There are many ways to convert an acoustic kit into an e-drum kit. Either trough rim triggers attached from above the head, or through in trigger systems, mounted inside the shell. All those systems will work, but in addition to provide positional sensing for advanced Roland modules like the TD-12 or TD-25, the trigger cone has to be in the center of the pad. There are various systems that provide this solution either through a bar, a plate or a spider construction. Most of them are however limited to 1 shell diameter.
My idea was to create an in trigger system that is not limited to only one shell size with a centered trigger cone. There is, however a system on the market with slideable arms, but I wanted my construction to be more simple. Making use of the tools I had at hand, including screws, bolts, and a heat gun (similar to the https://shrinkwrapcontainments.com/p-34-shrinkfast-998-ul-heat-gun-kit.aspx option), I managed to make my conversion work. The system I came up with, has a big aluminum plate in the center, which is held in place by either 6 or 8 aluminum arms. This number depends on the lug number of the particular drum shell. 6 and 8 are simply the most common lug number cancellations.
The plate has holes for both constellations. Each arm is mounted to a custom aluminium angle. Those angles are attached to the lugs directly with a long M4 screw. Each angle has 2 holes in the arm, to provide more mounting options. All metal parts except the screws are made out of aluminum to decrease the weight of the system. The arms have windings for an easy installation process. Their length is calculated to apply the trigger system into every drum size from 16′ to 10′.
The innovative feature of the systems is to make these arms rotatable. Besides being flexible it has the advantage that even the cable from the air hole to center could have a consistent length.
The mounting arms can be installed from either the bottom side or above to the central plate and the angles. The angles can also be applied in 2 different ways per screw. That makes the system extremely flexible in height setting.
The trigger cone itself is vernier adjustable by 3 elevating screws. The head trigger plate can be lifted up or down with a stepless transition. The plate for the head trigger is isolated through 3 rubber joints against vibrations coming from the shell. This is really important as an accurate triggering would not be possible without this rubber dampening system. 2 counter nuts on each screw provide the rubber damper from moving downwards.
The elevation screws are applied into blot nuts with a long internal winding. These screws can each be blocked by counter nuts. Cone and piezo are from R-drums. Both pieces are connected to a 3,5 mm jack plug. The reason for this construction is that 3,5 jack cables usually fit through conventional air vents. That means there is no need to drill a hole into the shell. I provided a video about different adapter cables for only this purpose.
Installing the system:
1st step is removing one row of the lug screws and applying the custom angles. The original lug screws cannot be used, as the angle plate is really thick. The screws get applied with a big washer and a lock washer, to prevent the screw from getting loose. The trigger system needs as many arms as the lugs are on the shell. In this case we used only 6 arms. The arms get mounted by M5 screws including washers and lock washers. They will not get tightened yet. You may even want to consider using Speed nuts for this instead of lock washers and nuts as they do the job of both, are easy to install and are easy to disassemble.
How arms and the angels are mounted depends on the shell. The top of the triggercone has to have approximately the same height than the bearing edge. The arms will get connected to the angles. As the drum in this case is really small, it makes more sense to use the inner holes of the angles. Screws will hold the arm in place. An all screws are tightened, the height of the trigger cone needs to be fine adjusted.
The counter nuts are getting unlocked and the screws can be twisted to move the head trigger either up or down.
The top of the trigger cone has to be 1,5 mm higher than the bearing edge of the shell, to get the best trigger result. As soon as the height is adjusted, the counter nuts can be tightened again. It is important that all 3 bolt heads adjust to the same height level.
A special type of cable is needed if the shells air hole is not getting removed. There are a
lot of 3,5mm jack plugs out there who fit through conventional air holes. This is why the system itself provides a 3,5 jack plug. The cable can be connected and should be tied to the system with cable ties. For connecting a different module than a Roland V-drum Module, it might be necessary to use a different cable, as the head rim trigger circuit is not the same for every electronic drum module.
The second last step is applying the mesh heads. It is recommended to use at least a dual ply mesh head, especially if the connected to a Roland module that provides positional sensing. The resonance mesh head is only needed for optical reasons and to mount the bottom rim. It doesn’t matter what kind of mesh head is used. The pad is almost ready, only a rim noise eliminator is required to preserve the sticks. It might be necessary to change the pad settings for a perfect trigger result.
- Pad Type: PD-125
- Sensitivity: 13
- Threshold: 1
- Rim Gain: 3.2
- Rim Shot Adj.: 4.2
Watch a video about the Flextriggersystem: