So I’m completely new to streamers

[Dumdum]

I have been looking at fitting an android tablet into my car, but I am toying with a raspberry pi 4 model B 4gb and a 7” touch screen to build into the car instead... I will use a topping d10 as a usb coax bridge and a spare USB port will be plummed into the centre console for usb sticks etc

I also need to run android so I can store tidal downloads on the pi via the app on a decent sized ever present usb stick

by my reckoning that’s screen, usb stick, topping and the spare usb input also making the four the pi has all being used, if I need more I can always add a hub I think also

does my plan sound ok?

I am planning on ordering the base pi, the 7” touchscreen and a 3+a usb power supply to run it in the car also... I have 32gb micro sd cards to host the android setup

 

[direstraitsfan98]

You could just connect your pc to your dac and use your phone or tablet to control spotify remotely

 

[Jmudrick]

You could just connect your pc to your dac and use your phone or tablet to control spotify remotely

6.4 inch screen on the LG40, great internal DAC and micro SD. Less than $150 and you're done. Honestly what OP proposes is workable but why unless it's 7 inches or bust.

 

[Dumdum]

I don’t want a phone, ideally I’d like 10+ inches for a screen, but figured a 7” would be a nice starting point and not too expensive for a try out

I have 2x 10” android devices (Lenovo tab 4 pro and a Samsung galaxy tab a t510) and an iPhone XR, however if I can get something that turns on with charging input and also turns off when charging is switched off (ignition on, ignition off) is ideal, so I would need to root the tablet to get it to do that and it’s a little bit foreign, whereas I figured I’d ask on here about the pi option

I would use my iPhone as it give excellent results with the topping via coax into my dsp

However the class I compete in for my sound quality competitions is budget limited and the pi seems and excellent way to get my self a decent source for less than the tablets which gives me more budget for more important items of kit, the Samsung galaxy tab a is my preferred device to use if I can solve the turning on/off issue

the LG is way too expensive as the budget is based on retail value when the device was new in euros and the Samsung tablet is €230 on the price list, the pi would come in at under €175 as storage isn’t included so I can use usb sticks and as cards free without budget implications and also leads are free to use also

please note it’s specific to tidal as I like the way it’s organised and set out, Spotify isn’t something I’m interested in, and it needs to be android so I can save tidal albums to the device which you can’t on a pc at all

 

[XGEOX]

I've done a lot of this in various vehicles and with many different devices; iPad, iPhone, netbooks, various tablets, ITX, SBC, etc.

However I've recently settled on a simple phone-based setup...

A (custom fitted) QI wireless charging pad sits where the head unit would be. This is angled so I can use the screen and has little rubber nubs to keep the phone in place. No cables need to be plugged in.

The audio and control is handled over Bluetooth with a cheap (<$10) CSR8645 Apt-X lossless module, and an Arduino-like board reads the wheel control presses and translates those into BT audio control commands via the module. A crude hand-soldered circuit board integrates the two devices.

My Android phone is configured to launch AndroidAuto automatically when the BT module is detected, and kill it when disconnected.

I don't have to worry about power control for the phone, because it is always on and I take it with me. I also don't have to pay for another mobile data service.

A compact Pioneer GMD1004 handles amplification, installed behind the charging pad in the head unit cavity.

This is by far the most elegant and practical solution I've come up with after 10+ years of experimentation. Total cost (excluding the phone) was probably under $200.

If you are just looking for a really clean and convenient setup, this (or a variation of) would be my recommendation.

The nice thing about this is that you could easily swap the phone out for a phablet or tablet if you want a larger screen; without pulling the dash apart.

I believe some of the latest Samsung tablet models have QI; but you can also retrofit the feature to other devices with cheap adapters - or just use a cable.

Other approaches have various complications; reliability, complexity, size, inconvenience, cost, poor integration, battery drain, noise, etc.

However the class I compete in for my sound quality competitions is budget limited...

