In this article we will review and build the Reverb FPV Frame from ImpulseRC, and compare it to the popular Alien mini quad frame. The Reverb is a racing drone frame designed for Freestyle with top mounted battery, and it’s available in both 5″ and 6″ versions.
The Reverb frame comes as a kit with lots of optional parts you can choose when checking out.
In our reviewed Reverb kit, it contains:
- 4 x 5″ arms (4mm thick)
- Reverb body (2mm and 1.5mm bottom plates, 1.5mm top plate & 2mm camera plates)
- Foam pad for mounting LiPo, antenna tubes and mounts,
- Files for carbon fibre edges
- Gunmetal steel hardware including standoffs
- Red PDB, XT-60 pigtail and two different PDB-FC connectors, one is designed for KISS FC
- GoPro Session mount 3D-printed in TPU with 30 degree tilt
The frame carbon fibre doesn’t come chamfered, and you have to do that yourself if that’s what you prefer. Tools are provided in the kit (2 files), and here is our tutorial on how to file carbon fibre edges in a mini quad frame.
One very interesting feature of the Reverb is the split bottom plates – the front and back are 2 separate plates joined in the centre.
The front bottom plate sits lower than the back bottom plate, and it uses longer standoffs (30mm) to create more space for installing the FPV camera. The plate is also thicker at 2mm I guess that’s because the front usually takes more impact in a crash.
The back bottom plate sits higher than the front plate and it’s using 24.5mm standoffs, the thinkness is 1.5mm.
The arms are sandwiched between those two plates by two screws and press-nuts.
The power distribution board is not a structural element here like it was in the Alien, and it’s attached to the 1.5mm bottom plate with only double sided tape.
The Reverb PDB is simple and plain – there is no current sensor or any other electronics components on it. It has solder pads for power inputs, ESC signal and ground, ESC telemetry and connector header for connecting to a flight controller.
Another interesting feature about the Reverb is the odd number of standoff’s used. There is a single standoff right in the middle that is located between your FPV camera and flight controller.
Camera mount fits any standard size FPV cameras such as the Swift or Arrow. Because it’s designed for FPV Freestyle I guess, camera tilt angle allowed is only up to 45 degree and the slot in the camera mount is a bit short.
The Reverb provides some really cool accessories for mounting your RX antennas – 3D printed mounts that can be attached to the standoffs and plastic tubes.
The optional TPU 3D printed GoPro Session mount can be installed on the Reverb using screws that goes into the 3 standoffs at the front.
Frame assembly is not difficult, but I had to follow the manual very carefully because of the double bottom plate design and I didn’t want to mess it up.
The arms and overall frame structure are extremely stiff, it feels every stiffer than the Alien.
- Bare frame weight – 122.5g
- Frame weight with antenna tubes and With GoPro Session mount 147g
Just like any other frames from ImpulseRC, they always provide non-slippery foam pads for mounting the LiPo battery. It’s cut specifically for the Reverb’s top plate.
Alien vs. Reverb
ImpulseRC are best known for the Alien frame – possibly one of the most popular freestyle frames for mini quads. Make sure to check out our review of the Alien frame.
Is Reverb the “Alien V2”?
Perhaps because of the similarities between the Reverb and Alien, some assumed the Reverb was an upgraded or revised version of the Alien. But according to ImpulseRC, the Reverb is not created to replace the Alien, and they are meant to be two different frames.
These frames do share some design aspects and features, but I personally had very different experience when building them. The Reverb is a more compact frame than the Alien and that really change the flight characteristics and building experience too.
If you are on the fence about the two frames, make sure to check out both of our build logs and flight videos to make a better decision.
Physical differences between the Alien and Reverb
Here is a summary of differences between the two frames:
|Motor Layout||Width is shorter, length is longer, closer to being square||Motor layouts are slightly wider and shorter|
|Dimension||Length: 145mm; Width: 175mm; Motor to motor: 225mm||Length: 135mm; Width: 180mm; Motor to motor: 225mm|
|PDB||Not a structural part of the frame||A structural part of the frame|
|Bottom Plate||Bottom plate split into two||Single bottom plate|
|Standoffs||8 (four 24.5mm, three 30mm)||7 (35mm)|
|Price||About $90||About $120|
Direct comparison of motors arms configuration with 5″ Alien:
Building the Reverb!
I am using the following parts for this build:
- Kiss FC V2 FC
- Spedix 35A BLHeli_32 ESC’s
- ZMX FinX30 2600KV (these are prototype version hence the different bell design)
- TBS Unify Pro HV VTX
- Triumph antenna
- RotorRiot Swift V2 FPV Camera
- TBS Crossfire Micro receiver with Immortal T antenna
I started the build by configuring BLHeli-32 ESC’s. Unfortunately FC pass-through is not supported by KISS FC V2 yet. So in order to program these ESC’s (to flash latest firmware and change motor direction), I had to connect them to an Arduino board and use the BLHeliSuite_32 program. You can also just solder these BLHeli_32 ESC to a Betaflight FC and use FC Passthrough.
All soldering pads on the PDB were pre-tinned first, then I installed the motors and soldered the ESCs to the PDB.
Further Reading: Learn how to do soldering properly
Next I added the XT60 pigtail and a 25V 470uf capacitor to help reduce those voltage spikes and noise created by the ESC’s and motors.
Further Reading: Why add extra capacitor in a mini quad?
I then soldered the cables for the FPV camera and VTX. Because there is no OSD in the KISS FC, I will be getting voltage monitoring from my RunCam’s OSD pin which is connected to the positive power pad on the PDB.
Before installing the KISS FC V2 to the frame, I installed the wire harness provided with the PDB. It is important not to connect the wrong wires to avoid serious damage to your FC!
I soldered the crossfire RX to the FC and finally installed the FC in the frame. I have also soldered the Smart Audio on my VTX to the TLM pad on the KISS FC so I can change VTX settings from my Taranis transmitter.
Further Reading: How to setup VTX Control?
To install the Unify Pro VTX I have to put another heatshrink with antenna wire coming out of the socket side of PCB board. This way can minimize the chance of pulling on the U.FL connector.
I salvage the FC protective plate that came with the Matek F405 AIO FC and attached my Unify Pro on it with double sided tape. The protective plate then sits on top of the FC.
Video antenna was attached to the Reverb’s top plate using zip ties. The FPV Camera is also mounted with some 30 degree of tilt angle.
That was it. The Reverb is completed.
Photos of the complete build
Great things about Reverb
- Good quality of carbon fibre
- Well thought out design with attention to detail
- Very stiff frame – one of the stiffest of frames I’ve built
- Compact and lower profile design
- The flight controller is closer to the line of the props which makes tuning easier
- PDB is not a part of the frame structure and doesn’t have to be used in the frame
- Clean solution for mounting radio receiver antennas
- Attractive price
Things to improve
- Would be nice to include landing pads and lipo straps with the kit
- Maybe provide chamfered edges as a service or option?
ImpulseRC doesn’t released new frames often and they take their time to work on new products to make sure they work. The Reverb is another great design with high level of attention to details. It is more suitable for current components than Alien and given it’s price it is a very solid freestyle frame option IMO.