Advice on bypassing the head unit

[competentfake]

Greetings!

I have a 2007 Camry and want to upgrade the audio system, but I've run into a big problem:  I hate every head unit on the market.

I've DJ'd and run soundboards professionally, and while I don't consider myself an audiophile, I have a good ear for tone, and it bothers me when a track doesn't sound right.  I listen exclusively to digital music from my phone via aux input, and my collection is from a variety of sources, so the bitrate and volume can vary quite a bit from track to track, and I like to be able to adjust EQ settings on the fly to compensate for the varying sound profiles.

Now, it could be said that any music played through a stock head unit will never sound right, and that's fair, but I've replaced the speakers and the overall effect isn't terrible.  I run a mostly flat EQ on my music app with the mids toned down a bit, and can get decent sound by adjusting the standard bass and treble parametric controls.on the head unit and balancing the 'gain' of the phone volume with the head unit 'master volume.

Recently, however, I've encountered two significant challenges.  For one, I upgraded my phone to a Pixel 2 XL, which can only connect to an aux input via a USB-C adapter, thus I have no DAC on my music player, and the knobs on the head unit are starting to fail.

So I set myself to shopping for a new system.  I knew I didn't want a touchscreen interface, because not only are the GUIs on those things invariably clunky and unintuitive to use, messing around with the EQ on one of them is tantamount to texting and driving.  I need to be able to EQ by touch, so I looked at the non-touchscreen models only to find that for some reason, every single high-end head unit I have seen is a LED-infested, flashy box with one huge volume knob and dozens of tiny buttons, and worst of all, even though every single one of them boasts a 10 band digital equalizer, the damn thing is always buried in layer upon layer of menus, and therefore might as well be in the trunk.

Why did they take our tune knob away?  I know it wasn't perfect, and factory car stereo manufacturers never seemed to grasp why midrange control might be important, but it was elegant in its simplicity, and tapping a knob to cycle through options and turning it to adjust them is much more efficient and less distracting than navigating a series of menus with tiny buttons, but I sense that perhaps my views on the subject are in the minority.  On to my problem!

As I looked at all these head units, it occurred to me that i don't need any of this stuff.  I don't need a CD player, I use my smartwatch for playback controls, so I don't need those, I don't need Sirius bloody XM radio, or any radio at all for that matter, so I started looking into simply bypassing the head unit, and promptly fell down a rabbit hole.

A few days and a few thousand browser tabs later, this is what I came up with, and I simply want an expert to tell me whether it's feasible.



I found a lovely preamp with a parametric EQ and a portable DAC.  Just a little fuzzy on whether this is possible, feasible, or advisable, and if not, I'd like to ask if there are any alternatives that let me improve my sound and adjust parametric bass/mid/treble and the master volume WITH KNOBS separately from the head unit.

Many thanks,

~Rob

PS: Also if anyone knows of a head unit with a tune knob, that would work also.  I have not for the life of me been able to find one.

Click to read more...

 

[Jeffdachef 5,000+ posts]

Greetings!

I have a 2007 Camry and want to upgrade the audio system, but I've run into a big problem:  I hate every head unit on the market.

I've DJ'd and run soundboards professionally, and while I don't consider myself an audiophile, I have a good ear for tone, and it bothers me when a track doesn't sound right.  I listen exclusively to digital music from my phone via aux input, and my collection is from a variety of sources, so the bitrate and volume can vary quite a bit from track to track, and I like to be able to adjust EQ settings on the fly to compensate for the varying sound profiles.

Now, it could be said that any music played through a stock head unit will never sound right, and that's fair, but I've replaced the speakers and the overall effect isn't terrible.  I run a mostly flat EQ on my music app with the mids toned down a bit, and can get decent sound by adjusting the standard bass and treble parametric controls.on the head unit and balancing the 'gain' of the phone volume with the head unit 'master volume.

Recently, however, I've encountered two significant challenges.  For one, I upgraded my phone to a Pixel 2 XL, which can only connect to an aux input via a USB-C adapter, thus I have no DAC on my music player, and the knobs on the head unit are starting to fail.

