I have been out of car audio professionally for a abut 4 1/2 years now. And even in that amount of time there have been big changes. Eclipse who was a very good company, I started watching fall before I left the shop, and is now gone totally(fujitsu ten company), diamond audio was a great product, but the owner(s) ran it into the ground, we were sending in amps for warranty work and just getting credit on our account for them because they owed so much to vendors that they couldn't get the parts to repair, I believe diamond is still around now maybe they pulled back out of it or changed hands, I'm not sure.
I have been using Memphis car audio or a while now and have great success with them, I have never blown a sub or amp, I still have product from before leaving that is still going strong.
Jl audio is still a great product
Hertz and audison seem to be great as well.
Rockford went down hill a lot.
As far as head units, it's a totally different game now with so much factory deck options and higher quality in them, my old shop is doing a lot of factory deck integration. There are a lot of very high end processors for integration out like the jl clean sweep, audison bit one, and audio control pieces. I had a 2011 Kia sportage which had factory Bluetooth, mp3, USB, aux in, Sirius and steering wheel controls, so I used a Memphis 6ix and kept the deck, first time I have ever kept a factory deck in my vehicle. So with all this being said, there aren't a lot of decent head unit companies left, pioneer, Kenwood and jvc seem to be your best choices, we had a lot of success with jvc in the last few years I was at the shop(years before I would have shot ya for suggesting jvc to me, but times change) there are a lot of low end brands out there still, dual, boss, Jensen etc... But even in a time where decks are a lot cheaper and have tons more features than they used to, you still get what you pay for.
2002 VTX1800C - Muzzys exhaust, Hypercharger, Power Commander, custom paint,
1996 impala SS clone 22" Giovanna gabbs, flow master exhaust, intake, bagged
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