Two 9V batteries and four op-amps for a low-current output buffer seems like overkill. does anyone know about a better way to go about it?
Do I really need to get out the soldering-iron again?
131–140 of 429 posts
Re: Do I really need to get out the soldering-iron again?
#132Is this actually a bug in Android (confirmed by someone else on a different phone) or is it a bug in the implementation by this OEM? I haven't experienced it but I also do not use this writer's particular sound files. I think the underlying point is very important. It does seem like quality has been sacrificed in many products to shave a few pennies off the BOM. Why should today's portable CD players be substantially…
They are not shaving BOM pennies, they are shaving NRE pennies. The components to produce good audio are dirt cheap, even for a consumer product, even in quantity. Keeping digital noise out of analog circuits, however, takes effort. Getting the software to not drop step functions at inopportune moments takes even more effort. They won't do these things unless they feel they have to.
Re: Do I really need to get out the soldering-iron again?
#133Earlier quoted context omitted.
You can run the play store just fine on lineageos, which has modifications and isn't official. https://www.google.com/android/uncertified/ just need to register here as of earlier this year apparently
Apparently Play Store is unaffected, but some other apps - banking, streaming, even Pokemon Go - will break. And your warranty (including hardware) is voided. So I stand corrected, and thank you, but I don't think the correction affects the main point.
They work. You just need to install additional software. Magisk + safetynet fix.
Re: Do I really need to get out the soldering-iron again?
#134Is this actually a bug in Android (confirmed by someone else on a different phone) or is it a bug in the implementation by this OEM? I haven't experienced it but I also do not use this writer's particular sound files. I think the underlying point is very important. It does seem like quality has been sacrificed in many products to shave a few pennies off the BOM. Why should today's portable CD players be substantially…
They are not shaving BOM pennies, they are shaving NRE pennies. The components to produce good audio are dirt cheap, even for a consumer product, even in quantity. Keeping digital noise out of analog circuits, however, takes effort. Getting the software to not drop step functions at inopportune moments takes even more effort. They won't do these things unless they feel they have to.
NRE == Non-recurring engineering costs, in other words, stuff like R&D. This was my first encounter with that term.
Re: Do I really need to get out the soldering-iron again?
#135I’ll happily pay the “apple tax” so I can live my life and not have to deal with all the bullshit you did just to listen to some music. Good lord. I’d rather experience the world then mess around with the tech that’s supposed to be helping me live better.
It’s amusing to still hear “Apple tax” in 2018, as if there is no additional value in better hardware, software and support for many people’s use cases.
> It’s amusing to still hear “Apple tax” in 2018, as if there is no additional value in better hardware, software and support for many people’s use cases.
Being a golden cage, I would not argue that it is better software.
Re: Do I really need to get out the soldering-iron again?
#136Earlier quoted context omitted.
That's such a straw-man it hurts. You're concluding, from the fact that a user has found one obscure bug, that android is a broken mess that only Arch Linux types should dare mess with, while Apple products are bastions of stability. The reality is that Apple products are (it appears) no more bug-free than the rest. Have you tried testing this very same thing on an iPhone? Maybe it even has the same bug!
The above comment is reacting directly to a quote in the article, not jumping to any new conclusions. “If anyone reads this post I'm sure loads of people will tell me that my problems are all my own making and if only I invested in an iPhone all my problems would go away. Well you know what? APPLE IS A SYMBOL OF PRETENTIOUSNESS AND IGNORANCE - YOU DO NOT EVEN KNOW HOW YOUR PHONE WORKS - I DO NOT HAVE TO PAY A TAX TO…
This quoted section evoked in me, “that’s right; I don’t have to know how my iPhone works just to listen to some music...”
Re: Do I really need to get out the soldering-iron again?
#137Could’ve spent $199 on an iPod, have high quality audio, load your own music, no “apple tax”. Coincidentally I was looking for something like an ipod shuffle this week and it’s become almost impossible to find, beyond some cheap thrift-store MP3 players.
There's actually quite a bunch of less than $199 solutions (and also not requiring a soldering iron) the OP could also have used to achieve a good experience listening to music.
One solution would have been to just buy that 15 year old hardware he talks about, a lot of older digital music players still just work, I have a bunch of them. Or an external soundcard for a laptop. Or stream music from phone to a Raspberry Pi with a DAC. Or a portable CD player which doesn't hiss.
Re: Do I really need to get out the soldering-iron again?
#138Why does it use two opamps for the ground signal?
Since you have two channels that source current (L and R) it makes sense to have two parallel op-amps for the GND pin to have the same slew rate & maximum current, as both L and R channels return current through the GND line (I would assume).
I am curious as to why it needs any circuitry on the ground line - would a direct connection not work? (I guess I am assuming that L, R and ground are the only connections made to the headphones.) Do the amplifiers put a DC bias on the L and R outputs that needs to be matched on the ground, and if so, would a capacitor in series with the L and R outputs not be enough to isolate it?
Re: Do I really need to get out the soldering-iron again?
#139Pro tip: There are enough PCB shops now that small designs like this can just be done in free EDA software in minutes, 10 boards in your hand with a stencil 9 real days later for less than $50 shipped. The stencil lets you paste the board all at once, you place parts and hit it with a heat gun until everything sets. For audio stuff you get the advantage of keeping everything nice and tight with lower noise. I barely…
Any recommendations for the US? All the circuits I’ve ever made were breadboarded, this could be a fun direction to take.
China is the 9 day shipping component. I use JLCPCB most and SeedStudio because depending on the features each has their own pricing benefit. If you are comfortable with a paste syringe and the component count is small you can skip the stencil and order multiple projects at the same time to seriously save on shipping. Youtube has great videos on stencil pasting and reflow soldering with a heat gun. If you aren't familiar with EDA software you can start at Fritzing or EasyEda and move on to Kicad. Altium is the standard at big businesses.
Here is an example of an MCU based tilt sensor I made earlier this year. I have about 12 hours total into it including inception/design/layout/soldering. It would have taken me 12 hours to breadboard it with components I couldn't use in production. I do this a lot so my process is rather streamlined. I made about 25 boards this year, mostly small test circuits. https://imgur.com/a/XJxp0tO
Re: Do I really need to get out the soldering-iron again?
#140I'm super curious… a. What in these files triggers the explosion of noise (and whether other people have run into this or the author would mind sharing a representative problem file). b. Whether an output attenuator (or "resistor") would work to quiet the noise (edit: the hiss, not the explosion) without a powered circuit.
Hi, author here, I can't send you a sample because of copyright but get "scare force one" by Lordi on CD and rip it into any format.