New crossover. Got engine noise

[ppia600]

Originally Posted by Simbalage21

Cool thanx a million... Yea if now I knew what to set it and the amps crossover at. Currently I got my amp at 200hz and not using the radio crossover... 200 is just to get me by till i order some components... Then I will be posting to ask.. .HEcK I'll ask ahead.. With good components.. what would be best setup amp to full and use sony crossover in radio.. or radio set to full and use the amp variable crossover. And to what point for good set of components if I use the amps Xover. Radio only has the 2 listed above post

Use the one in the deck, set to 125hz and the amp crossover to full range. If that doesn't give enough mid bass drop it to 78. Be sure so seal your doors well. You can always run the deck full range and try with the amp if it has a variable frequency control, might be easier to match the speakers. Try setting them up without the subs at first to listen for distortion.

[Simbalage21]

Originally Posted by ppia600

Use the one in the deck, set to 125hz and the amp crossover to full range. If that doesn't give enough mid bass drop it to 78. Be sure so seal your doors well. You can always run the deck full range and try with the amp if it has a variable frequency control, might be easier to match the speakers. Try setting them up without the subs at first to listen for distortion.

Quick responses your awsome. another question, and I promise to give ya a rest.. before i go try that.. there is also a lowpass. my monoblk has built in xover which is set to 60hz.. you cant turn it off..am I good there with the LP on deck at off?also if I wanted to add some "Woofers" to get more midbass would this be good.. or will them components solve the problem? also if they use passive wont the 2 crosovers conflict? or will it just drop low low bass.. and the passive sort out the frequencies from whats set on the deck to mid-tweeter? Also the kac has upto 200hz variable.

[ppia600]

You can try tuning the mids with the amp's crossover first and see where it sounds best. Depending on how close it is to the deck's internal crossovers if you end up being really close to 125hz you can just use the amp's crossover or the deck. It may sound better being able to use the variable crossover.


For the subs, I'd use the lowpass in the deck at 78 if possible, 60 is kind of low unless you have components in tuned enclosures allowing lower response to get better midbass. Sounds odd the amp's crossover won't go higher than that, they usually go up to 150-200hz even on class 'd' amps. If you HAVE to use 60hz, run the sub output on the deck on 'full' or 'off', you don't want to lose too much low level audio, the mids might not be able to make up for the difference.

Originally Posted by Simbalage21

Quick responses your awsome. another question, and I promise to give ya a rest.. before i go try that.. there is also a lowpass. my monoblk has built in xover which is set to 60hz.. you cant turn it off..am I good there with the LP on deck at off?also if I wanted to add some "Woofers" to get more midbass would this be good.. or will them components solve the problem? also if they use passive wont the 2 crosovers conflict? or will it just drop low low bass.. and the passive sort out the frequencies from whats set on the deck to mid-tweeter? Also the kac has upto 200hz variable.

[Simbalage21]

Originally Posted by ppia600

You can try tuning the mids with the amp's crossover first and see where it sounds best. Depending on how close it is to the deck's internal crossovers if you end up being really close to 125hz you can just use the amp's crossover or the deck. It may sound better being able to use the variable crossover.


For the subs, I'd use the lowpass in the deck at 78 if possible, 60 is kind of low unless you have components in tuned enclosures allowing lower response to get better midbass. Sounds odd the amp's crossover won't go higher than that, they usually go up to 150-200hz even on class 'd' amps. If you HAVE to use 60hz, run the sub output on the deck on 'full' or 'off', you don't want to lose too much low level audio, the mids might not be able to make up for the difference.

ahh so you try and match the high and lowpass? I mistaken. Its set at 60hz and is also variable, to I believe 150..but u cant turn it off.

So if I am following you.. 78hz on the lp 125 on the hp via deck.. then what does the monoblock xover goto if the deck is supplying the xover frequency? Man I feel special now.. As I try to move into higher and correctness, your helping with what I got, and what to buy as I go... Mad props for your help

[ppia600]

Cool, just simplify it and use the crossovers in the amp. You want to tune the mids first to get them to play as low as possible without distortion. If they can play with the amp's high pass set to ~100-120hz for example, let them do it. Then you just tune the bass amp starting from a low number and turn the knob up towards 100-120 until it sounds just right to you. You don't want it to be a higher low pass frequency than your high pass is set to ideally or there will be a frequency range that is pretty muddy and exaggerated. Ideally you want the amp's low pass for the subs set as low as possible (as long as the mids can fill in) so it sounds like the music is coming from the mids, you don't want to hear voice coming from the trunk for example.

Originally Posted by Simbalage21

ahh so you try and match the high and lowpass? I mistaken. Its set at 60hz and is also variable, to I believe 150..but u cant turn it off.

