Project Muse Prototype and Specs are here!

Hey there folks!

Some time has passed since our last update on muse. Today we are bringing all the latest news about our headphones project!

In the past few weeks we were working with the manufacturer of headphones (their name is GrandSun BTW) to kick off the project formally. The reason we picked this manufacturer is because of the driver technology they invented, their capability (Audeze, Master & Dynamics, etc) and willingness to work.


Headphone radio testing facility
Let’s get started!

Muse status update and how will we make a kick-ass pair of cans


First Muse very rough Prototype using 3d printed parts

As I’ve mentioned few times already we’ve partnered with a manufacturer that is not all about cutting angles but rather being ambitions. They also happen to have a unique driver design that beats the normal dynamic driver. We were able to build up a prototype quite quickly with 3d printing testing out basic components and function

How to get kick-ass quality form a pair of over ear noise cancelling cans?

After talking to an awesome guy who is a CTO of a factory behind Audeze we have a much clearer picture :smiley:

Bluetooth headphones are not a simple product. Unlike open back Sennheisers like HD650 designed to work with an external DAC, AMP and DSP, Bluetooth headphones need to have all those components inside to work wirelessly as they need to process digital signal sent over Bluetooth to analog . In Bluetooth headphones it is important to treat all the key features equally as otherwise there is a big risk of making a compromised product. For instance, if we would make the best sounding over ear headset that would have poor Bluetooth connectivity and low level ANC it would end up being a bad product. Let me tell you more about that key parts of the headphone are and why they matter

1. Headphone drivers

Are responsible for creating actual sound by moving air. Different materials for diaphragm and magnets can affect the cleanliness of sound but the type of driver has bigger impact on sound quality. There are various types of drivers, dynamic, planar, electrostatic, hybrid they all have their pros and cons. We will be using a new driver type developed by our manufacturer that allows to dramatically reduce harmonic distortion caused by the conflicting magnetic fields of a normal dynamic driver. (Read more below)

2. Headphone Chipset

Is similar to a processor in a laptop. It is attached to the motherboard (SMT process) and can have DSP, DAC, AMP and Bluetooth module included. Also depending on the chipset you have possibility to support different codecs. For example Qualcomm chipsets support APTx and it’s variations like HD while some support only AAC and LDAC. Same as with laptops you can choose to have intel integrated graphics or you can go for dedicated graphics card. Having a dedicated graphics card allows you to achieve substantially better graphical performance as it’s the only job of GPU. Same with headphone chipset. You can get an ok performance by using integrated DAC, AMP, DSP but having them dedicated allows for a substantially better performance. Main trade offs are size, extra cost and power consumption (thankfully there is no heat decipation issues in headphones :D).

3. AMP


This picture shows the idea of how amp works amplifying small current coming directly from the mic to output larger one to produce sound

A headphone amp is a relatively low-powered amplifier that raises the low-voltage audio signal from a source device (be it a turntable, PC, or smartphone) to a sufficient level such that it can be converted into sound waves by the speakers inside your headphones. It works like the amps used to power full-sized speakers but operates at a lower scale. Good amp ensures that amplified current is clean and stable.

4. DAC

image

DAC - Digital to Analog Converter converts digital 0s and 1s in which the song is stored to analog signal. Afterwards it sends that analog signal to an amplifier. When you hear digital recordings, you’re actually listening to an Analog signal that was converted from digital by a DAC.

5. DSP

DSP stands for digital signal processing. In general DSP is capable of

  • Generating wider frequency output
  • Filtering out any reverberation
  • Gain control
  • Real-time channel mixing

Most importantly in our case DSP affect the Noise Cancelling performance. Currently the best noise cancellation DSPs are used by BOSE and SONY. Fortunately Sony’s latest gen DSP is available in the market and will alows us to have top notch noise cancelling

Ok so let’s first recap the specs so far:

After studying various chipset options we concluded that Qualcomm QCC5124 is a no brainer as it has the best Bluetooth performance in terms of stability in the market, has Bluetooth 5.0 allowing for at least 2x battery life and supports APTxHD, ACC and LDAC(if we decide to use it).

As for the noise cancellation and audio quality we had 2 options:

  • To go with an all in one solution, so to use QCC5124 chipset from Qualcomm that has integrated DAC, AMP and DSP
  • USE QCC514 for Bluetooth 5.0, APTX HD and other codecs while using dedicated AMP, DAC and DSP.

While QCC5124 is considered to be a flagship chip nowadays after testing it we think it’s not yet there when it comes to noise canceling and audio quality so we decided to go with the second option as having separate modules to handle different tasks will substantially improve individual performance of headphones.

Is there any downside of using the second option? Increased cost in few dollars per unit is the only real disadvantage but we think that the result is well worth it!

