Looking to up the SPL's of my factory system a few DB, and debating two options:
1. Powered head unit (~20W RMS x 4) with a mono (or bridged 2 ch.) amp for the sub (~80W x 1). Total system cost ~ $700.
2. Head unit pre-amp outs to 5-channel amp (Alpine PDX-5: 75W x 4 + 300W x 1). Total system cost ~ $1400.
I am not a teenager looking to damage my hearing (already did that 20 years ago), but do want a system with enough poop to hear over the wind noise when driving with the windows down. I'm guessing the powered head unit will be sufficient, but looking for opinions from folks who've gone both ways.
Cost is not much of an issue / just not interested in spending money for SPL's I'll never use. I listen mostly to rock / no bass-thumping hip-hop. Thanks.
dodge05ram:Looking to up the SPL's of my factory system a few DB
"A few" [3] dB increase equates to double the output...
A few questions/comments before we get in to any recommendations here:
02 BMW 330Ci, Alpine DVI-9965, Alpine MRA F350 5ch, Alpine MRP T220 + 2x Kicker 6x9 FreeAir, Kicker KX1200.1 + Alpine 12" Type-R, 2-Way Security, Keyless Entry, Remote Start
Normally what happens is someone will buy a 500 watt sub, and then decide their other speakers can't keep up. They get new speakers and amplify them, and decide that 500 watts isn't enough bass for their loud mids and highs. It becomes a struggle to keep the highs, mids, and bass on an even keel. For someone who wants a balanced stereo, i recommend using a sub that is twice the power of the front speakers. Either way you go, you've got the right recipe.
75 watts is a considerable amount of power for regular speakers, and it's really not so important to amplify the rears. Maybe consider a less expensive 4 channel amp, and just amplify the front speakers and a sub. Having a 4 channel offers flexibility for future upgrades. It's a compromise that would allow you to purchase a dedicated sub amp down the road if the power wasn't enough . This one gets recommended by many ppl on the forum, and has the highest customer ratings on the CF site.
Thanks for the replies, guys. I should have mentioned, I design amplifiers for a living / understand well the relationship between power, sensitivity, and SPL, and dB / watts. However, I haven't done much work in the realm of car audio, so I don't have much feel for what SPL I'd get out of a particular power level in a car audio system.
One thought I had today was to just measure the RMS power of my stock system (4 ohm termination and an RMS voltmeter), and just aim to quadruple that. I'd have to pop a door panel and extract a speaker to make the connection, but that may be worth the effort.
To answer Ninja's questions:
1. If I stick with a powered head unit, I'd probably try it out first with my stock speakers. I suspect most stock speakers should handle the ~20W RMS output of a powered head unit. If I go with a 5-channel amp, then I'd plan replace the factory speakers. That was figured into the $700 / $1400 pricing given.
2. I had actually debated this. Shopping 5-channel amps, I noticed they all followed the same trend: sub power = sum of mains power. In other words, the 4 x 50W amps all had 200W to the sub, and the 4 x 75W amps all had 300W to the sub. Knowing subs usually have lower sensitivity, I had expected the power levels on the sub to be a little higher.
3. Definitely interested in sound quality, but within realistic expectations. A Dodge Ram, filled with more plastic than a Fisher Price factory, is hardly an acoustically optimized environment. If I get an amp with decent SNR and I'm not driving my speakers to distortion, I think I'll be pretty happy. I'm not interested in getting into acoustic imaging with individual component speakers, etc.
J Ro: I like your idea of going the 4-channel route, and had not considered that option. I could run the rear door speakers off the powered HU, and use the amp to drive the front doors and sub. If I later find I want to take it to the next level, I could get a separate amp for the sub and use the 4 ch. amp to drive the four doors. Perhaps not a bad compromise?
dodge05ram: I like your idea of going the 4-channel route, and had not considered that option. I could run the rear door speakers off the powered HU, and use the amp to drive the front doors and sub. If I later find I want to take it to the next level, I could get a separate amp for the sub and use the 4 ch. amp to drive the four doors. Perhaps not a bad compromise?
I like your idea of going the 4-channel route, and had not considered that option. I could run the rear door speakers off the powered HU, and use the amp to drive the front doors and sub. If I later find I want to take it to the next level, I could get a separate amp for the sub and use the 4 ch. amp to drive the four doors. Perhaps not a bad compromise?
Precisely. Compromise seems like what you're after. The difference between a 600 watt amp and HU power is so vast, i figured you might want to try something more in the middle, at least at first. No need to blow eardrums, but amplified speakers will sound better.
dodge05ram:1. If I stick with a powered head unit, I'd probably try it out first with my stock speakers. I suspect most stock speakers should handle the ~20W RMS output of a powered head unit.
In my 2002 Focus, the stock HU was probably around 8-10W RMS, the stock speakers are 25W PEAK. They will "handle" the 17Wx4 RMS of the Sony HU, but they distort before I turn it all the way up, and it's plenty loud with the windows up, but not really with them down.
Not a fan of 5-channel amps, but with 4-channels, it likely goes like this:
60Wx4@4-ohms
90Wx4@2-ohms
180Wx2@4-ohms bridged.
I like J Ro's idea of amping the fronts and running the sub off the rears also.
Hope This Helps!!!
2002 Ford Focus Sony CDX-GT410u Sony XT-100HD HD Tuner Stock speakers, no amp, no subs