Help! No Midbase! C-400 + db6500s ??

ravaneli

Here is what I have in my Nissan Maxima

Head unit -- Kenwood 790 Excelon

4 x Polk Audio db6500 speakers on same locations as factory. Tweeters mounted high on the columns.

C-400 Polk Audio amp feeding the speakers only.

SPL5000 Pioneer mono amp . Tsunami 5 Fahrad capacitor feeding it.

SPL3000 Pioneer Sub

My Problem: I can't hear almost any mid frequencies through the speekers! All of my components are of high quality (and price) and I must have some settings wrong. Base is good and highs are loud and clean but no deam mids!

I have not used any filters on the head unit. The C-400 crossovers are set up to HP and 50hz. At 12 db. Gains are about 50%.

Any ideas for wrong settings appreciated. My old car had lower rated pioneer speakers and very cheap amp and no subs at all but the speakers were KICKING HARD. There is no reason this setup should do any worse.

Is there anyone from Chicagoland around? I would love to show my setup to someone and get advice. If really helpful I can pay too.

I put around $2K in audio and must have good sound. Help please.

[Deleted User]

Do you happen to have the EQ switch set to "on" on the amplifier? Check to see if the "dial" on the crossover of the amp is not spun around 180 degrees making it appear to be on 50Hz when it's more like 350 Hz. Re-check your HU, too. Make sure it's not highpassed.

ravaneli

All of you suggestions make sense. Thanks!
HU filters are off.
The amp filters are on 50 hz, i checked again. Just to make sure I turned crossovers off and it made no audible difference.

The pre EQ switch is ... well it says bypass. I don't know if it's bypassing the HU or the amp settings. But Pre-EQ is not on.

I am really desperate, t makes no sense. I plan on buying spectrum analyzer to better see what I am missing but when I put my hand on the mid drivers there is just no punch at all even on hip hop stuff. And you can hear there is no mids.

Now I am thinking that the "dude" who installed the speakers might have wired the crossovers wrong. May be he wired the tweeter output with the mid drivers and vice versa? Is that possible? Any trouble shooting advice?

PoweredByDodge

highs + lows, but no midbass.... sounds like you have the sub out of phase with the highs... flip the + and - leads on the subwoofer... see what happens.

ravaneli

I have reversed the phase of the sub from the head unit already. Isn't that the same? also how does the phase relate to the mids? May be I was unclear. It's the mid drivers (6.5" db6500s) that are NOT KICKING AT ALL even at max volume that will rip the trunk of my maxima apart..

PoweredByDodge

doesn't always work that way.

do this....

1- pull the remote line off your sub amp so it wont even turn on.
2- play a cd with just your highs on and see if the midbass is back.
--- if it is, then you have a phase issue.

3- if its not, go kill that "guy" guy.

Thom

Try pushing the button for the "Polk EQ" and see if that does it.

If that's "on" the fronts are high passed at tweeter frequencies, and the rears are low passed. It's meant for bi- amping older Momo components, but by labeling it "Polk EQ" some guys just push the button. Or sometimes it gets pushed by accident.

1996blackmax

ravaneli wrote: »

Now I am thinking that the "dude" who installed the speakers might have wired the crossovers wrong. May be he wired the tweeter output with the mid drivers and vice versa? Is that possible? Any trouble shooting advice?

Why don't you think before making ignorant comments like the one above....

PoweredByDodge

1996blackmax wrote: »

Why don't you think before making ignorant comments like the one above....

... *tilts head* why do you say that's an ignorant comment?

1996blackmax

Read it again....

PoweredByDodge

Good point... the >3 kHz tweeter output would likely be near inaudible on the midbass, and the mid out would thrash the tweeters in a day or two.

Thus, I conclude, that's an ignorant comment.

1996blackmax

yeah right ........

ravaneli

1996blackmax wrote: »

Why don't you think before making ignorant comments like the one above....

I have just recently started looking into audio set up and I am indeed ignorant on most of this. It would not have made a difference if I had thought about it because I just don't know if it's possible. Should you pay closer attention to the format I used you will notice that I am asking a question and not making a statement. I see nothing wrong with that. Why don't you think before you make arrogant comments like this?

1996blackmax

I was not referring to the audio question. I originally came into this thread to try to help.

I see Josh took care of what I was talking about.... "dude" is a much better term to use than what was originally in your statement... maybe you should have thought a little more before posting the original comment.

MacLeod

What did I miss? I dont see anything wrong with his statement.

The mids can play well over 3 KHz. My SR 6500's played well up to 8 KHz with authority! This could very well be a possibility. However, chances are the tweeter wouldve blown sky high trying to reproduce 80 Hz notes by now.

