My previous thread I mentoned finding a small Alpine AMP, #3505.
I finally dug up some interesting info on it. This model actually came on some high end cars from the factory but I'm sure in different trim and it's 25 watts per channel which is probably good enough for my use, to drive my 4x6's. Now my two low out's are taken one for the sub and one for the 6x9's so my choice would be get a splitter or run off the high inputs.

Heres the stupid question. Since my head unit is "20/25 watts per channel" if I run to the high input to this AMP will it add anything or will it reduce the signal or what??

I understand the wattage from the head unit is just rated at the 25w maximum output so I should be ahead of the game by running this tiny amp. What do you think?

 

well you could wire it in temporarily to see what it is like, but I really dont see you making that big of a differance with it. Most modern HU's have decent amps built in, and seeing as how old that amp is.... I just dont see it making a big differance.

That said, cool find!

 

I think you should still see an improvement. Not in how 'loud' it gets, but how 'full' the sound is. Give it a good before and after listen (just on the front) and I think you get an improvement in the highs and lows, more with the lows, but you're NOT going to hear that with those speakers so concentrate on the highs. DON'T use the high inputs, get a splitter.

 

Ok I'm here at the shop or as I like to call it my birds home.

My head unit is a Pioneer 50x4. So thats 12.5W per channel right? So it should show an improvment by using this amp.

What do you guys think of the passive dividing boxes in the pic? Should I use those peices too since the 4x6's are just for highs?

 

Most headunits can output around 20-25 watts per channel but they do so at 10% THD, which is horrible. Most amps make their rated power at something like .0x% THX. You might not be able to get louder but it will defiantly sound better.

I agree with NEEDAZ - get a splitter.

 

Can't really see it. Is ti just an X-Over? If so you could use is or just grab some 'base-blockers'.

 

A typical modern aftermarket HU will put out about 18-20WRMS when driven full-range at low THD. Given that this Alpine amp was manufactured to OEM standards rather than typical aftermarket standards, I"m sure it won't be much better than your HU.

If u had another set of RCA outputs to use, it would be marginal as to whether or not it would be worth hooking up the amp to gain such a small amount of power. But since u don't, it's definitely not worth it. Using the high-level inputs will more than enough distortion to obliterate any small improvement u might have seen, and using Y-splitters on the RCAs for the 6x9s will weaken the low-level signal and eliminate your ability to fade from front to rear. Overall, any gain u might notice will be very minimal, and there's a good chance it will actually sound worse. Not worth the hassle.

 

What? 18-20WRMS full range and low THD, NO WAY. Try 13W on a good day. I'm not even going into the other part or that paragraph (shoot, i just did).

Now I admit I don't know what he is running for an HU (or other amps), but I would be VARY surprised if two amp would present enough of loading to make any noticeable (or even measurable) difference.

This is a lot of discussion for such a small amp.

 

what if the headunit was similar to the new Pioneers that output 30wrms?

I would just get a much better amp on the cheap...

 

Operative statement. That HU and the high power Alpine HU are NOT typical. They use internal switch mode power supply's that give the HUs internal amp 18Vdc (in the case of the Pioneer), not the normal 13.5Vdc. And even their power output is over rated. Take the new Pioneer DEH-P80, flip the switch from 40W to 60W mode and it's not necessarily any louder at a given volume level, but you notice the extra power the most in the lows, and a lot less distortion with at a higher volume level.

 

This is a lot of talk for a this, just wanted to reinforce that I wouldn't expect any thing big hear. And I think that with those speakers you're going to need to do a careful before and after and even then you'll miss out on most of the improvements.

 

please go to a pawn shop and get a decent 4ch for like $50...


or he could get DVC speakers and wire up the 4ch amp to power up a single pair... then he'd have ample power

 

Wow! That IS the smallest amp ever!

 

yup, even looks smaller than my monsoon amp...