keep mine at 4 or 5. But I will try what you did.

[ColonelDan]

On 7/17/2023 at 3:30 PM, CPT_GhostLight said:

I watch metal detecting video for entertainment and to gleen useful information. I don't usually watch videos testing detector against detector, but prefer videos testing detectors against their true adversary, the ground, and in this case the environment.

I don't usually have too many problems on the D2 with EMI, especially with the 9" coil, but I've been dialing in my 11" coil lately and hit some horrible EMI in a park I had not hunted before and Frequency Shift could not tame it. I tried all the usual methods like running several Frequency Shifts, lowering the Sensitivity, switching programs, etc, but nothing helped.  I remembered seeing a video in which Paystreak was discussing taming the V1.0 update and in particular addressing EMI by reducing the Audio Response.

I never thought to try that until I hit this particular park and it's very large strong EMI area. I used to set the Audio Response to 5 in V0.71 and have lowered it to 4 in V1.10 and have been happy with that. I pretty much considered AR to be a static setting across all programs. Now I am reconsidering that. So, I put my usual Fast program settings back to where they were with Sensitivity at 95, Silencer and B.Caps at 0, Max Freq at 40, and lowered the Audio Response one number at a time to see if it would affect the EMI chatter and it did. With AR at 2 the EMI chatter was greatly reduced and at 0 it was almost unnoticeable.

I was concerned that lower Audio Response settings would reduce detecting depth, but that didn't seem to be the case. Even with AR at zero, I was able to hear targets just fine, but I ran AR at 2-3 just out of an abundance of caution and hit targets to around 6 inches or so even in the mild chatter of 3. This was an eye opener for me. I will have to experiment more with targets at depth to satisfy my own mind, but I like the possibilities.

Has anyone else experiment with Audio Response?

Here is what I was able to find in the monsterous EMI of that park.

CPT,  I’ll never argue success and you’ve certainly had your share based on those photos 

In my case, I have very little EMI or chatter on our beaches. The little we do have, I can neutralize with frequency scan and sensitivity adjustments as needed. 

Regarding Audio Response, I keep mine at 7.  Why?  I want to hear every good target really sing out and I personally don’t care about an auditory depth indicator.  The beach sand is easily dug so I just keep digging until I find whatever it was singing out to me!!!😉

Just the view from my sandy foxhole….

[abenson]

Yep have used audio response a number of times to calm EMI. Also a good idea to lower it in heavy iron too reduce falsing. Usually run mine at 3 or 4 but have been down to 2 at times.

[AlwaysCocaCola]

I use AR from 0 to 2 on all places with trash. It can be both modern and old places. In addition, I use the high overall volume in WS6 and the equalizer functions. This helps to hear even weak signals while maintaining sound modulation.

[midalake]

13 hours ago, ColonelDan said:

Regarding Audio Response, I keep mine at 7.  Why?  I want to hear every good target really sing out and I personally don’t care about an auditory depth indicator.

I run an Audio Response of 6 at the beach. I found with all of the depth testing we did the odds of missing deep targets increases greatly if the Audio Response is lowered. In fact, this is one setting that allows the Deus 2 to be better than the Equinox on depth. 
If it was not for the black sand at my location, I am confident the Audio Response would be 7.  

[UKD2User]

3 hours ago, midalake said:

I run an Audio Response of 6 at the beach. I found with all of the depth testing we did the odds of missing deep targets increases greatly if the Audio Response is lowered. In fact, this is one setting that allows the Deus 2 to be better than the Equinox on depth. 
If it was not for the black sand at my location, I am confident the Audio Response would be 7.  

I agree, I don't like lowering AR much below 5.

Maybe I'm just lucky, I find it's very unusual to have EMI so bad - over such a large area - and having fairly benign soil/sand generally - that I need to "detune" the machine.

Something that all manufacturers could usefully do is get someone on their engineering teams with a deep understanding of psycho-acoustics.  I think that, given the laws of physics and the current state of the art, the real progress yet to be made is in helping the user "hear" good targets better, at whatever depth, than the "trash".

e.g. this kind of thing: https://en.wikipedia.org/wiki/Auditory_masking