Building something for a competition was not mentioned in your first post, so it is unclear if your priority is something that works well in daily use, or something that has extreme fidelity (or SPL).

Unless you've already upgraded your car's system, the audible difference between sources will be negligible.

The specific BT module I have offers sufficient quality for general use. I'd have to spend a lot of money on other parts of my car's system to get sufficient SQ for the DAC/preamp in the module to be the bottleneck. However I did encounter a few really bad BT modules that sounded awful as well.

I have no experience of competitions so can't advise on that.

Since you mentioned it; the official RPi touch screen is crap and overpriced. I would not recommend it at all.

 

[Dumdum]

It’s a sound quality class, so bt is definitely not an option, my system is definitely able to show the difference between the two, it’s very obvious when level matched between the two when using the topping so it is a requirement as an output device (the coax also sounds far better than the analogue via my helix dsp ultra, so coax is staying, I tried both while level matching to under 0.5db and making sure the frequency response was identical)

the issue with the tablet option is I have to use a hub and this would be built in, so if the tablet is on standby and not charging the hub still takes power as do all the devices attached, I have modified a hub so it has the two 5v lines cut via a dpdt relay to stop current draw to the hub or attached, this makes the situation messy and have more parts than ideal, however this is my current plan before I contemplated the pi option, it also doesn’t support wireless charging being the most basic tablet Samsung make, but again for budget reasons it has to stay or be replaced with something cheaper than 230 euros

It’s not as straight forward a request as it first seems and I knew clarity would be required with my needs and wants down the line

Using my phone isn’t an option as an iPhone XR is 1100+ euros on the price list and my limit is 4K, I do have other potential options I can explore, but wished to get feedback on pi’s which from what xgeox has said is a no go if the screen is awful, oh well back to the drawing board once more

 

[Dumdum]

That’s my hub with power leads extracted and relayed for the 5v power transfer issue

 

[XGEOX]

wished to get feedback on pi’s which from what xgeox has said is a no go if the screen is awful

The official screen is (in my opinion) no good, especially if you are on a tight budget; but there are plenty of other options that are cheaper and/or better... Some mount directly to the Pi via the headers, while others have HDMI and little custom PCB connectors designed specifically for it.

I've struggled to find a really good quality display; there are a few (AM)OLED ones, but they're hugely expensive and apparently have some quality issues.

For power, the simplest option with a Pi would be to buy a pre-built UPS hat, or an automotive-specific hat. These handle power-up and down for you (they connect to GPIO and send the shutdown command), and you can run your hub from that as well, simplifying your setup. There are a number of these available. Cost is circa $15-50. Have a look at MasuberryCircuits. They make something that should be ideal for you; though I've not tried it myself.

 

[XGEOX]

Oh, and the reason I didn't go for the Pi+Hat approach myself was that the boot times were too long, and the screen displayed an ugly boot-up sequence while doing it.

Some if it could be suppressed, but generally boot times are nowhere near as good as an NVME-equipped board.

 

[Dumdum]

So as I have plenty of spare time currently I have installed my android tablet temporarily and plugged it into my dsps usb add on card, I doubt it has a toppings detail levels, but I will back to back them this weekend if my second topping arrives

more questions to follow for android people...

 

[deafenears]

Looks like you have Dolby Atmos set up in your car @Dumdum ...

 

[Dumdum]

Looks like you have Dolby Atmos set up in your car @Dumdum ...

No, just stereo with a two way plus subwoofer for car audio competition, if you are referring to the aiming of the drivers being rather skyward it’s all about balancing reflections from side windows and windscreen and trying to keep left and right as point source as possible, these angles give me a left and right that is just outside the drivers locations (they are 0.8l test enclosures with mfc17 and with a higher than usual crossover to the sub they sound pretty decent, I can’t wait to get the 8l enclosures in for the satori mw16p drivers in and playing to get some nicer more refined midrange and a little bit lower response out of the left and right drivers

 

[XGEOX]

Looks ambitious; really looking forward to seeing the progress.