Why Add a Volume Knob to your Clark board? Here's Why!
Posted: Sun Sep 29, 2024 7:48 am
With my Clark TK50ESP board, the tank's volume control is digitally controlled from the FlySky transmitter, but it is not an analog-style volume control like on my other tanks... instead, it digitally reduces the number of amplitude bits used by the board's D>A (digital to analog) converter, prior to outputting sound to the speaker. This has the result of making the audio sound best only at its loudest volume, but progressively worse & noisier as the volume gets lower... the sound becomes noticeably more "grainy" & distorted as you go lower in volume. Of course I was dismayed that my nice new board had this limitation, since leaving the tank at full volume all the time just to get the best sound quality is ridiculous; it'll just about take your head off at close range!
So, I installed an analog volume knob in my Mato Tiger I, shown here... choosing the right one is important since you don't want it to be too 'restrictive' at the max setting, in case you DO want full ear-splitting volume. I took my multimeter to a local electronics surplus store & tested a handful of volume pots until I found the right one, with an 'undimmed' maximum setting & a nice smooth roll-off as you go down from there; others jump from loud to quiet way too suddenly. Now I just leave the Clark set to max volume & tweak the knob when necessary, and it sounds consistently good at any level.
You can see here that the new volume knob is easily accessible through the Tiger's left-side engine cooling fan hatch:
And here's the interior side view... also showing my twin speaker setup (more on that after the photo):
These 'dual-speaker' Heng Long units sound better than any similar-sized speakers I've tested, but note that they are not actually 'dual-speaker' - the second 'speaker' is just a passive radiator, which gives them far better bass & richer sound than the previous generation of HL speakers. People who claim that these can come wired out-of-phase are incorrect since no wiring exists for the radiator, but sometimes these do have a loose speaker cone (easily remedied) which can make them sound a bit 'thin'. However, when adding a second speaker like this (wired in series to raise the total resistance, not drop it), you do have to pay attention that the two speakers are in phase with each other.
The second speaker & the volume knob were added together in the same path 'non-destructively' by making a wiring harness that easily plugs in to the board, creating a series circuit loop including both speakers & the potentiometer. The wiring harness can be removed without a trace.
So, I installed an analog volume knob in my Mato Tiger I, shown here... choosing the right one is important since you don't want it to be too 'restrictive' at the max setting, in case you DO want full ear-splitting volume. I took my multimeter to a local electronics surplus store & tested a handful of volume pots until I found the right one, with an 'undimmed' maximum setting & a nice smooth roll-off as you go down from there; others jump from loud to quiet way too suddenly. Now I just leave the Clark set to max volume & tweak the knob when necessary, and it sounds consistently good at any level.
You can see here that the new volume knob is easily accessible through the Tiger's left-side engine cooling fan hatch:
And here's the interior side view... also showing my twin speaker setup (more on that after the photo):
These 'dual-speaker' Heng Long units sound better than any similar-sized speakers I've tested, but note that they are not actually 'dual-speaker' - the second 'speaker' is just a passive radiator, which gives them far better bass & richer sound than the previous generation of HL speakers. People who claim that these can come wired out-of-phase are incorrect since no wiring exists for the radiator, but sometimes these do have a loose speaker cone (easily remedied) which can make them sound a bit 'thin'. However, when adding a second speaker like this (wired in series to raise the total resistance, not drop it), you do have to pay attention that the two speakers are in phase with each other.
The second speaker & the volume knob were added together in the same path 'non-destructively' by making a wiring harness that easily plugs in to the board, creating a series circuit loop including both speakers & the potentiometer. The wiring harness can be removed without a trace.