Noise cancelling:

We are planning to use DSP from Sony WH1000MX3 model for the noise cancellation and we will be testing various options for DAC and AMP

Muse Drivers

Now a bit more about the driver we use. Grandsun, our manufacturer, has been developing it for past 7 years and I have to say that all their research paid off! As mentioned, the beautiful thing about this driver is that it allows to reproduce music more clearly and with noticeably less distortion (THD) especially at louder music levels then with normal dynamic driver. Driver we selected allows you to enjoy your favorite songs at a new depth level and hear much more finer details. So how does it differ from normal driver?

Normal Dynamic Driver

Headphone-Zone-Dynamic-Driver-Unit

Driver we will use (manufacturer calls it ironless but we need to come up with a better name :slight_smile: )

The main difference between two drivers is how the magnetic current moves. In a normal dynamic driver magnet and voice coil have their own magnetic fields that FIGHT with each other causing extra vibration in diaphragm resulting in higher harmonic distortion. Iron-free driver from GrandSun on the other has 20 strong magnets that align magnetic forces with the voice coil magnetic filed and produce a much cleaner sound. Essentially there is no contact of the normal metal frame part and the diaphragm due to the strong magnetic field.

Now some Questions to you

How important is smart Assistant to you assuming it does not add cost?:

  • I would love to have Google Assistant
  • I would love to have Alexa
  • I don’t care to be honest

0 voters

Based on my explanation did you get the idea of how GrandSun’s driver work?

  • Yes
  • No
  • Other

0 voters

Coming next: Production & Testing of headphones!


Headphone smart assistant test room

19 Likes

I understand that the 3-D printed headphone is a first rough prototype, but is that model going to represent the general silhouette and look of Muse? I have to admit I am not a fan of the look. Maybe it’s because it is made of plastic but I’d rather the rotating hinges connect both sides of the earpiece. Hope you all get what I mean, not great at describing objects tbh.

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I very much agree with @TechieWeirdo on the appearance.
Additionally would like to hear more about mics to be used for noise cancelling. I read that the upcoming Headphones 700 by Bose have 8 mics, which honestly sounds like overkill but I am far from being knowledgeable. I’d be interested in the costs of various mics and what performance (like frequency range, battery drain, size, weight) and costs would result.

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I doubt it will look like that. The picture is just a 3D printed first draft to see what it looks like when they put the components together.

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Hey Folks!

It’s not really indicative of the design but we needed to assemble the simples possible model:) design will be coming in later!

As for the noise canceling it’s not only about the amount of mics but about the DSP. DSP itself has amongst the highest effects on noise canceling performance as it’s responsible for actually providing the cancelation.

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I learn a lot from this kind of reports. Keep it up!

PS: “Ironless drivers” sounds quite cool to me, but you could also call them “HOVERDRIVERS” :grin:

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Venti
Floating Driver
Mag-Lev

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Glad to hear that! In that case I am all for Muse! :slight_smile:

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“Tubular Magnetic” drivers (technical term, the magnets are aligned kinda like a tube or cylinder), “Unifying” drivers (simple, and accurate, they unify the voice coil and the magnet), bedtime now so more to come another time!

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Do you have a ball-park target price for these?

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We decided to go with a similar approach Mercedes used to have for cars back in the day:) We build the best we can and then find out the price. But I am sure we will be competitive:)

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Well, I am satisfied user of WH1000XM3 rn but this sounds great. :slight_smile: And for myself I would suggest implementing LDAC difference (Tidal x Spotify) can be heard even with wireless use case.

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Welcome to the community!

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I would love to know if this chip would support the AptX Low Latency codec. For me personally that would make this the ultimate headphones. I know you sacrifice some quality with the codec, but wireless gaming would be amazing!

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“dissipate” Also the first “it’s” has one apostrophe too many. :stuck_out_tongue:

How do you find the noise cancelling performance of the mics? I intend to use a headset for Skype calls and my current plantronics are excellent for that (but very average for everything else!)

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From the bit of research I’ve done there are very few, if any, does everything headphones out there. By this I mean one set to serve the various use cases:

Music
Video
Bluetooth TV
Gaming
Skype
Phone calls

Would be amazing if Muse could pull it off and be the one size fits all for everything!

1 Like

I’m only interested in music, video and gaming. And it doesn’t have to do all of those at the same ( so switching codec is OK by me). The others are nice to have imo.

Great choice of drivers!
In reviewing the patent plus a scientific paper on the technology (link below), I might call it an “Align Drive” or “LineDrive” acoustic engine because the twin section voice coil also aligns the voicecoil on axially throughout it’s travel, somewhat like a 4 link rear end keeps your axle at right angle to the drive line.
This scientific paper is phenominal in explaining the driver technology;
https://tel.archives-ouvertes.fr/tel-01279478/document

Clear Audio has also chosen the GranSun driver for their new headphone.
($280US, 20hr bat, w/built in mic for phone etc.)
https://cleeraudio.com/product/flow-wireless-hybrid-noise-cancelling-headphone/

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Thanks for this post, btw. Very interesting!