@The_Sko
I've been doing a little more digging and it looks like the way to get the best source signal is to use a HEC-USB module in the V Twelve hooked up the the phone via a USB cable. Then setup the V Twelve to have a source priority of the TOSLINK (assuming it's the input from the UConnect. That way you can have digital hi-res from the phone to the DSP without any conversion and still be able to have audio from the car. How well does the switching work in real world application? No idea. Only downside is you will have to use the Conductor for volume control of the music. I'm planning on doing a similar install with a V Eight (I don't care about the back speakers) and a P One.
@naamanf , been meaning to get back to you (and everyone) on where I landed on the struggle to get the best signal into the system while retaining maximum ease of use.
If you recall I wanted best signal input=best output, WHILE having an easy to use setup that won't break the wife's brain trying to operate.
After a few rounds of going back and forth with my installer and having
Larry Pann, who runs North America distribution at MSC, in-person help tune the truck, and work with me on identifying how to achieve the stated goals above.
His answer was narrowed down to the same thing
@naamanf you stated out of the gate. To get the best out of this system we have to cut out the head unit in the data path. This in turn starts to dig into my ease of use requirement.
His recommendation was to get an
external player like this for example and have it directly play to the amp. This solves a couple of problems.
1. Get the iPhone out of the way since it can't play hi-def music natively.
2. Have multiple sources of audio input in a single hi-def playing device. This includes, but is not limited to, Spotify, Tidal, raw music files and others.
Now, this does introduce a second device where I have to manage music at but for the most part, it's the same set list that I go to on the A&K and just hit download, so not that bad.
The next question is how to get the music out of the A&K device. Two options, wired or wireless. In discussing this for about an hour with Larry, we agreed on this
BT HD module, which plugs directly into the V 12 amp and feeds the P one. This allows the A&K to connect via aptX™ HD audio codec. There was an option of a
USB module which does have a higher bitrate and throughput, but he made a strong argument that I would be unable to tell the difference between the two. He clearly stated that the jump from my iphone (even with
Ztella DAC plugged in) will be night and day, but the next jump from BT 5.0 to USB will be probably unnoticeable and the loss in the convenience of wireless is probably not worth it.
With that all being said I ordered the A&K and the wireless module. Got it all installed, setup, and going. The first few moments of listening weren't wow that's better, it was a HOLY $HIt moment of difference. I tried the same song on iphone, iphone with DAC and then the A&K direct. Everything from the high-end headspace down to the bass response is not even in the same game, to say night and day wouldn't even be fair to say.
For the next test, let's connect the A&K via BT to the head unit and see how that sounds. We did and found it still sounded pretty dang good BUT could immediately tell the bass was not as near responsive, highers were close but not full there. I won't be doing this again, but I should call out that I could control the A&K was able to be navigated via the head unit, which is cool, just unfortunately I don't be doing this moving forward.
Being pleased with how this sounds let's talk about what I lost going this route from a convenience route.
1. In order to switch from the head unit to the A&K as an input on the Helix amp(s) I have to turn the head unit volume down to zero and turn on A&K input. From that moment onward I have to control the volume from the
conductor. This isn't the end of the world but the wife can't turn it up or down now. This also means I have to push the conductor button in once to switch to Sub level control. Whereas prior it defaulted to sub-control.
2. Phone calls - with the input on the amp now controlling what you hear play out of the speakers require that we have to prioritize inputs, so the head unit is the default and anything that comes from it will be played immediately. This includes the phone, parking sensors, voice control for nav, etc.. With a few seconds of delay on the secondary input, once these noises shut down and the A&K is playing it kicks back over to it.
Being wireless allows me to have it charge it (if needed) or I can hand the A&K to the wife and let her go nuts. If we want to play iphone, satellite or any other input it's business as usual. It's just a minor inconvenience to get the A&K rolling. But I think the juice is worth the squeeze in this case.
My final thoughts and I hope I haven't lost all of you by now, is if you want the best this is the requirement to get true full HD sound of the system. I still often play music via the iPhone and even sometimes satellite (yuck) and don't dread it I just know there is something better waiting for it that takes that extra step of taking it out of the truck, download it on the A&K, and bring it back with me. With the add of a 500GB card, I'm pretty endless for the time being on how much I can sync up.
Questions I'm sure, ask away.
. Great build 