So if I am following you.. 78hz on the lp 125 on the hp via deck.. then what does the monoblock xover goto if the deck is supplying the xover frequency? Man I feel special now.. As I try to move into higher and correctness, your helping with what I got, and what to buy as I go... Mad props for your help

[Simbalage21]

Originally Posted by ppia600

Cool, just simplify it and use the crossovers in the amp. You want to tune the mids first to get them to play as low as possible without distortion. If they can play with the amp's high pass set to ~100-120hz for example, let them do it. Then you just tune the bass amp starting from a low number and turn the knob up towards 100-120 until it sounds just right to you. You don't want it to be a higher low pass frequency than your high pass is set to ideally or there will be a frequency range that is pretty muddy and exaggerated. Ideally you want the amp's low pass for the subs set as low as possible (as long as the mids can fill in) so it sounds like the music is coming from the mids, you don't want to hear voice coming from the trunk for example.

ok cool, I have learned a lifetime of knowlege in 5 minutes. When you say go as low as possible on the mids, how will you know your too low? Getting into quality seems the higher the frequency the less distortion, lower more distortion.. So Would I have to lower the gain to achieve lower frequency? and is there where I would 100% notice better results using the expensive components? aka better speakers taking more power & A Lower Frequency? I am sorry if I bugged you.. You dont know how much a difference you taking the time to explain this to me really means to a newbie comming into quality. I hear everyone in my neighborhood with bass and distorted vocals and I want to overcome this by all means.. doing so means learning 2 buy the right stuff this time around

PS: Do you use a test tone to achive this or regular music you listen to?

[Simbalage21]

Originally Posted by ppia600

500 is too high if the high pass slope is about 12db like most outboard crossovers because if the speaker has low sensitivity in the frequencies below that (500 down to 65/70hz) you won't hear anything below 500hz and it will sound like the midbass is coming entirely from the rear i.e. you'll have a portion of the sound missing. You want the mids to play as low as they can efficiently do so the image comes from in front, not the trunk. A lot of people run a really high high pass for the mids and highs to prevent distortion but the distortion is usually caused by something else like bass boost on the deck that makes it through the crossover or lack of power for example.

When I put a system together I prefer:

Deck with good crossover, hp in front and rear about 70/80hz and low pass for the subs about 70/80hz
Amps with no crossovers or crossovers set to off/full range

or

Deck with crossovers set to off/full range and amplifiers with good crossovers set to the frequencies same as above

In both situations its good to use passive crossovers for the mids (if you're running components) to help keep some of the highs from the mids and make them more efficient at producing their intended range. Nowadays subs can run with no passive crossovers because at those power levels they are very inefficient and sap tons of power. A decent crossover in the deck or amp is sufficient for subs most of the time. I don't like using outboard crossovers as internal deck crossovers and internal amp crossovers have improved over the years and prevent noise issues (like yours) and also added distortion which no one likes.

The new amp Got is a Coustic Power Logic Amp Model - Amp 360
I have this running to my rears, KAC-927 to the fronts (by Itself now not with rears) as well as the monoblock. I swapped out the Kenwood for the sony.. I know its cheaper but it has built in crossovers. My question being for that Coustic being 65W RMS it reallly put alot. I have the gain all the way down otherwise my rears pop with the bass. As you may know its an old school without crossover. If I set the crossover on the deck at 125 or 75 (i belive) then both front/rear rca output are effected.. but sub output is not. Would the stock preset xover frequency sound better at the deck for both amps, or should I leave it off and keep the rears at full and the fronts set with the amps built in variable xover? The crossover I bought I sold it thank god.. so that solved my engine noise.. but what would be the best way to set this up to the correct frequencys? Also I am thinking about putting the diamond xovers I got that go on the speaker side. Can you use a passive crossover with active crossover set? (VIA Deck or amp) or will they conflict? I only ask because I have a 11Uf (a cap off a 6x9 tweeter) for my tweeters, and mids directly to the amp and many say this is not sufficiant.. How would I get active and passive work together.. as I am still confused about using 2 crossovers..

[Simbalage21]

Ok recap

Sony Headunit (3 Rca outputs) [sub/rear/front]
Kac927 2channel amp (on Fronts)
Old School Custic (On Rears)
Monoblock (On Sub)

I set all crossovers to full EXCEPT on monobock.
Set headunits HP to 78 (which appears to crossover front/rear)
Set headunit LP to off (Because on the monoblock you cant turn it off)

Installed a set of diamond crossovers to replace the caps I was using for the tweets (From blown 6x9) on the front speakers...

Rears are coaxial and I've set the gain on this amp a lil lower...


Is this optimal setup with what i've got now? also should I cross the monoblock to 78 to match the HP of 78?

Thanks in advanced. Here is some pics of the speakers in front and crossovers I installed...