Suggestions for a 2 ch speaker level input amp

I have a 2021 SR and I tried rerouting the rear door speaker wires to a diy speaker box with better speakers. It seems there's not much output to the rear door speakers.
I'm not looking for competition or audiophile level upgrades. Just looking for a small 2 channel amp that I can plug the rear door speaker wires into and get a little more output to the rear. Something decent quality and relatively inexpensive.
Heck, if there's a small amp that would power a small sub and left/right tweeters, that might be even better. Not sure if they make something like that. Maybe a 4 channel that I could run tweeters from 2 channels and bridge the other 2 for a sub? No idea.
Any recommendations appreciated.

 

This seems like it might do the trick for the money. Anyone know if this Boss name is Junk? Same name that makes guitar pedals?

$105 BOSS Audio Systems R2504 Riot Series Car Audio Stereo Subwoofer Amplifier - 1000 High Output, 4 Channel, Class A/B, 2/4 Ohm, High/Low Level Inputs, High/Low Pass Crossover, Bridgeable, Full Range

https://www.amazon.com/BOSS-Audio-R2504-Bridgeable-Amplifier/dp/B004S52OL6?th=1

 

Boss is pretty low-end stuff, and has been for years.

I think you are on the right track with a 4 channel and bridge 2 for the sub.

This one looks nice and compact with speaker-level inputs.

Kenwood KAC-M1814 Compact 4-channel amplifier — 45 watts RMS x 4 at Crutchfield





This one got good reviews, a little more expensive, but a little more wattage as well.

Clarion XC2410 Compact 4-channel amplifier — 50 watts RMS x 4 at Crutchfield

 

that looks promising

 

I know this is probably all junk compared to some of the high$$$ builds out there, but I have to imagine this will be an improvement over the stock rear door speakers being pushed by the stock HU. And that's all I'm really going for is just a little bump over the stock setup. I'm actually happy with the HU and front door speakers.
The Boss stuff is likely low end, but I really like the way it's configured with the built-in crossovers and I REALLY like the subtotal for this stuff.
I removed the rear seats and center front seat. I have a diy console/storage that runs from between the front seats to the back wall. This stuff should all fit in the center console toward the back and I'll use the 4" 2ways for mids/highs and just have them mounted in a box, in the center of the back wall, firing forward, down the middle. I don't have the truck at the moment, so I can finish the console while I wait for it.
I would've waited for more input, but I'm too impatient and impulsive.

 

How much of a difference is there in using a single VC sub, bridged, vs a DVC wired to 2 channels?

 

Well, I had some points, or cash back, or whatever they call it.
I got the stuff above for $41.
If I get the results I'm looking for, awesome.
If any of it is junk, I can return it. If I can't, I'm out $41.
Hopefully I don't catch the car audio bug and get stupid with this stuff.

 

Yeah,.....sooooo,....
I have 2 input channels (rear door speaker wires) and just bought a 4 channel amp. Derp.
I had a great idea of using channel 1-2 with the high pass filter and the 4" 2-ways, then channel 3-4 with the low pass filter, bridged to the sub. I just didn't bother to think about the fact that I need 4 inputs.
I'm wondering if I can run the 2 input wires to all 4 inputs. I looked all over online and couldn't find anything. I found one response somewhere that said if using low level RCA inputs, to use input 3-4 and switch the amp to 4 channel. But that was probably specific to whatever amp they were discussing. I don't have a switch to choose 2 or 4 channel. Plus, I'm using the high level inputs.
Anyone know if it will be an issue to split the input wires and run them to all 4 input channels?

 

Boss and Pyle are bottom of the barrel, IMO. You've got it so might as well try it... but for a little more you can get a much better setup. Again, my opinion.

A couple things... DVC subs are used mostly for wiring flexibility these days. Back in the day before virtually every amplifier was bridgeable, had built in crossovers, and 100 watts RMS was a good amount of power that also cost a good amount, DVC's could be run off of two amplifier channels to increase the amount of power sent to a single woofer. They were also used as center channels; basically wire a left channel to one coil and a right channel to the other and if the signal was equal from both channels (meaning the sound is centered on the recording soundstage) the speaker plays loudly. If the signal is opposite on both channels, the coils actually fight each other and the speaker doesn't play.