So I set myself to shopping for a new system.  I knew I didn't want a touchscreen interface, because not only are the GUIs on those things invariably clunky and unintuitive to use, messing around with the EQ on one of them is tantamount to texting and driving.  I need to be able to EQ by touch, so I looked at the non-touchscreen models only to find that for some reason, every single high-end head unit I have seen is a LED-infested, flashy box with one huge volume knob and dozens of tiny buttons, and worst of all, even though every single one of them boasts a 10 band digital equalizer, the damn thing is always buried in layer upon layer of menus, and therefore might as well be in the trunk.

Why did they take our tune knob away?  I know it wasn't perfect, and factory car stereo manufacturers never seemed to grasp why midrange control might be important, but it was elegant in its simplicity, and tapping a knob to cycle through options and turning it to adjust them is much more efficient and less distracting than navigating a series of menus with tiny buttons, but I sense that perhaps my views on the subject are in the minority.  On to my problem!

As I looked at all these head units, it occurred to me that i don't need any of this stuff.  I don't need a CD player, I use my smartwatch for playback controls, so I don't need those, I don't need Sirius bloody XM radio, or any radio at all for that matter, so I started looking into simply bypassing the head unit, and promptly fell down a rabbit hole.

A few days and a few thousand browser tabs later, this is what I came up with, and I simply want an expert to tell me whether it's feasible.

View attachment 5226

I found a lovely preamp with a parametric EQ and a portable DAC.  Just a little fuzzy on whether this is possible, feasible, or advisable, and if not, I'd like to ask if there are any alternatives that let me improve my sound and adjust parametric bass/mid/treble and the master volume WITH KNOBS separately from the head unit.

Many thanks,

~Rob

PS: Also if anyone knows of a head unit with a tune knob, that would work also.  I have not for the life of me been able to find one.

First things first... in a stock camry head unit the EQ is graphical not parametric you cant choose Q factors nor frequency of it. its just bass mid and treble.

you are literally going about this completely the wrong way. you cannot use your experience in home audio or DJ pro audio inside a car, there's soo much more sh*t in a car that factors into your total sound quality. 

Your phone to preamp/dac is a horrible idea because AUX is one of the worse forms of getting a good signal in car audio its actually below bluetooth believe it or not since everything is aptx now or higher generation bluetooth the audio is actually pretty lossless. You also want to use the head unit's built in DAC vs your phone's sh*tty dac.  However when you use a pre-amp dac, you have too many things in the signal chain that modifies the signal, your phone's dac, your preamp dac, your head unit's dac. Thats going to cause a lot of distortion and unwanted and unnatural peaks in the frequency response.  In car audio less is more.  Stick to one singular source aka your car's head unit.   The stock head unit is trash because its not even a 16 bit dac and only provides 3-5 watts of power per speaker.  Most proper head units have 24 bit dacs or higher.  

Also a properly done system will literally sound good on any genre without you needing to constantly play with your EQ which indicates a horrible audio setup from the start. The more important factors are acoustical door treatments to turn the door into a proper speaker enclosure.  Proper amounts of power and headroom, active crossover networks to quality mids and highs. Proper phasing and time correction along with proper front stage setup to have a real virtual concert on your dash. You literally can see the whole artist walking around on your dash by sound when a setup is done right.

I'd recommend skipping the head unit and just doing a dayton dsp + bluetooth dongle.  Yes bluetooth why? Because i've done many tests and even a 320 mbps spotify bluetooth stream on the dayton DSP sounds massively better than  a store bought CD with a stock head unit or RCAs from an aftermarket head unit with store bought CDs to the dayton dsp.  AUX is the absolute worst dogsh*t quality of the bunch.   The current bluetooth technology ensures little to no loss and all the sound processing and audio encoding is done on a quality audiophile grade DAC thats in the sound processor. Goes against conventional home and studio audio knowledge but welcome to car audio.

 

[Jeffdachef 5,000+ posts]

this dsp has 6 saved preset slots for you so you can do 6 different tunings and switch between them during your drive if needed. Download the dayton dsp app on the playstore and play around with it. Active crossover networks with bandpass capabilities 20hz to 20khz adjustments, different slopes like butterworth, linkwitz riley, bessel from -6 to -24 db slopes. Time correction. 8 channels of output, 10 band per channel of EQ so you have 10 bands for subwoofer, 10 for midbass, 10 for midrange, 10 for tweeter left and right independant adjustable so around 80 bands of parametric EQ total, Q factor and frequency selection of any frequency for extreme precision tuning.

