G2 Production Updates

Hi everyone, Update #10 is a YouTube video, click here to watch.

We cover BackBeat functionality, expected timeline, accessories, and components in house.

Hi All,

We hate to bear bad news, but need to let you all know the G2 will not be shipping in October as planned. 

As noted in previous updates, due to chip shortages we had to redesign the circuit board, which has had other compounding effects incurring further design and tooling changes.

In a nutshell, we underestimated the redesign and production time. As such, we project to be shipping in January. This is based on our suppliers' timeframes and our assembly process here in the US. 

We are bitterly disappointed that we have not delivered on our timeframe. We want you to have the next generation BackBeat as much as you do.

Our continuing goal is to keep on top of our suppliers regarding delivery. We're already prepping our assembly process for when the components arrive.

The spring/magnet assemblies are currently in transit across the Pacific Ocean.

We will continue to share photos of components as they come in, as well as more detailed production/assembly updates.

FAQ

Does anyone have a G2 unit?

No one has a G2 unit. Any social posts you see are the original G1 BackBeat.

Are there any G1 units available?

No, they are sold out. Our focus is 100% on building and delivery of G2.

Is it possible you'll ship sooner than January? 

Yes, it's an outside possibility. 

Will any of this increase the unit price?

Absolutely not.

Thank you for your patience and continued support. We're making the best possible product we can for your enjoyment. As always, if you have specific questions, you can email us directly at hi@getbackbeat.com.

From the Low End

BackBeat

Hi and welcome to update #8!

Components are slowly starting to trickle in

USB charging cables are shown below:

The charging connector on BackBeat is USB-C with the other end being USB-A connectable to a standard USB port.

We've set up the maximum charging current to be 1.5A which balances charging speed and battery life. 

The Voice Coils have also arrived:

These voice coils are 4.2ohms DC resistance. The class-D amp has an impedance range of 4-8ohms.

For the BackBeat system 4.2ohms provides the best balance between current draw (directly proportional to the electromagnetic force which drives the magnet), wire size, power, and battery charge life.

Spring/Magnet production

The springs that provide the restoring force and centering for the magnet assembly have been completed, and are being incorporated with the magnets.

The magnet assemblies themselves are almost complete (expected to be completed by the end of this week), we should have some photos to share soon.

Bluetooth module testing

As mentioned in a previous update, due to component unavailability we had to switch manufacturer for our Bluetooth module. This set us back significantly due to time taken for redesigns and testing.

As well as providing Bluetooth capability, the module serves as the microprocessor "brain" for all BackBeat operations.

We've received sample revised circuit boards with this module, and have used them for testing to prepare for mass manufacturing.

Over the last several weeks we have been testing this new Bluetooth module and are happy to say the module has passed our requirements.

As such, we immediately secured orders for the modules and have them in hand for the full circuit board production.

Cable connections

Again as mentioned in a previous update, we added the through 1/4" connection which provides a similar signal chain path as the original G1 BackBeat:

And just like G1, these 1/4" connections are hard-wired. So should the battery die mid-performance, your signal path remains unchanged. 

So you can use your own cables or have the option to use the BackBeat-specific cable, more details in a future update.

Touchpad Controls 

Note: although the functionality is the same, this is a sample touchpad we received months ago and is not the final controller.

Mode Button - cycles through different modes:

1. pressing the logo turns the unit on. The initial state retains the same levels as the previous settings. This is equivalent to taping the G1 knobs in place that we have seen some folk use!

2. battery mode - green LED blinks showing current battery state of charge, which in the video shows about ~90%.

3. pad setting. No green LEDs means no pad (used for setting input levels for passive and active basses).

4. Signal Input. Bass input thump strength, indicated by green LEDs from mute to max (LEDs from video indicate approx. 20% power).

5. Input Headphone. Bass signal headphone volume, indicated by green LEDs from mute to max (LEDs from video indicate approx. 30% volume).

6. Auxiliary Input. Aux input thump strength, indicated by green LEDs from mute to max (LEDs from video indicate approx. 10% power).

7. Aux Headphone. Aux input headphone volume, indicated by green LEDs from mute to max (LEDs from video indicate approx. 80% volume).

With these controls you can see that a big improvement over G1 is being able to individually mix the Auxiliary input, whether it be the rumble or the headphone output.