Anyways, these days, watts are cheap especially with modern switching power supply 'digital' amplifiers (in short, digital amps are much more efficient - 80-90% vs 30% efficient of old class A/B amps - but basically have a hard limit for power; if it makes 300 watts RMS, at 301 watts RMS the distortion starts to increase exponentially, whereas an A/B amp with a good power supply and circuit design can take advantage of higher input voltage and put out way more power than it is rated for with moderately increasing distortion). Also, digital amps are usually better regulated so low impedance loads aren't an issue (A/B amps running low impedance loads have a tendency to burn out - sometimes literally...).

Subwoofer output won't be any different for a single voice coil sub on a single bridged channel vs a DVC sub running off of two channels as long as they are fed the same power. However, there is a one big caveat: tuning two channels to get identical voltage/power output from each channel to send to a DVC sub is somewhat difficult. It's even more difficult with a cheap amp as they output of each channel can vary quite a bit. Perhaps that is surprising, perhaps not, but an amplifier takes what is typically a 4v max voltage signal and bumps it up 10x, 20x, even 30x. This means that a small variance in a circuit path due to cheaper, higher tolerance components can make for a huge difference on the output side. So it is generally recommended to run two channels bridged instead of two separate channels to a DVC, even if running a DVC sub. Just select the subwoofer for the correct final impedance. For example, a DVC 4 ohm sub will wire down to 2 ohms to extract more power from an amplifier,, or up to 8 ohms for better damping factor but less power (or as a safety measure in a series/parallel setup in case one sub goes caput, the impedance goes up instead of down and shorting the amp).

You can wire all four inputs using the two high lever speaker inputs that you have. That's not a problem. One time, the neighbor kid had 6 amplifier channels wired up to the same single channel input from his half broken head unit! Worked fine but couldn't fade speakers or adjust the sub. But you will want to make sure to use the input filters on the amp. Your plan to use two channels for the main speakers and the other two for a sub will work - no issues.

The car audio bug can be strong. I've got way too much audio gear sitting on the shelf either waiting to go in "just to see how it sounds", or having pulled it out just to "see how something else sounds..". Yeah, I have issues. Haha.

 

Cool.
I know the stuff I bought is cheap, lower quality. But I paid $41 for all of it. Anything would be better than the factory rear door speakers. I would've simply replaced the rear door speakers, but I don't think the HU is putting out the same wattage to rear as it is the fronts. So, a small amp it is. And since I'm installing a small amp, might as well do a small sub, since I can now.
It's a base model truck. Work truck and commuter. I listen to talk radio half the time and don't really blast the tunes while driving. So, I'm not really looking for a high end set up. This is just for that occasional AC/DC tune that comes on while driving home from work and I wanna crank it up a little.
Being cheap, the little Pyle sub didn't come with much for specs to determine enclosure size. Can't find anything online for this model either. I read .6 - .8 cu ft for an 8" sub.
That sound about right?
(Also, it's SVC, not dual).

 

I have a nice micro amp I no longer use. Let me know if you’re interested. It powered my mids and highs in my BMW.

Just remembered, it’s a Soundstream Picasso amp.

 

Not trying to knock your decision, so don't misunderstand. Like you said, you paid all of $41 for it so let it rip!

I'm not seeing any T/S specs for it, either. Too bad shipping would be a bear or I'd measure it for you and see what kind of box it needs. But, most likely you would be in the ballpark with .5-1 cu ft sealed. I probably wants a bigger impractical box to get a more optimal system Q, but shrinking the box will put a natural bass boost in the upper bass. Stuff some PolyFil in the box and see how it sounds.

 

No, I know. Just letting you know not to try talking me into getting better stuff. I have enough problems
Last thing I need is another hobby or pile of projects and parts laying around.
But I already know how this will play out.
"I'll just get this cheap shit, it'll be good enough for what I'm doing". Yeah, we all know what will happen a year from now.

 

I promise not to make you eat the chocolate cake. I can't promise that I won't show you the chocolate cake...