https://www.parts-express.com/dayton-audio-dsp-408-4x8-dsp-digital-signal-processor-for-home-and-car-audio--230-500?utm_source=google&utm_medium=cpc&utm_campaign=pla&gclid=CjwKCAjwqqrmBRAAEiwAdpDXtHwBHDA-ox5FWBaE47NOT7qVI1k7J-M11CSUDV1f57h9zbNDhO9SuRoCS2kQAvD_BwE

https://www.parts-express.com/dayton-audio-dsp-bt40-bluetooth-data-and-streaming-usb-interface-for-dsp-408--230-502

I hope you just didnt buy whatever speakers and plopped them in with the stock head unit.  sh*t dont work like that lol, most of the times you get the same or worse sound.

 

[Mooncatt]

First things first... in a stock camry head unit the EQ is graphical not parametric you cant choose Q factors nor frequency of it. its just bass mid and treble.

you are literally going about this completely the wrong way. you cannot use your experience in home audio or DJ pro audio inside a car, there's soo much more sh*t in a car that factors into your total sound quality. 

Your phone to preamp/dac is a horrible idea because AUX is one of the worse forms of getting a good signal in car audio its actually below bluetooth believe it or not since everything is aptx now or higher generation bluetooth the audio is actually pretty lossless. You also want to use the head unit's built in DAC vs your phone's sh*tty dac.  However when you use a pre-amp dac, you have too many things in the signal chain that modifies the signal, your phone's dac, your preamp dac, your head unit's dac. Thats going to cause a lot of distortion and unwanted and unnatural peaks in the frequency response.  In car audio less is more.  Stick to one singular source aka your car's head unit.   The stock head unit is trash because its not even a 16 bit dac and only provides 3-5 watts of power per speaker.  Most proper head units have 24 bit dacs or higher.  

Also a properly done system will literally sound good on any genre without you needing to constantly play with your EQ which indicates a horrible audio setup from the start. The more important factors are acoustical door treatments to turn the door into a proper speaker enclosure.  Proper amounts of power and headroom, active crossover networks to quality mids and highs. Proper phasing and time correction along with proper front stage setup to have a real virtual concert on your dash. You literally can see the whole artist walking around on your dash by sound when a setup is done right.

I'd recommend skipping the head unit and just doing a dayton dsp + bluetooth dongle.  Yes bluetooth why? Because i've done many tests and even a 320 mbps spotify bluetooth stream on the dayton DSP sounds massively better than  a store bought CD with a stock head unit or RCAs from an aftermarket head unit with store bought CDs to the dayton dsp.  AUX is the absolute worst dogsh*t quality of the bunch.   The current bluetooth technology ensures little to no loss and all the sound processing and audio encoding is done on a quality audiophile grade DAC thats in the sound processor. Goes against conventional home and studio audio knowledge but welcome to car audio.

I'm mostly in agreement with this. Most music is mastered properly so you hear it as it's intended to sound in a proper listening environment. With a properly tuned car system, the EQ is almost set it and forget it. I use to fiddle with the EQ all the time too, until I took an hour or so one day with some test tones and a meter to set the EQ for a mostly flat response. The difference was night and day, and then only made a couple minor tweaks to adjust to taste and I was done. After that, the only time I changed it to a vocal profile when listening to news/talk. If your music is wildly different between tracks, you may want to consider looking for better recordings that are more true to life.

Where I differ is on the sound stage and use of DAC's. It's personal preference, but I don't want a virtual stage on the dash. I prefer a more immersive sound, closer to what you get when listening to headphones. There is a good reason for not running rear speakers, but it is not a hard and fast rule. Set your system up the way it sounds best to YOU. For the DAC, you only need one. It stands for Digital to Analogue Converter. Once the signal is converted to analogue, any additional DAC serves no purpose. Some phones have good ones built in (notably the LG V-series), and some stand alone USB DACs are better than others. If you decide to connect via Bluetooth or direct USB, then the phone DAC doesn't even come into play and conversion quality is determined by whatever you're connected to.

 

[competentfake]

First things first... in a stock camry head unit the EQ is graphical not parametric you cant choose Q factors nor frequency of it. its just bass mid and treble.

you are literally going about this completely the wrong way. you cannot use your experience in home audio or DJ pro audio inside a car, there's soo much more sh*t in a car that factors into your total sound quality. 

