1999 Honda Prelude 2 amp sound system, sub amp causing speaker interference?

[ErosTheLude]

So a couple months ago I completely rewired and replaced all of my stereo system. Before then I just had aftermarket speakers, and a subwoofer. That wasn't good enough so here is my build.

Stock Honda AFS Headunit (either I hated the look of the aftermarket head unit or the sound quality was inferior to the stock head unit)

Honda Aux input add on (made by Honda, great audio quality so I don't need an aftermarket one yet)

Fierce Audio Line level converter to get around having an amp with Line level input,

Clarion 9 Channel Equalizer, 4 speaker output, subwoofer output, and an additional aux in that I don't use.

Set in a bell curve. Used to be an av tech so I am on the hunt for an oldschool single din Graphic EQ. They no longer make them so its proving difficult.

Alpine MRP F-300 four channel amplifier Set at 12 oclock for power. Didn't mess with anything else

16 gauge copper braided speaker wire expertly run. I tore my entire interior out to run it. It was a pain in the ***.

Doors

Infinity Reference 6032cf 6.5" custom mounted (stock speakers are 5.5") 60 watt rms

I am getting a little door rattle at the range that causes my ears to bleed but I know what I need to fix.

Rear Deck

Alpine Type R 6x9's 60 watt rms. They are older cone style speakers however they make better sound than the infinitys but that might just be the door rattle

Subwoofer *in progress*

Infinity 12" sub, building custom fiberglass box next week cant wait

Current sub

Old 10" Pioneer in sealed box

Sub amp (I know its crap but I haven't replaced it yet)

Pyle 2 channel bridgeable 1000 watt amp. Its set to 75%. I know its not pushing that much but I haven't had any issues till now.

In line with the amplifier trigger wire I have a switch for each amp to turn it off.

My problem is that when the subwoofer is on I get a syne wave over the speakers. I turn off the radio and leave the amps on and its there. I turn on just the speaker amp and leave the sub amp and the radio off and get nothing. The way I wired in the sub trigger I can't have the sub amp on without the speaker amp on, but I can turn off the sub amp with the speaker amp still on.

I think the distortion is mainly from the rear speakers, I have heard it oscillate when flooring it so it may be caused by power however when the sub amp is off I get no interference.

my rear deck and sub woofer wires are run in a group and pass by the sub woofer amp. Is this the cause of the sound? I think it is. It only happens when the amp is on so it isn't the power wire. It must be the amp. Could the amp send interference back through the channels when it hits hard?

When I listen to a particularly bass heavy song it sounds like **** through the speakers when the sub goes off and only when the sub goes off.

Please help me. I put way to much time into my car to loose to a **** amp.

I did up a diagram that would relocate my amp to the trunk and the power down the passenger side and the speakers down the drivers side. Do you guys think this will solve the noise issue?

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[Jepalan]

How is the HU connected to the RCA inputs on the amps? Have you powered up both amps but removed the RCA inputs from the sub amp to see if the noise stops? I am just wondering if the sub amp is effecting the other amp via the inputs.

 

[keep_hope_alive Premium Member]

welcome. sweet car! H22A???

so first is to ditch the Pyle amp. they do not have adequate filtering and will add noise in the system. For now, just run the 4 channel amp, run the fronts and rears in parallel (2 ohm load) and bridge the rear channels to the sub (assuming 4 ohm SVC). that will immediately solve your noise problem and give you almost the same sound you have now.

i've owned and used the Clarion EQS746 before. it's ok. the older Alpine ERA-G180 is what you describe you want. I've also used an Audio Control EQL to act as an EQ and LOC with a Honda stock head unit with good results. with a stock deck, an external EQ should have high-level inputs to eliminate a cheap LOC.

the LOC you have is mediocre. the F300 accepts speaker level inputs directly and the less things in the signal path, the better. wire front and rear to the F300 and you can use Fader as a quasi-sub level control.

note that the output from most headunits is balanced (but without a drain). so a LOC just reduces voltage and converts from balanced to unbalanced via resistor networks (passive). the amp will accept these balanced inputs directly through the high level inputs - minimizing gain at the amp and lowering noise.

note you will want to limit HU volume to 50% or so due to THD inherent in the head unit amp (granted the impedance load is much higher)..

a good head unit can solve most of your issues overall. It can provide a good parametric EQ, crossovers, time alignment, and will simply the entire setup. I run the Alpine CDE-HD149BT and am impressed with it overall for features and cosmetics. In general, I have good luck with Alpine.

