Knowles acoustics just launched a new dual driver, the GM-34020. Is it worth looking into? Lets have a look. I got a pair in just recently and below is my summary. First dimensions: in below two images you see from left to right three different two driver modules: a rather old Sonion dual...

If you can communicate with the service supplier, ask them to adhere to the proper post printing procedures (washing and UV curing). If not done correctly this can lead to discoloration, brittleness of the material. Also any unpolymerized resin (the goo that is poured in the printing vat)...

standard SLA resin 3D printing has good accuracy and may be right for the task you described above. When designing your shell based on the scan take the design guidelines into account and ideally get with the service supplier in contact upfront to avoid unecessary iteratitions due to failed...

Hi all, I recently got a sample of Bellsing 260C90021 (short BRC260 hereafter) which are kinda like clones of the well known dual driver module Knowles GQ-30783-000 and I thought it would be interesting to make a direct comprison. I subsequently performed a number of side-by-side tests in...

I am ordering some BAs from Sonion rep in Europe. Anyone interested to hop on? PM me if interested. Costs will be sum of {share of shipment to me, shipment from me to you and the actual price of your order}.

Thanks! I'll try that....

where were the input cables attached on the crossover? Can you provide a better closeup of the crossover?

can anyone advise how to accurately measure a BA driver impedance (circuit setup, measurement instruments etc?)

You have a point there MuZo2, Indeed there is a steep learning curve and investment associated with 3D printing headphones. It took me roughly a year of serious hobby time and quite some money to advance my "home made IEM" project to a 3D printed, ergonomic universal shell, dual BA driver...

Yep. Its been long in the making (the progress bar has been in the upper percentages since a while. Driver implementation though will require some skill given that the required transformer (ca 400V) will have to be accomodated (safely) in the shell along with the driver. Quite a lot of space...

looks pretty cool, but careful, the devils are in the details -> i could not readily find many reviews on this, I would wait on for more experience with this machine. -> max resolution and printing speed may only be applicable under certain circumstance -> small form factor will mean a small...

I have some spare original Estron XT-ESW litz wires (2 cm, pretinned, red) for sale. PM me if interested.

Hi all, I have several IEMs (2 pin termination) and look for a replacement cable with a proper inline microphone. There are a lot of cables around, cheap, not so cheap and ridiculously expensive. I am particularly interested experiences with durable good quality cables and microphones with...

I am planning on painting/ varnishing my IEMs with different colours. Anyone's got a hint which type of colours to use? I am particularly interested in proven skin friendly materials and where to get them. Thanks Philipp

Hi all, I am into my first DIY IEM project using Knowles BA drivers and need to glue shell pieces together. Knowles advises that some glues are not compatible with their drivers since components of outgassing can diffuse into drivers and damage them permanently. My inquiry at Knowles which glues...

very nice. where did you get those sockets? they look cool.

hi all, does anyone know a source for lead-free, preferably RoHs compliant bulk headphone cable that is already braided?

Fully agreed

Morgen Chris, try a slightly smaller tube diameter (maybe 1.4 -1.5 mm) as alternatice and some different lengths. If you dont get the desired frequency response, I would recommend to use separate tubes.

Hi Einencool lower frequency response measurements accuracy / precision and repeatability will also depend on the volume of the cavity of your coupler. Take care that your measurment setup is reproducible and that the cavity volume is not too large. low frequency response will also vary with...

thanks all for the hints and links. Maybe I should rephrase the question and ask for a range of impedance rather than specific values?

I'd be interested to get a list of output impedance values for DAPs and mobile phones. Can anyone give me a hint where to look?

I tried to set up something like this a while ago and did not succeed. To succeed you need to define the objective and audience of such documents and you will need a team of committed people with good coordination and with a sufficient amount of expertise in many areas which commit time and...

I will be into a small 1 or two driver project soon and need your advice on which sound measurements (like frequency response) you consider most important for development?

First I would test the entire electrical connection from sound source to driver. Have you soldered both ED-29689 correctly (correct solder pads (not the middle one...), same polarity etc?). Have you followed knowles soldering instructions (see...