Your phone to preamp/dac is a horrible idea because AUX is one of the worse forms of getting a good signal in car audio its actually below bluetooth believe it or not since everything is aptx now or higher generation bluetooth the audio is actually pretty lossless. You also want to use the head unit's built in DAC vs your phone's sh*tty dac.  However when you use a pre-amp dac, you have too many things in the signal chain that modifies the signal, your phone's dac, your preamp dac, your head unit's dac. Thats going to cause a lot of distortion and unwanted and unnatural peaks in the frequency response.  In car audio less is more.  Stick to one singular source aka your car's head unit.   The stock head unit is trash because its not even a 16 bit dac and only provides 3-5 watts of power per speaker.  Most proper head units have 24 bit dacs or higher.  

Also a properly done system will literally sound good on any genre without you needing to constantly play with your EQ which indicates a horrible audio setup from the start. The more important factors are acoustical door treatments to turn the door into a proper speaker enclosure.  Proper amounts of power and headroom, active crossover networks to quality mids and highs. Proper phasing and time correction along with proper front stage setup to have a real virtual concert on your dash. You literally can see the whole artist walking around on your dash by sound when a setup is done right.

I'd recommend skipping the head unit and just doing a dayton dsp + bluetooth dongle.  Yes bluetooth why? Because i've done many tests and even a 320 mbps spotify bluetooth stream on the dayton DSP sounds massively better than  a store bought CD with a stock head unit or RCAs from an aftermarket head unit with store bought CDs to the dayton dsp.  AUX is the absolute worst dogsh*t quality of the bunch.   The current bluetooth technology ensures little to no loss and all the sound processing and audio encoding is done on a quality audiophile grade DAC thats in the sound processor. Goes against conventional home and studio audio knowledge but welcome to car audio.

That sounds exactly what I'm looking for.  Thanks, and thanks also to the others who responded.

~Rob

 

[Jeffdachef 5,000+ posts]

I'm mostly in agreement with this. Most music is mastered properly so you hear it as it's intended to sound in a proper listening environment. With a properly tuned car system, the EQ is almost set it and forget it. I use to fiddle with the EQ all the time too, until I took an hour or so one day with some test tones and a meter to set the EQ for a mostly flat response. The difference was night and day, and then only made a couple minor tweaks to adjust to taste and I was done. After that, the only time I changed it to a vocal profile when listening to news/talk. If your music is wildly different between tracks, you may want to consider looking for better recordings that are more true to life.

Where I differ is on the sound stage and use of DAC's. It's personal preference, but I don't want a virtual stage on the dash. I prefer a more immersive sound, closer to what you get when listening to headphones. There is a good reason for not running rear speakers, but it is not a hard and fast rule. Set your system up the way it sounds best to YOU. For the DAC, you only need one. It stands for Digital to Analogue Converter. Once the signal is converted to analogue, any additional DAC serves no purpose. Some phones have good ones built in (notably the LG V-series), and some stand alone USB DACs are better than others. If you decide to connect via Bluetooth or direct USB, then the phone DAC doesn't even come into play and conversion quality is determined by whatever you're connected to.

Good headphones actually project a front stage as well in front of you. Very few audiophile headphones can do this too. Most can achieve a wide sound stage or narrow and more intimate stage but the really good ones can achieve 180 degree view to the front and side of you. The soundstage on the dash is how SQ is graded on any competition level regarding sound stage so its an absolute industry standard. You are free to have your personal preferences though but in top level world class cars, everyone thinks otherwise. If you ever tried connected and switching multiple phones in a system via bluetooth, you'd know that they all have their own sound signature and sound different than the other even without any special effects or EQ turned on the phone.  How the phone's software and hardware transmit date through bluetooth varies via phone, some sound weak and some sounds decent and it doesnt even take a well trained ear to hear the difference.  You can even adjust the EQ on some phones and it actually works via bluetooth playback as well so the statement the DAC doesnt affect bluetooth is false in many ways.

 

[Mooncatt]

You can even adjust the EQ on some phones and it actually works via bluetooth playback as well so the statement the DAC doesnt affect bluetooth is false in many ways.

If the sound is being transferred between devices digitally, then there is no conversion to analogue, which is what the DAC does. Other software, like the EQ, handles the changes before reaching the DAC.

Btw, I'm aware of how SQ competitions judge the sound stage, which is why I said it's a personal preference to run rear speakers. I don't plan to enter any competitions with my system.