 

[Babykinns 10+ year member]

welcome. sweet car! H22A???
so first is to ditch the Pyle amp. they do not have adequate filtering and will add noise in the system. For now, just run the 4 channel amp, run the fronts and rears in parallel (2 ohm load) and bridge the rear channels to the sub (assuming 4 ohm SVC). that will immediately solve your noise problem and give you almost the same sound you have now.

i've owned and used the Clarion EQS746 before. it's ok. the older Alpine ERA-G180 is what you describe you want. I've also used an Audio Control EQL to act as an EQ and LOC with a Honda stock head unit with good results. with a stock deck, an external EQ should have high-level inputs to eliminate a cheap LOC.

the LOC you have is mediocre. the F300 accepts speaker level inputs directly and the less things in the signal path, the better. wire front and rear to the F300 and you can use Fader as a quasi-sub level control.

note that the output from most headunits is balanced (but without a drain). so a LOC just reduces voltage and converts from balanced to unbalanced via resistor networks (passive). the amp will accept these balanced inputs directly through the high level inputs - minimizing gain at the amp and lowering noise.

note you will want to limit HU volume to 50% or so due to THD inherent in the head unit amp (granted the impedance load is much higher)..

a good head unit can solve most of your issues overall. It can provide a good parametric EQ, crossovers, time alignment, and will simply the entire setup. I run the Alpine CDE-HD149BT and am impressed with it overall for features and cosmetics. In general, I have good luck with Alpine.

Alpine FTW. Alpine head units have outstanding sound quality I run an older Alpine head unit the CDA-9807 but it has GREAT sound quality I love it lol.

 

[Babykinns 10+ year member]

So a couple months ago I completely rewired and replaced all of my stereo system. Before then I just had aftermarket speakers, and a subwoofer. That wasn't good enough so here is my build.
Stock Honda AFS Headunit (either I hated the look of the aftermarket head unit or the sound quality was inferior to the stock head unit)

Honda Aux input add on (made by Honda, great audio quality so I don't need an aftermarket one yet)

Fierce Audio Line level converter to get around having an amp with Line level input,

Clarion 9 Channel Equalizer, 4 speaker output, subwoofer output, and an additional aux in that I don't use.

Set in a bell curve. Used to be an av tech so I am on the hunt for an oldschool single din Graphic EQ. They no longer make them so its proving difficult.

Alpine MRP F-300 four channel amplifier Set at 12 oclock for power. Didn't mess with anything else

16 gauge copper braided speaker wire expertly run. I tore my entire interior out to run it. It was a pain in the ***.

Doors

Infinity Reference 6032cf 6.5" custom mounted (stock speakers are 5.5") 60 watt rms

I am getting a little door rattle at the range that causes my ears to bleed but I know what I need to fix.

Rear Deck

Alpine Type R 6x9's 60 watt rms. They are older cone style speakers however they make better sound than the infinitys but that might just be the door rattle

Subwoofer *in progress*

Infinity 12" sub, building custom fiberglass box next week cant wait

Current sub

Old 10" Pioneer in sealed box

Sub amp (I know its crap but I haven't replaced it yet)

Pyle 2 channel bridgeable 1000 watt amp. Its set to 75%. I know its not pushing that much but I haven't had any issues till now.

In line with the amplifier trigger wire I have a switch for each amp to turn it off.

