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wonder what fatigue curves on FR4 springs is like
i think fr4 is a lot more glass than matrix

Posted by renesis at 21:41 | permalink | 0 comments


ground beef seems to be 10 similar listings for same grade and weight beef with a whole range of prices
like they catalogged every lb of ground beef in the city
can just imagine kids sprinting through grocery stores
i dont agree because the fibgerglass will just wear and break the solder joint
would trust big giant solder pads w/ non-rohs solder more
tho would be interesting thing to test
right i think itll last a week in a lab, daily use
or at least make the slots like 3x deeper

Posted by renesis at 21:36 | permalink | 0 comments


oh
is it just soldered and flexes along the extended length?
that looks like its going to break in a week
theyre really just mounted with solder?
why are the pads so fucking small
oh well
i dont understand tapingo grocery shopping

Posted by renesis at 21:31 | permalink | 0 comments


yeah
the non-tweez one is just a giant tac switch
i like those a lot actually
button cap is kind of overkill when the button is like 1/4" wide and tall
also theyre assholes if the glued it it looks like its bigger than the hole its mounted on top of
i like their case
american shit = 'case' with completely open sides, two acrylic sheets and 4 standoffs
like why bother
ya
but might feel shit or degrade fast as fuck
looks like it might be okay, tho
boards dont look to cheap, routing is clean
really hard to see how theyre pivoting or flexing, how theyre connected

Posted by renesis at 21:26 | permalink | 0 comments


yeah thats not bad
*it needs
tho typo is also true if a bit popeye sounding
does it have a ball + button for ui?
ha, multi function key, guess not
you think?
like a little stick under rubber bubble?
i think they just mean one button does all the things
i like the tweezers better but for $40 more
oh that shit had a full case
yeah fuck the tweezers

Posted by renesis at 21:21 | permalink | 0 comments


rab: $50 and you have to buy a new cable to do anything with it wtf
or is that for charging
i think theres a battery inside there
shit is kind of ugly from the side
very polite
is the english american or chinese?
i should go to china and write manuals
display looks nice at least
i dont really understand why i needs that much display for this

Posted by renesis at 21:16 | permalink | 0 comments


lots of noise cancelling stuff uses mems
because noise cancelling only owns well in a narrow range
plenty use 1/8" to 1/4" capsules, too
er, only works well is maybe what i meant to say
wonder what the typo is
http://i.imgur.com/e1MJd8J.png

Posted by renesis at 18:11 | permalink | 0 comments


typically the solution is buying a bunch of 1/4" electrets and matching them by hand
why is it better than the $20 usb ones
neat
zzzz_ likes that stuff
mems are great for lots of stuff

Posted by renesis at 18:06 | permalink | 0 comments


big membrane is higher sensitivity so less noise
mems mics arent very high performance, in a measurement mic context
1/2" is typical for low noise, 1/4" is typical for low distortion and wide frequency response
1/4" gets good high frequency response while getting decent noise performance
mems mics are too small for decent noise performance
its just a dimensional issue in relation to wavelengths
mems are cheap and small
it wont be very small
and i think youre making assumptions and the mems mic materials might not be very high performance in terms of weight vs rigidity
you know how i know thats not very good?
because theres a guitar in the pictures and no specs
and it has a pinhole mic
also arrayed mics are not new, theyre just inconvenient
but doing a stargate array with a turntable is a usable concept to build a 3d polar response system
like the RF geeks

Posted by renesis at 18:01 | permalink | 0 comments


anyway, neat chip i hadnt seen that datasheet before
sculptor: theres a non obsolete version
and i think hes just making one
yeah thats never a bad idea
no nothing will ever replace classic mics
if you mean monolithic studio mics
laser mic still needs a diaphragm
sculptor: they might take over for measurement, but thats highly unlikely as well
a microphone is a complete package
its spec depend very much on the housing, besides the actual transducer

