I need some help with my sound system. Nowadays I have a simple config:
- HU Clarion NX702
- Pioneer GM-X904 Class A Amplifier:
150W x 2 (@14.4V, 4 ohms)
75W x 4 (@14.4V, 2 ohms)
120W x 2 (@12V, 4 ohms)
60W x 4 (@12V, 2 ohms)
- Front Doors
2-way Infinity Kappa 60.11cs
Power Handling (Continuous/Peak): 90W / 270W
Impedance: 2 ohms
- Rear Doors
Stock Speakers connected to the HU (turned on only when there is someone in the back seat; most part of time are turned off)
- Subwoofer Rockford Fosgate (R1-1X10) (10")
200W RMS; 4 ohms
I've already read a lot about how to config gain in amplifiers, but I still have some doubts:
1) I see many people saying to match HU Preout with Amplifier gain. In this case, I should set 2V in my amplifier (its the minimum setting in my amplifier), since my HU Preout is 4V. If I do that, I don't have a good output from 2-way (rear stock speakers become much more louder than 2-way speakers) neither from Subwoofer. However, If I turn the amplifier gain up that feeds 2-way speakers (i.e to 1V), I can hear a hiss sound from 2-way at low volume and good sound level at high volume; HU level goes from 0 to 40 and I have an excellent output in 30 with 1V amplifier gain feeding 2-way speakers.
2) Bass is very weak even with armrest down (enclosure is positioned aligned with back seats with Sub facing rear car). I know Sedan trunks has much less SPL than hatchback (I've used this amplifier in a hatchback car - few years ago - and the bass was incredible good). I've tried turning amplifier gain at maximum (0.4V); even so, I don't have a great bass. I don't know if this setting can burn my Sub, but I don't realize any distortion at maximum amplifier gain level configured only for Subwoofer (2-way is feeded with 1V amplifier gain to have a good sound level, despite hiss sound at low volume)
I ask if I can have some problems with my sub and 2-way speakers, since I always see people saying to match amplifier Gain with HU Preout.
Is adding a second mono amplifier the only way to improve bass? I see many people from BMW forum complaining about lack of bass even with 12" Subwoofer and 500W Mono Amplifier. Then I don't want to spend more $$ if there is a risk to have a bad result.
Will I burn my Sub if I let amplifier gain at maximum (0.4V)? At maximum setting on sub channel I think bass is starting to be good and I can deal with that only if there is no risk to my Sub. I don't know why my Sub is not distortioning at maximum gain Amplifier setting (maybe my HU Preout is delivering only 0.5V @ 30 HU volume level...what do you think?)
I'll be waiting for your comments ;-)
PS: Sorry for my bad english