My problem is that when the subwoofer is on I get a syne wave over the speakers. I turn off the radio and leave the amps on and its there. I turn on just the speaker amp and leave the sub amp and the radio off and get nothing. The way I wired in the sub trigger I can't have the sub amp on without the speaker amp on, but I can turn off the sub amp with the speaker amp still on.

I think the distortion is mainly from the rear speakers, I have heard it oscillate when flooring it so it may be caused by power however when the sub amp is off I get no interference.

my rear deck and sub woofer wires are run in a group and pass by the sub woofer amp. Is this the cause of the sound? I think it is. It only happens when the amp is on so it isn't the power wire. It must be the amp. Could the amp send interference back through the channels when it hits hard?

When I listen to a particularly bass heavy song it sounds like **** through the speakers when the sub goes off and only when the sub goes off.

Please help me. I put way to much time into my car to loose to a **** amp.

I did up a diagram that would relocate my amp to the trunk and the power down the passenger side and the speakers down the drivers side. Do you guys think this will solve the noise issue?

How much of your wiring is run together?

 

[bbeljefe]

I agree with kha. It's likely the amp but it could also be the LOC. A good processor with high level inputs will solve your EQ problems and send a healthy line level signal to your amps.

Also, "gain set to 75%" means nothing. It should probably only be set to 40% (or

 

[ErosTheLude]

The headunit has a fierce audio line level converter sending rca to the equalizer which has 6 rca outputs. 2 to the sub amp and 4 to the Alpine amp.

I powered up both amps and removed the RCA from the sub amp not the Alpine amp and the noise stopped. If I remember right that means that the amp has ****** filters. I was going to get a better one anyway. I have had it for 3 years and bought it for a car I didn't care about.

Yeah I love my H22A4. Having a 5 speed is awesome. Just replaced the exhaust headers back and it is perfect. Only makes noise on the acceleration. When I set the cruise control on its as quiet as stock.

I plan on ditching the amp and relocating the new amp to the trunk and reorganizing the amp location under my seat and getting a new head unit. I just need to pick one with a great equalizer that looks stock in my dash. Hopefully with 5 or 6 rca outputs, aux input. I don't need bluetooth compatibility, sound quality is what matters. Looking into Alpine for that matter.

When you say run the front and rears in parralell do you mean, Front left paired with front right on one channel and rear left and right on the other, or Front and rear left together and front and rear right together? When I throw the sub into the mix I don't think I would get good sound out of it because the amp wouldn't be removing the highs and mids from the mix. Unless I used the rear channels with the sub channel for the eq and the front channels with left and right rear from the stereo. Does that make sense?

The current setup turned into this frankenstein project that I plan to strip out when I get a head unit. In the 90's rockford fosgate made an amazing graphic equalizer, however they are now super rare and cost over $400 if they are for sale on ebay.

In defense of the cheap equalizer, I bought it 5 years ago with my first car because you couldn't replace the stock head unit and I wanted subs. So it has done the job well so far.

Since the F300 has speaker in are you saying when I do get that new head unit I should run Speaker wire to the amp for the doors and rear deck instead of RCA for better quality?

And Yes you have been a great help.

Any suggestions on an Alpine Head unit? I'm leaning towards double din as long as fitment looks stock, and it dims when I'm driving at night. I tried a ****** one a year ago and it didn't dim at night. I couldn't drive with that piece of ****. Got my money back for free though.

I am a AV Tech part time so I like being able to tweak the equalizer. If the headunit has a multichannel eq, and a graphic eq setting I would be sold if it sounds as awesome as it looks.

 

[ErosTheLude]

The rear deck and sub wires are run parallel, the front doors are together for 3 feet then separate.

I'm almost 100% sure it is the amp. Replacing the HU and amp just to simplify things though.

 

[ErosTheLude]

Thoughts on the CDE-W235BT or similar head unit? I don't want anything but sound, clarity, aux in, cd, and radio. Having the usb is more than I want. I don't like USB plug ins for the most part.