Vinny is right that an out of phase sub can cancel out midbass but if the midrange driver isnt moving at all (which I inferred from his NOT KICKING AT ALL statement), thats not a problem with phasing.

ravaneli

the mid drivers are not dead. They make sound but only high frequencies. And when you put your hand on the speaker there is no kick on the beats.

I switched the + / - cables in the sub. May be it's just me but I think I like the bass better now. However this had no effect on the mid drivers. And by the way as it is now the phase is reversed from the HU and then the wires are switched at the Sub box posts. Can I just make the phase normal from HU and switch the wires back? Is that the same thing?

Back to the amp. For third time I verified that the HP filter is @ 50hz for sure. And the Pre-EQ is off (says bypass)

I need help how to find out where the problem is. I have extra speakers and even 2 extra amps that I havent returned yet. How can I perform some tests to track down the problem?

I still fear poor wiring of the crossovers. The tweeters are wired correct though, because they play nicely and could not reproduce lower freq. Just to exclude this possibility I am thinking of disconnecting the rear speakers from the amp and connecting my old pioneers that have no crossovers to see if they will beat.

If that doesnt help I think I will plug the other amp (Boss) to see if it can make a difference. Alas I dont have extra HU but if nothing else helps I might go get one from walmart or bestbuy or whereever and make a test and then return it (please save me ur morals again).

This is the only think I can think of. I am open to any suggestions as I am as you can see quite desperate..

Jack from Indo

First of all I wouldn't try to get to the bottom of it with spectrum analyzer software as per your other post. That's for fine tuning. You already know you got a problem.

Or do you?

Are you mistaking the loud "thump" from your old pioneers for good quality sound? In any case, do you still have the old pioneers? I would put them in the back holes, and then use your fader to listen first to them, then to your polks, and go back and forth. Keep in mind that depending upon the speaker rating, one set may be more or less loud than that other as you switch back and forth - don't confuse that with quality.

Also keep in mind that most (all?) good speakers need a breaking in period, for the midbass to come out well - but the difference is not black and white, just noticeable. If this problem is severe, breaking in will not solve it.

Find another install shop, tell um your not happy with the other guys, and ask them to have a listen. That will very often get you a bit more free help than otherwise, as they are always pining to show up the competition. Nothing immoral about that. It's called capitalism. Make sure you find a place that pros use.

ravaneli

No, I dont want to disassemble the rear deck. I will just take the wires for the rear speakers out of the amp and plug other wires and connect them to my pioneers and hold them in my had (would that work).

I do have a problem. It's not about breaking nothing. There are no mids whatsoever. If I turn off the sub the sound is flatter than my headphones..

MacLeod

A better test would be to run speaker wire straight from the amp to the mid bypassing altogether the crossover. If it sounds right, then the problem is with the x-over and its likely wired backwards.

This should be the first test. If it still only plays highs then something along the lines of settings is wrong.

1996blackmax

MacLeod wrote: »

What did I miss? I dont see anything wrong with his statement.

Some post were edited by the power of Grayskull .

PoweredByDodge

MacLeod wrote: »

What did I miss? I dont see anything wrong with his statement.

The mids can play well over 3 KHz. ...

Vinny is right....

1- I intentionally 'played dumb' and 'thought' that the 'ignorant statement' was about a technical issue.

2- I know... but I was trying to find some B.S. to put in there and flesh out item #1

3- I usually am... unless you go back into the archives and read some of the stuff I was spouting off a few years ago... holy 'way off batman'. I tend to run my mouth more than my truck.

P.S. I suppose some might be upset if their sarcastic posts are edited... I, however, am honored to have been smote'th by He-Man. He's quite a strapping young lad. ((has anyone noticed that the voice of the 'new' Skeletor in the recent He-Man cartoon is very Frank Welker sounding? I thought the guy was dead, but I guess he's voicing Megatron in the Transformers live action movie. Peter Cullen for Prime to boot. Can't pass that up. If only Chris Latta hadn't O.D.'d on coke or whatever he was taking. That was one hell of a sad death... dude just got all messed up, passed out, and died. Guess Starscream really did lose in the end.))

PoweredByDodge

Thread carjack...

I see Mac's got like 10k posts. Holy schmoley... schmolini... schaling-a-ding. What's the maximum 'rating' you can have. Like I see 10k gets you 'Polk Guru'. What does say 1x10^(infinity) posts get you... Polkasaurus Rex? (I think Paul DiComo had that).

ravaneli

can an admin delete this and the previous 3 posts please? I still hope to find some help. I will be running new wires to my old pioneers today after work and will post results later.