Posted by renesis at 17:56 | permalink | 0 comments


usually a bit of tit at the peak, or crossover distortion
check octopart and findchips
actually its likely the headphone jack is right around 0.1%
pretty typical for enduser stuff
yeah obsoleted parts are $$$
maybe consider using the new part with a voltage divider that cuts signal by half
thats why they used to pay me the big bucks

Posted by renesis at 17:48 | permalink | 0 comments


the new one is 0.2% THD+N
which is usable but not very good
slightly under audible distortion
if youre going to make something its probaboly best to use the newer part, unless there is something specific about the old one you like
http://www.analog.com/media/en/technical-documentation/obsolete-data-sheets/SSM2165.PDF
well, either one youre going to need a fixed attenuator to deal with 12v
but right you dont want to attenuate any more than you have to, for better noise performance
anyway, its got the same THD specs
0.2% typical, but 0.5% max which is the edge of audible for typical people
people who do a lot of audio measurement can hear down to 0.1% sometimes
yeah its probably good enough for that
above 1% is pretty shit
its visible on a scope

Posted by renesis at 17:43 | permalink | 0 comments


https://www.sweetwater.com/store/detail/MDX2600
thats a typical studio compressor, cheap one
i guess my point is, getting compressors to work usually requires a bit of tweaking for a specific situation
something simple might work without so much tweaking, but maybe doesnt work at all for what youre doing
http://www.analog.com/en/products/audio-video/audio-amplifiers/micpre-amp-audio-products/ssm2167.html
AD says use this the one you said is obsoleted
but i mean if you can get a dev board with the old part its probably fine

Posted by renesis at 17:38 | permalink | 0 comments


they will usually use jfets or some sort of isolated variable resistor, like an opto coupled light sensitive resistor, to provide the gain adjustment
thats fine
sorry if i seem like an asshole, im having sleeping issues
shrug, you dunno yet
everyone in here was stupid at some point
kevtris excuse was probably that he was 3 years old
even a genius 3 year old is pretty dumb
https://www.sweetwater.com/store/detail/CL9ped
that might work

Posted by renesis at 17:33 | permalink | 0 comments


a potentiometer will allow you more precise control of attenuation, at the cost of known attenuation
you can check potentiometer attenuation with a known amplitude reference
a compressor is used to automatically trim or limit levels to prevent clipping or otherwise overdriving systems or ears
theyre likely going to be dsp solutions
i dont know of any fixed compressor ICs
i know of DSP controller IC that can easily be setup to act as compressor, as well as several other audio devices
analog devices sigma DSP systems are an example of this but maybe more expensive to but a dev board or build one up than just buying a compressor
you can make a compressor circuit out of some opamps
analog compressors arent trivial really

Posted by renesis at 17:28 | permalink | 0 comments


you can attenuate with a potentiometer, which is one knob, manually
or you can attenuate with a compressor/limiter, which is going to be like 4 knobs, or less knobs but more switches, or less knobs with less control
thats fine
seems like a lot of work, but if you need the fixed ratios, thats the way to do it
you can use dipswitches too
doing it automatically is called a compressor
the typical parameters are compression threshold level, above which it will reduce the gain
how much it will reduce the gain depends on the compression ratio and knee, which define the curve of gain reduction vs level
how sensitive it is to changes in average level is controlled by the attack and release times
compression is absically automatic trim
compressor with very fast attack and release times is called a limiter, it can response in the time of a single cycle
it really depends what you want to do
if you need to know the exact input level, switched attenuator (resistive voltage dividers) is the most professional solution
you can use rotary switches, dip switches, relays

Posted by renesis at 17:23 | permalink | 0 comments


what do you mean by automatically
you probably want an attenuator and a compressor
how do you reduce 2v to 0.3v and also 12v to 0.3
so you mean 0.3v and 0.05v?
because then you just need some resistors
if you mean keeping the max output at 0.3v with different input levels between 2v and 12v, you need a compressor
and then youll have to set thresholds level, attack and release times, and compression gain ratio
or
just use a knob

Posted by renesis at 17:18 | permalink | 0 comments


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