Here's another video demonstrating the step control for the rumble and headphone output:

Firmware Development

For those interested, here's the block diagram showing the main circuit board components and signal paths:

All the major blocks and interconnecting signal blocks have been proven out as functional with the new Bluetooth module/microprocessor.

We have some small details to iron out but as you can see from the videos, the firmware is mostly completed. Details include adjusting dB steps for each button push, plus setting maximum dB for the thump and headphone volume. 

Thats it for now! We're still expecting to start shipping in October. Thank you for your patience, and as always if you have any specific questions, you can email us directly at hi@getbackbeat.com.

From the Low End

BackBeat

Welcome to the latest update on BackBeat G2! 

A. Shipping

At the moment we are cautiously optimistic that shipping will start in October. Why the delay? Unsurprisingly our two main battles are Covid and chip shortages:

Covid

Several of our suppliers in China had to shut down for several weeks due to covid outbreaks. This affected communications, design, and shipping.

One of our key team members was very sick for a couple of months. We're very thankful that he and his family have recovered and are doing well.

Chip Shortages

This is a historic time in the chip supply business, affecting the design and manufacturing process of circuit boards.

Between design and ordering, we've had several chips become unavailable. The scarcity of components requires research to find new components, which requires time to redesign.

New components also need to be tested and verified for usage. It then takes more time to redesign the electrical schematic, verify again the component availability, and make sample circuit boards for further testing.

We've taken the proactive step of securing key individual components ahead of time. It used to be when you designed a PCB, components were immediately available when ordering. That's not the case at the moment and it's just the reality of the world we're living in.

B. PCB design change

Given the effort required to redesign the PCB, we decided to add an extra feature. We'll be adding a pass-through jack like G1 has:

This will allow you to have 2 main options for connecting BackBeat to your bass:

1. use the BackBeat custom cable that will be provided standard with the unit. 

2. use your own cables.

As components start arriving we'll have more details including videos on connection options.

As stated above, we needed to make PCB changes related to new components and revised layouts, so this feature add doesn't add any cost or time. 

You can also see from the screenshot above that we have relocated the headphone, auxiliary, and USB charging jacks.

C. We're removing the RGB LED 

In testing we found the RGB LEDs required too much current draw, which dramatically reduces the battery charge.

We could reduce the current draw to more manageable levels but then there's not enough light coverage from the RGB LED to make it a worthwhile feature.

So we plan on making the logo a very subtle white, and still use it as the on/off indicator. We're bouncing around the idea of providing backlit transparent color stickers of your choice to customize your BackBeat.

Also note, the LEDs in general will be very low power. They won't be distractingly bright, they'll just be there as a visual indicator.

We'll have more detail on the user interface in a future update. 

D. Component ordering

We have the magnets, springs, voice coils, USB charging cables on order and are waiting on delivery.

Rising commodities prices and shipping delays have also impacted sourcing these components comprising the G2, but not nearly as much as the circuit board components. 

E. Touch Pad progress.

Firmware that controls the touch pad is about 90% complete. There are several tweaks that we're making as testing progresses. 

The photo below is the BackBeat in battery mode. The four out of five LEDs are indicating approximately 80% charge available. 

F. 4-blade Spring testing

Following up from update #6, the 4-blade spring design has proved to be a success. We have some nice, even deflection without magnet/voice coil interference. 

The rumble is NICE! We're getting it dialed in physically with the spring/magnet/enclosure design as well as adjusting EQ values in software.

That's it for now! We've had several challenges, but are excited to continue making progress on delivering the G2 BackBeat.

Keep looking out for these updates on our website, we'll also start emailing them out.

As always, feel free to reach out to us with any questions.

From the Low End,

BackBeat  

Testing

This has been an intense time for testing the individual components and putting them through their paces.

Our DSP software allows us to rapidly add elements to our program that affect the thump intensity output force, response over frequency ranges, headphone volume and EQ, etc.

This is our current DSP schematic:

The original BackBeat G1 had a low-pass filter only in the signal chain. This provides a frequency response between approx. 20-200Hz. It also had a natural frequency resonance around 60-80Hz. The rumble response is significantly more pronounced around these frequencies.

For G2, we've included a compressor in the transducer thump chain. Much like a compressor in an audio signal chain, it will smooth out the thump response over a wide frequency range, so the higher resonance levels will be lower, and the lower will be higher. 

