# another volume question (signal boosters?)



## JPs300 (Mar 23, 2011)

So, my stereo is definitely very loud/clear, but I know it has more in it. Not something I need/want all the time, but at bigger events it would be nice to really crank it up sometimes. 

I've tried a few different phones and mp3 players. My current g'zone phone does as good as any with it, but I've found if I hook it up to a powered source(car head unit, home stereo output, etc) it still has a lot left in it. 

I'm running an alpine v12 4 channel amp, pushing 125x2 RMS to a pair of cadence marine component 6x9's and 250x1(bridged) RMS to a kicker marine 12" sub. The 6x9s are set at roughly 50hz + and the sub from 60hz down. Currently I have the gain set at about 90% on the 6x9's and maybe 85% on the sub. - The gain is a bit of an "issue" in itself, as it makes one notch of volume on most phones a bit of a jump. I'm planning to add an in-line volume control knob signal cord; probably mount it inside the snorkel inlet(3" riser directly in front of me makes easy access and 99% likely to stay dry). That should not only add easy volume control but also help the "jumpyness". 


My question is, how well do the little in-line pre-amp signal boosters work? Something like this:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=360220383998&ssPageName=STRK:MEWAX:IT

I even thought about running a small amp I have laying around as a pre-amp for the rca inputs on the alpine, but I would think that would be more than a bit overkill. - Like I said, it's very loud/clear as is and has good sound quality, just looking for the ability to have it stupid loud on occassion. 

Thanks,
- Jp


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## primetime1267 (Aug 31, 2009)

I wouldn't run that cheap line driver on your Alpine V12.. Personally, you have your amp maxed out with your gains so high. If you want LOUD, you should just go ahead and get a dedicated bass amp for the sub and call it a day. (Bridge the 6x9's for stupid loudness from v12 and get bass amp)
I'm assumming you are running one of the older F-300 series amps. If you are, then this is what the ratings are mostly likely close to: (Alpine's do a tad more than rated)

4 x 50 Wrms per channel Output power per channel - 

Into 4ohm @ 12V DC - 30WRMS 
Into 2ohm @ 12V DC - 20 WRMS 
Bridged power in to 4 ohm - 80WRMS

And you always have to remember that this is at a FULL 12volt and make sure you have proper sized 10gauge wire for ground and power to run this amp as well.


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## whoolieshop (Mar 22, 2011)

I agree there's really no substitution for more power, boosting the input will likely muddy up your output from the amp in the end. If you've got it loud and clear for normal riding / use I would suggest just leaving it alone, or if you really want it stupid loud, add a dedicated mono amp for the subwoofer as previously mentioned and bridge the alpine, you'll likely be able to cut your gains back a bit as well. I don't recommend anything over 75% on the gains but you're likely to get 90% out of the alpine without running into distortion.


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## JPs300 (Mar 23, 2011)

Yes, it's an older alpine, been barried in my spare room for idk how long. I looked it up when I went to use it and found it to be rated 125x4 rms; it's a bigger amp(roughly 12x12x3), not just a little amp like we typically use for wheelers. It's rated with a 25amp fuse. I've got 8g audio(fine strand) power cords running to it directly from the battery, plus a typical switched remote cord. 


I'll probably just let it be as is. Adding another amp to my electrical system isn't likely a wise idea. - I will say the amp and speakers have been great. *Very* clear even at max volume with the rather high gain setting. I may tweak on the cross-over a tad, maybe even the gain out @ 90ish % and cut the highs off 10-15hz higher to help them carry the mid range a littler louder. 

Thanks for the input guys!


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## whoolieshop (Mar 22, 2011)

No problem, you could always upgrade your amp to a more powerful 4 channel when/if that one dies!


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## JPs300 (Mar 23, 2011)

That I might just do, but it's not likely to die anytime soon unless I purposely kill it. - Can't justify that when the funds would be better used elsewhere.


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## JPs300 (Mar 23, 2011)

hhmmmmm, my mind got to wandering last night.......that amp is 2ohm stable:saevilw:. - I'm thinking of adding two 6-1/2's on the front corners; obivously bridged in with the 6x9's.


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## JPs300 (Mar 23, 2011)

primetime1267 said:


> I wouldn't run that cheap line driver on your Alpine V12.. Personally, you have your amp maxed out with your gains so high. If you want LOUD, you should just go ahead and get a dedicated bass amp for the sub and call it a day. (Bridge the 6x9's for stupid loudness from v12 and get bass amp)
> I'm assumming you are running one of the older F-300 series amps. If you are, then this is what the ratings are mostly likely close to: (Alpine's do a tad more than rated)
> 
> 4 x 50 Wrms per channel Output power per channel -
> ...


 
just for reference, you are right on these ratings. I had it out to make some adjustments, so I checked the model # again and looked up specs. 

30x4 rms @ 12vdc, 50x4 rms @ 13vdc, 60x4 rms @ 14vdc
Bridged is 80/100/125. 

I bumped the 6x9 cut off up 10hz, switched the input on the sub side to the mono setting(input 3*+*4, instead of ST) and maxed the sub gain. It will crank for all my phone is worth, crystal clear and plenty loud enough. - The sub only really hits good when the volume is maxxed though.


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## whoolieshop (Mar 22, 2011)

If you bridged the 6x9's and not the sub thats probably why they are overpowering the sub now, if you had two subs and bridged them mono they should keep up with the 6x9's


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## JPs300 (Mar 23, 2011)

It's running as a 3 channel, 6x9 on each "front" channel, the sub bridged on the rear, all 4ohm speakers. 

The sub is great at full volume or one notch down, but it's hardly noticable below that. - Fine by me, good sound quality all-around and thumps good when I'm cranking it.



****One thing I did notice on the spec/instruction sheet I found on-line. - I set the input switch as 1+3/2+4, assuming that was the setting for running only one pair of inputs. In actuality, that is "the sum of input 1&3 and the sum of 2&4". Since there are no inputs on 3 or 4, I wonder if that's cutting the volume some? - Guess I should open it back up one more time and switch it to 1-2, as that's what the manual calls for per using only the one set of rca inputs.


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## JPs300 (Mar 23, 2011)

Setting the input switch correctly definitely helped. I can take it up to totally obnoxious now, certain songs will distort it so it seems to be doing all that the speakers can do now. 

Huge difference in the sub with the input switch. It bangs now as a 12" should.


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