 

[ErosTheLude]

On a side note one the Prelude Online Forum a guy took a new Honda In dash nav system, with aux in, and radio ect, and wired it into a Honda Prelude dash. It looked like it was meant to be there and worked perfectly fine. What would you guys think of doing that instead of going with an aftermarket? I could get another line level input amplifier for the sub woofer and use the line level input for the alpine that I already have.

 

[keep_hope_alive Premium Member]

get a newer Alpine with the 9-band parametric EQ built-in (1/3 octave steps, Q adjustment, level adjustment). That is what an EQ-tweaker wants. And time alignment will help give you a soundstage and the crossover will also let you adjust points and slopes from the driver's seat. you will not regret this decision (illumination can be adjusted both intensity and color)

by "parallel" i mean left front and left rear together, right front and right rear together. ALWAYS maintain balance adjustment (left-right). you can sacrifice fader sometimes if need be (thought I prefer fader control also).

the single head unit will greatly simplify the system and give you the best sound quality with the fewest issues. Alpine has a nice selection of double-din head units if you feel the need for a touch screen. Just be sure to look for the EQ feature and you will also have 6-channel outputs.

sounds to me like an aftermarket Alpine head unit and new sub amp are all you really need (besides some speaker install treatments - see my build logs for what I do for speakers).

new Honda head units are problematic and annoying. I mod a Honda Accord forum and field daily complaints with stock head units. the adapters are expensive and when all is said and done the investment will be higher (stock deck + interface + eq/loc) than one new aftermarket that outperforms in every way possible. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[ErosTheLude]

Yeah I'm looking at Alpine now for one like that.

I'm going to remove the sub amp. but I won't rewire everything until I get the head unit and new amp. Honestly, mounting them beneath the seats is great until you try to tweak the settings or rewire stuff.

Here is that OEM navi build this guy is doing on prelude online. My OEM Honda Navi for the Lude - Honda Prelude Forum - Prelude Online.com

 

[ErosTheLude]

Can you tweak the EQ with your CDE-HD149BT like you can with the CDE-147BT? Do you know of a double din version like that? I don't want a full touch screen, just to get rid of the box beneath the radio.

The Tune It app has horrible reviews, what are your thoughts on it and Android?

 

[ErosTheLude]

Thoughts on this amp and head unit?

Alpine MRP-M500 Mono subwoofer amplifier — 500 watts RMS x 1 at 2 ohms at Crutchfield.com

Pioneer DEH-80PRS CD receiver at Crutchfield.com

EDIT:

Just checked my current amp. Its actually the MRV-F300. Even though I bought the MRP model they must have shipped me the new one by mistake. Mine doesn't have the grooves on the top like the MRP, its flat with two grooves on the top and bottom edge like the MRV. I also changed my mind to the MRV-M500. For some reason its the exact same amp, newer model, cheaper price. No idea why Crutchfield would recommend that instead of the new one.

So $120 for the MRV-M500, and either the Pioneer Deh-80PRS $250, or Alpine CDE-HD149BT for $250.

I am still not sold on either head unit. Honestly I am still on the hunt for a standalone Graphic Equalizer and find an Audiophile sound quality head unit. I like having the EQ control at my fingertips instead of going through menus which bug the hell out of me.

 

[keep_hope_alive Premium Member]

you couldn't pay me to run a Pioneer head unit, especially the 80PRS.

the 147 and 149 have the same features, the 149 just has the BioLite display which is totally worth the extra cost if you care about aesthetics.

the problem with a octave band graphic eq is the filters are too wide and you don't always want to adjust an entire octave band centered around 500Hz, what about a 1/5th band centered at 400Hz?

the iTuneIt is ok, fine for people that want to use their phone to tune the deck - it takes 10x longer than just using the controls on the faceplate so i don't really see the purpose except for people that understand a phone more than a head unit (it does make things more graphically friendly).

Alpine has logical menus, Pioneer tried to make it as difficult and cumbersome as they could.

pics of the 149:

Pandora control through Android via BT

i am filling the extra space with meters in my car, then making a custom mount for it all that will have a stock appearance.