EQ setting are also easy with the DSP. We have a low pass filter for the thump response range. We'll also have the future ability (through the app) to change EQ settings. For example, you'll be able to add extra bass in the headphone output if you're using small ear bud headphones.

Programming PCBs

We're close to finishing up our programming testing which involves:

-verifying component functionality.

-programming bootloader and softdevice onto the main BT chip.

-flashing the firmware.

The firmware is the custom software that will make BackBeat function. You will interface with the firmware through the membrane switch buttons and also eventually though the app.

We have also completed the design and are in the middle of constructing the programming and test fixture for the PCB's. This is a HUGE part of the process since the PCB is the brain of the whole unit and this process will ensure the same quality across all boards.

Spring redesign

You may have seen our 3-blade spring design previously. Through our physical testing we could tell there was an issue with the spring around 60Hz. It tended to wobble sideways and not in its intended up-down motion. That wobble caused the magnet to hit the voice coil, making noise and slightly damaging the coil.

We performed a finite element analysis (FEA) of the spring and magnet combination. Sure enough we found a natural modal frequency at 61Hz:

The solution is quite simple and that's to go to a 4-blade design:

The only change we need to make is to add a post in the enclosure to accommodate the 4th blade. FEA runs show there aren't any undesirable modal frequencies in G2's operating range. The shape of the enclosure, the magnet, the voice coil all remain the same.

Thats it for now, watch for our next update in a couple of weeks, we have a lot more cool stuff to report!

Component availability

Yep, we've been hit with the worldwide chip availability bug. Specifically, our Bluetooth Module provider is completely sold out of their modules, here in the US and overseas. 

For the last 5-6 weeks we've devoted our time to evaluating alternate components. Think of the Module as a car that needs to get us from A to B. Instead of buying a Ford, we're designing our trip with a Tesla. We still need 4 wheels, engine/motor, steering wheel, etc to get to our destination, but what we use will be different than originally designed.

PCB redesign 

As such, we've needed to redesign the circuit board schematic as well as the physical board layout.

In principle nothing has changed from our previous design however we need to make sure all the component pins and connections line up correctly electrically and physically.

There are also a handful of other smaller components we've had availability issues on, however we've been able to find alternates for these.

Although this has set us back a bit, it's difficult to know exactly how it will impact shipping moving forward. We'll keep you up to date on how thats looking through these communications.

Component purchase

In the past, components were readily available at the time of circuit board manufacture. Now, we're constantly chasing our suppliers to follow-up on chip availability and get in the queue for upcoming shipments.

To date we've already prepurchased several components including:

-Class D amp chips.

-Digital Signal Processing chips.

-charging chips.

We anticipate not having to make any more changes and feel we are ahead of component shortages.

In our next update we'll talk about code and programming, testing, and more!

No, we haven't hired the Predator....(yet)

This image is courtesy of a FLIR (forward looking infrared) camera which picks up surface temperatures and, in this case, converts them to colors.

You can see the charging chip as the hottest component at 114F (46degC) with heat radiating out and dissipating into the PCB. This test is during a full recharging cycle and ensures we are well below chip junction and operating temperatures.

We've also confirmed proper Li-Ion battery constant current/constant voltage charging parameters. 

The blue curve (current) shows constant current charging while the green curve (voltage) rises to its max voltage (4.2V). Once it reaches 4.2V, voltage remains constant as the current drops until reaching maximum capacity.

The charging capability in G2 is a substantial upgrade to G1. We have better protections, safety, and the ability to eventually diagnose any issues through the app.

We also have an on board Fuel Gage that will help you see battery life. We can communicate this visually through the LEDs on the touch pad as well as more accurately through the app.

The brain of BackBeat is the Bluetooth module. The module has memory storage which will contain all the code for the components on the BackBeat circuit board. 

Right now we're working on finalizing the Battery Charging chip registers:

 These set the parameters for charging such as:

-maximum charging current.

-input voltage limit.

-input current limit.

-termination current limit.

-enable and disable charging.

There's also a host of Status and Fault information which will help us diagnose battery/charging issues. This is all to ensure proper charging, safety, charging efficiency, and prolonged battery life. 

The battery chip also integrates with the Coulomb counter which will help you determine battery life and charging status. In battery mode, the Level Indicator LEDs on G2 will approximately indicate how much charge is left in the battery:

In the app, this will be a lot more accurate and provide battery life indication like you would get for a phone battery.

As always if you have any questions, drop them down below!