Swapped speaker and amp, door speakers full range

[Chimera]

Originally Posted by LimitedSlip

First, here is a link to download the manual for the Alpine amp:

http://support.alpine-usa.com/produc...45U.pdfhttp://

I think there may be a misunderstanding about how the filters work on this unit.

A "High Pass Filter" (HPF) is designed to allow all frequencies ABOVE a certain cutoff (or crossover) point to PASS THROUGH the filter.
Conversely, all frequencies BELOW the cutoff point are BLOCKED from passing through.

This amp appears to have two modes of operation:

1. Full range - The HPF is disabled and ALL frequencies (bass and treble) are amplified and passed through.

2. High Pass - Only the frequencies above the cutoff point (treble) are amplified and passed through. The frequencies below the cutoff point (bass) are BLOCKED.

If the goal is to send only the bass frequencies to the door speakers then the Alpine amplifier must have the HPF DISABLED. But, this doesn't achieve the entire goal because while the bass frequencies are now being sent to the speakers, so are the high frequencies.

If this amp is to be used for bass only, there needs to be some kind of crossover or "Low Pass Filter" ahead of it to block the high frequencies. Or, maybe this amp isn't the best choice for this application. An amp with a built in LPF or complete crossover might be a better choice.

As for disabling the tweeter, this is kind of a bad band-aid on the problem and not an actual solution. Even with the tweeter disabled, the bass speaker is still trying to produce all the frequencies being sent to it even though it's not very good at producing them. Best to only send the bass frequencies to a bass speaker if you want the cleanest reproduction.

Agreed, however he already owns this amp, also amps that are 15A that work in this application are somewhat limited. If I was looking to LPF the speaker, I would use 2 coils inline with the output side, or replace the speaker with something that has a desirable natural rolloff. or both.

@LimitedSlip s point is valid though, using a real crossover would accomplish the goal better than cutting out the tweeter. a .398mH inductor on each output would give you a 800hz 1st order lpf on each of the doors. you can get things like this from digikey. be sure to select parts that can be ordered individually, there are things on there with min order sizes of 1000 for example.


link to a first order crossover calculator
http://www.erseaudio.com/CrossoverCa...st-Order-2-Way

[B-R-Z]

Yeah I have those. I used the white PVC adapters that someone makes, I forget their name. I think you need spacers regardless of speaker selection pretty much, right? They are cheap.

[Chimera]

Originally Posted by B-R-Z

Yeah I have those. I used the white PVC adapters that someone makes, I forget their name. I think you need spacers regardless of speaker selection pretty much, right? They are cheap.

Bc I'm curious, are you running it on any crossover, or are you feeding it full range and letting it roll off naturally?

[B-R-Z]

Originally Posted by Chimera

Bc I'm curious, are you running it on any crossover, or are you feeding it full range and letting it roll off naturally?

The amp has a high pass filter built into it for mids/highs. For the mid-range (RS180), I am using a coil enclosed in a radio shack project box which acts as a low pass filter, creating a bandpass filter.

[soundman98]

i've got a better question. why the hodge-podge of equipment? infinity, alpine, and jl all have drastically different sonic signatures, and i suspect part of the issue is the intermixing of those signatures. there is absolutely nothing wrong with mixing speaker brands, but doing so requires forethought and planning with each brands characteristics in mind.

Originally Posted by daskaman

Hi guys,

I ended up swapping all speakers, hu and did a mini Alpine amp (alpine ktp-445u). Door speakers are Infinity 6032CF (component)

so you're using the oem deck with the infinity speakers wired to the alpine amp?

Originally Posted by daskaman

The doors currently sound way to bright. There is a 0db and +2db switch and both ways including directing the tweeter or even blocking it, sounds way too bright and cant keep up with the rest of dash speakers

so you have a full component set installed in the doors? definitely not needed with speakers installed in the dash. only the midbass is needed in the door. the tweeter and crossover installed here is only complicating things.

