(11-04-2019, 07:33 AM)zaius Wrote:

(11-03-2019, 10:25 PM)MrTester Wrote: I have included photos of my work, my preferred choice was athletic tape (woven fabric tape, with high adhesive properties).

Have you considered trying friction tape?  It's cotton cloth impregnated with rubber. Once used as electrical tape, it has good adhesion, it's non-conductive, and very durable.  It's generally 15 mil, so it might be thicker without being too thick.

(11-04-2019, 07:04 AM)rick1959 Wrote:

(11-03-2019, 10:25 PM)MrTester Wrote: Greetings PBP friends, 
Tonight I decided to dig inside and see what mechanical/ acoustical improvements I could make to the PBP speaker system. 

Background: Initially when working on my PBP, I noticed when playing audio, the playback was extremely harsh on the ears and a significant amount of resonance in the palm rest (back side of the speakers) My main goal was to observe and find some mechanical isolation solution to improve audio.

Observations: After opening my PBP, I found the following, A simple speaker, isolated from the metal bottom of the laptop (and speaker grill/opening ) by an adhesive foam surround. The back of the speaker (magnet side) is directly adhered to the plastic palm rests, located in place by molded frame apart of the palm rest. 

My initial assessment was that a significant amount of energy was being transferred from the speaker magnet directly into the palm rests, resulting in physical resonance and contributing to the observed acoustical resonance.  Considering the space as tight manufacturing tolerances, any mechanical isolation solution would need to be minimal thickness. With the above comment considering a MFG change could be considered, The cost of such options was in consideration. 

I tested Duct tape, Electrical tape, and athletic tape. My intention was to cut just enough tape, to fit behind the speaker, and isolate it from the palm rest. All produced significant reduction in physical energy transfer into the palm rest. The acoustical improvement is reasonable in my opinion, I would like others to test if this is a significant enough of a improvement. 

I have included photos of my work, my preferred choice was athletic tape (woven fabric tape, with high adhesive properties).

That's excellent!!
And sounds, forgive the pun, that the tape may be what relieves (absorbs?) the buzziness?
Clearer high level volume? Clearer in general?


Here's my thought, unsolicited: How about a drop of rubber cement on the magnet, sufficient to spread wide enough to cover the whole circular area of the magnet? Just enough to insulate the magnet.....

I'm not brave enough, nor have the time to try it right now. However, what do you think? :-)

(11-04-2019, 08:42 AM)MrTester Wrote:

(11-04-2019, 07:33 AM)zaius Wrote:

(11-03-2019, 10:25 PM)MrTester Wrote: I have included photos of my work, my preferred choice was athletic tape (woven fabric tape, with high adhesive properties).

Have you considered trying friction tape?  It's cotton cloth impregnated with rubber. Once used as electrical tape, it has good adhesion, it's non-conductive, and very durable.  It's generally 15 mil, so it might be thicker without being too thick.

I do not have access to any Friction Tape at home or at work currently. I would agree this may be the safest, and most functional option.

---

(11-04-2019, 07:04 AM)rick1959 Wrote:

(11-03-2019, 10:25 PM)MrTester Wrote: Greetings PBP friends, 
Tonight I decided to dig inside and see what mechanical/ acoustical improvements I could make to the PBP speaker system. 

Background: Initially when working on my PBP, I noticed when playing audio, the playback was extremely harsh on the ears and a significant amount of resonance in the palm rest (back side of the speakers) My main goal was to observe and find some mechanical isolation solution to improve audio.

Observations: After opening my PBP, I found the following, A simple speaker, isolated from the metal bottom of the laptop (and speaker grill/opening ) by an adhesive foam surround. The back of the speaker (magnet side) is directly adhered to the plastic palm rests, located in place by molded frame apart of the palm rest. 

My initial assessment was that a significant amount of energy was being transferred from the speaker magnet directly into the palm rests, resulting in physical resonance and contributing to the observed acoustical resonance.  Considering the space as tight manufacturing tolerances, any mechanical isolation solution would need to be minimal thickness. With the above comment considering a MFG change could be considered, The cost of such options was in consideration. 

I tested Duct tape, Electrical tape, and athletic tape. My intention was to cut just enough tape, to fit behind the speaker, and isolate it from the palm rest. All produced significant reduction in physical energy transfer into the palm rest. The acoustical improvement is reasonable in my opinion, I would like others to test if this is a significant enough of a improvement. 

I have included photos of my work, my preferred choice was athletic tape (woven fabric tape, with high adhesive properties).

That's excellent!!
And sounds, forgive the pun, that the tape may be what relieves (absorbs?) the buzziness?
Clearer high level volume? Clearer in general?


Here's my thought, unsolicited: How about a drop of rubber cement on the magnet, sufficient to spread wide enough to cover the whole circular area of the magnet? Just enough to insulate the magnet.....

I'm not brave enough, nor have the time to try it right now. However, what do you think? :-)

Its not a 100% catch all to all audio artifacts, I would like to see if I could apply some native equalization, in addition to the fix. The main concern to isolate most of the energy transfer from the magnet to the palm rest body was my goal. This did improve some of the vibration, We are far from a nice foam filled speaker box, but much closer. 

A dab of RTV silicone or rubber cement would also potentially be cost possible, and easy to transfer into the manufacturing floor.

(05-07-2020, 03:42 PM)TDC_PBP Wrote: I was having a lot of buzzing from my right speaker. I put a strip of masking tape on the back of it, and viola! Great sound at loud volume!

(05-09-2020, 11:23 PM)tllim Wrote:

(05-07-2020, 03:42 PM)TDC_PBP Wrote: I was having a lot of buzzing from my right speaker. I put a strip of masking tape on the back of it, and viola! Great sound at loud volume!

Puzzle on your implementation, please snap a photo. Thanks.