Installed my Helix about a year ago and finally got around to programming it - bought a dongle on ebay because I could not get one from any dealership barring some sort of...."favor"...probably. Anyway, programmed to 57. I should probably preface this with stating that almost all of my music files come from hi-res 24/96+ FLAC or DSD and I convert them down to the maximum quality the car will play. I do have some 16/44 FLAC files and a few 320 Kbps MP3s in there as well. Sound quality does very much depend on the source file and more importantly the mastering of that song. I do consider myself an audiophile, just not so much for car audio any longer.
All of my listening is inside where I have spent way, way too much money on headphones, DACs, amps, tubes, etc... lol
Before Programming:
- Timing. You could hear each speaker individually. It didn't sound bad at all, but basically like a head unit upgrade with stock speakers.
- EQ settings. I reset it before I flashed code 57, but before, my bass knob was maxed out, mids were at 75% and treble was at 45%.
- Muddy and weak bass, not tight at all, but can be boomy if the right frequency hits. Had to move the bass dial all the way up for the bass to be even remotely acceptable.
- Bright! Basically a treble factory - cold and shrill and definitely required me to mess with the EQ to adjust the sound to my liking.
- Mids were very much recessed, and even after an EQ adjustment, they were still recessed. Not warm at all.
- "Quality" and I say this with quotes due to lack of a better term. Certain frequencies seem to be buried and you'll miss some detail of some of the songs you'll play. Whether that be guitar strums or entire background instruments.
After Programming:
- Timing is definitely correct now and you wouldn't necessarily know it unless you've corrected for timing on another vehicle and know what it sounds like.
- Began with flat EQ settings. Huge difference at flat curve. The rest of my listening is relative to a flat EQ on the head unit.
- Bass tightens up quite a lot. Very punchy now, and very much less muddy. Still boomy where it needs to be but very much more controlled. Bass output seemingly increased by 5x with the programming.
- Whereas it was bright, now it is warm and the mids shine through everything. Sure, you can crank up the treble to your hearts content with the EQ. Treble actually sounds as if it's coming from the tweeters now if I were to try to source the sound.
- Like I said, very warm sound now. Midrange frequencies seem to be centered on the infotainment system screen, which is due to the timing correction.
- "Quality". Very much improved, and again, you wouldn't notice it if you didn't know for what you were listening. But in many songs, there are many background instruments that I just couldn't hear before and I knew they were there. Now this isn't perfect by any means and there is great room for improvement here, but for the price and considering these are stock speakers, its a hell of an upgrade.
As for soundstage, I really didn't notice a discernible difference between the two. Generally, before programming, the sound was weak unless I cranked up the volume at least halfway and at that point it was so loud, it was difficult to really figure anything out, except for the fact that I wanted to turn the volume down. After programming, the mids are focused on the infotainment system screen. So maybe a slight reduction in soundstage if you want to call that a reduction - it really isn't though. And finally, as for the distortion people are talking about. I never noticed any before, and haven't noticed any after. I've put the volume to 70% after programming and any louder I fear I will blow the subs and speakers, and my own ears. Like I said, generally before programming, the sound was weak and to get acceptable quality I had to turn the volume upwards of 60% to get decent quality. I hate distortion, so I do everything I can to avoid it, always.
So all in all its a great improvement and absolutely everyone that has a Helix should definitely have it programmed, sooner rather than later. No it isn't a $5000 audio upgrade, but for the $550 I paid total, for everything, it is well-worth the price and a no brainer. It punches well above it's price.