Originally Posted by daskaman

(Alpine SPR-10TW tweeters and JL CZ-350x 4'')

later you mention that the oem tweeters are still installed with the implication that they're still powered?
what crossovers are being run on the alpine tweeters, and how are the jl mids wired and crossed over?

Originally Posted by daskaman

These might be some basic questions because i'm new to this. The amp I have doesn't have a crossover for high frequencies, only low. I feel like the doors had way better punch with the original speakers in place. Is this a combination of doing preamp low on amp and adjusting base from hu?

My question is how to make this speaker only do bass as a factory set up?
Is it beneficial? Can I just cut the tweeter out to kill its high frequency?

Any ideas?

the first idea i have is to get a proper amp with adjustable highpass/lowpass capabilities. or if you're married to that specific alpine amp, and what i assume to be the oem deck, you will need to get an external crossover to properly route all the audio signals.

[daskaman]

Originally Posted by soundman98

i've got a better question. why the hodge-podge of equipment? infinity, alpine, and jl all have drastically different sonic signatures, and i suspect part of the issue is the intermixing of those signatures. there is absolutely nothing wrong with mixing speaker brands, but doing so requires forethought and planning with each brands characteristics in mind.



so you're using the oem deck with the infinity speakers wired to the alpine amp?


so you have a full component set installed in the doors? definitely not needed with speakers installed in the dash. only the midbass is needed in the door. the tweeter and crossover installed here is only complicating things.


later you mention that the oem tweeters are still installed with the implication that they're still powered?
what crossovers are being run on the alpine tweeters, and how are the jl mids wired and crossed over?



the first idea i have is to get a proper amp with adjustable highpass/lowpass capabilities. or if you're married to that specific alpine amp, and what i assume to be the oem deck, you will need to get an external crossover to properly route all the audio signals.

Ya the speakers mix match I know is not the best. I was shopping mostly by best deals i can find. All speakers have been swapped. To add to the mix n match the HU is a Pioneer DEH-X8800BHS.

All speakers are using the oem wiring, with the exemption of the re-pin to use the Alpine amp. Never once did I think about low pass filters through the whole process, just high pass filters. Honestly never even knew they were a thing.

The other learning curve was that some low pass filter is used with the original amp, which is why I thought "no worries, swap speakers, install amp and send more juice to the speakers". That combined with component door speakers really fudges up all the positives I have done and what it can be.

Always learning

[soundman98]

if you're using the factory wiring, how did the alpine get wired in?

[daskaman]

Originally Posted by soundman98

if you're using the factory wiring, how did the alpine get wired in?

I simply repinned a few wires. Somebody did an in-depth post titled "reusing oem amp wiring" to that exact model of amp.

[Chimera]

It's a fairly common mod, a few people on this forum have done it.
Running along a similar path to @daskaman I was running The 445u bridged running into a pair of cdt ex-30 with the woofers and tweeters from alpines spr-60c along with dayton audio 4 in in the front of the car as well as infinity 3.5 coax speaker's in the rear of the car. I ran that set up nearly 2 years before replacing it recently

[soundman98]

so my recommendation would be re-wire the amp.

change the amp so the rear channel is going to the door drivers, using the subwoofer output of the radio to enable the in-deck low-pass x-over. ditch the door tweeters and crossovers. shoot for 200hz crossover.

then alter the amps front output to go to the dash speakers, connected to the 'front' output. this would allow you to tweak the levels between the door and dash better, as well as enable the high-pass for the dash. so the doors become more of a sub. the dash should be high-passed around 150-200hz. it can go lower, but free air dash speakers don't really reach that low, especially automotive-grade drivers.

the rear output of the deck can still go to the rear speakers, if you feel you need them. i haven't ran rear speakers in over 15 years, so i don't.

[soundman98]

Originally Posted by Chimera

It's a fairly common mod, a few people on this forum have done it.

that might be. i'm not very up to date on the platform at all. i only recently stepped back into here because other forums i frequented are getting quieter, and it's cheaper to sit around and talk on forums than mod the car.

though it does nothing for the ideas i constantly have.