[Deleted User]

Uh-uh. He-man says that's a no-go.

[Deleted User]

BTW, I think you have a x-over problem. Are they inside you doors? I'll bet they are all screwed up.

PoweredByDodge

Josh wrote: »

I'll bet they are all screwed up.

Is that your technical diagnosis. "Yess-a we be findin' that yo' cross-a-ma-ova's be all screwed up!"

Back to being serious though, and to the original poster, we are trying to help you out -- we (well, me) just get sidetracked now and then.

Ok -- you tried the switching of the sub + / - leads, and it didn't help you out. But you said the bass was better... so -- put the + / - leads back to normal and then set your head unit sub-out to "in phase" or "normal" or whatever is "regular" (not out of phase like you have it set now).

Here are some more ideas:

1- Do you have an crossover built into your head unit. If so, you may have it set at something higher than the crossover on the amp. If the amp is set at 50 Hz, but the head unit is set at say 200 Hz, then you're only going to hear 200 and up out of the mids.

2- If you have a crossover built into the head, and you have it set low (like, any setting other than completely 'off'), you may be experiencing a mix of a steeper slope and phase issues. Everytime something is crossed over, you have a phase delay proportionate to the steepness of the slope. So when you run two crossovers back to back (one on the head, one on the amp -- and hell, even one in your door or whatever makes 3) then you end up with a slope that is the sum of all of them put together.... and a phase lag that is the sum of all 3 as well. What I'm saying is that you're mids might be outa phase with everything (not necessarily 180 degrees out --- but anywhere from 90 to 270 or in between) because of this.

3- Physically damaged passive crossover (the one that came with the speakers). But that would be more likely if only one speaker were acting funny -- both speakers acting odd usually means its not such a simple problem.

4- Loudness control... BBE... or anything like that... these controls boost bass and trebble intentionally... dropping the mid down or leaving it flat. If you have a peaky system to begin with, and then you use a loudness button or bbe or whatever, you may find that you have 'no' midbass. I realize this suggestion is much like the "do you have an eq" suggestion, but maybe you overlooked the loudness/bbe deal as you may not have considered it a type of equalizer.

5- *bashes head off wall* -- i dunno, pinched wire somewhere?

ravaneli

Haven't gottnet off of work yet.

About HU settings:
The Kenwood 790 Exelon has 3 pairs of RCA outs if that matters, so I have separate pairs going to the amps.

The HU has x-overs for F/R/ Sub. F & R are off. Sub is set to LP 120hz. The Sub amp is set to LP 120 too, I think I need to turn one off, but which one?

I do habe a loudness control and it is ON. I don't even know what it's doing. How is it supposed to be?

The speaker X-overs are in the front doors and the trunk respectively. THey are not broken because the highs are good.

My sound is clean and noise free, bass it tight and sharp and non clipped. But something somewhere is filtering the darn MIDs completely, while passing the lows and the highs. But yeah, there are way too many crossover in my systems and just way too many settings and i dont understand half of them. Again, anyone from chicago here??

[Deleted User]

It can be possible for the crossovers to be broken and still have limited function. Also turn OFF the loudness setting. All that does is boost your highs and lows. That may be your problem but I still think it's something else.

MacLeod

Or they could be wired backwards.

Do like I said - run a set of speaker wire straight from the battery to one of the offending mids and bypassing the crossover. If it plays right then you know the problem is in the crossover. If it still plays only highs then its elsewhere. Doubt very seriously if its defective speakers or crossovers cause the odds of both sets being bad are pretty slim.

PoweredByDodge

As Josh said... turn loudness off...

Also - turn off the subwoofer crossover on the head unit -- leave the one on the amp on.

ravaneli

FOUND IT !

Well almost.

First I took my old pioneer speekers and hooked them up to the amp instead of the rear speakers. I was just holding them in my hands to see if they kick but no difference.

Frustrated and angry I took my top off and started unhooking the amp. Then I hooked my old cheap Boss 4 channel amp and OH MY OH MY!! The speakers almost jumped out of their slots as the radio was turned up very high! Nice and Solid Mids and the membranes were just jumping back and forth like crazy. Balsam to my eyes and ears. I tuned up the gains and the x-overs and made the wiring a little less ugly ( I was just trying) and left it like that.

Now... what am I Supposed to do with the Polk C-400? I tried every setting possible, just to find a difference but to no avail. Can the X-overs of the amp be bad? Or is there a switch that I don't know of? Do I ship it to manifacturer (its in waranty) or do I need to check it somewhere first? Please advise.