So I figured I'd take today to try a new set of RCA's for my fronts that have that weird clicking/hissing until the volume gets above 4-5....yeah...didn't work. I guess it's gotta be the amp...(PDX 4.100). I was getting close to the same weird sounds with the PPI Art but when I used the ground loop it went away. That amp doesn't have a x-over so I'd need an external or processor AND I'd still have to use the ground loop. WTF! is going on here!!!




ALSO...

My subs were wired into Yellow w/ Black (+) and Light Green w/ Red (-) which are post-amp. So I figured while I'm at it I might as well wire the sub into the pre-amp (should have done it when I removed the LOC but whatever). I wired the subs into Red w/ Blue (+) and White w/ Green (-), which are pre-amp...but I got nothing. To be honest, I removed them w/o looking at which was negative and which was positive as I don't remember since they are cut RCA's . Would this have the affect of no signal or EXTREMELY weak signal?

If not, I took a few pics to show what I'm doing. Now that I keep looking, I think I might have taken the wrong ones...They were from the black connector all the way to the left in the picture. That right or no??


Wires I'm holding were taken from the black connector to the left




Edit: Yes I know it's nasty down there...I'm in the processes of cleaning it all up b/c the dumbass that had the car before me cut all the wires about 1" away from the connectors

 

Ok, I switched my PDX switch to 0.1-0.8v and it came on but it's WAY quieter than when I had them wired up post-amp. Not sure what the deal is. Doesn't hit hard, lows don't seem to be there...could it be out of phase??

 

Whoops..I thought I put this in my build thread..oh well. So I've got the gain 3/4 up and it sounds somewhat normal. Maybe a tad cleaner and that's why I'm thinking it sounds softer.

Still need help on wtf is up with my sound upon start up. Hiss can be heard after the initial sound goes away also. Think this might just be the dreaded PDX

 

I have no clue . But I believe the rca's has to do something wt hissing sound (weak signal?) . Sorry to hear that . I had that problem before .

 

How did you fix it??

I've got nice RCA's that are shielded, etc but I got the turn on noise on them too. FML

 

I had someone do the installation for me . But basically he ran and spliced speaker wires instead of rca cables to the LC8 (LOC) Then LC8's to the aftermarket amp with rca cables ....amp to speakers wt speaker wires .

I actually tried running rca's spliced from the stock amp and got that horrible hissing noise . I heard splicing rca cables is bad (forgot what they said why it was bad?)

^ someone clarify about splicing RCA'a . I cant remember

 

Are you deciding to keep the RK6's ? Im gonna keep mine till my setup is finished and decide from there .

 

Yeah, I wish some people would come in here and help if they have any clue. I think JDA spliced his RCA's and I'm assuming they sound okay. I'm sure other people have done it also. I'm just not sure what to do anymore...


No, I don't think I'm too fond of them. They are just a little too loud for me and the mids don't really starting punching until you turn them up...and by that time its just too loud. Just a bad x-over design is all that is. I heard they're fixing it with the new CK's. We'll see if I like the ID CXS's JDA is sending soon. If not, or even soon if my RK6's sell, I might buy some Hybrid Clarus/Imagine or Hertz HSK's.

 

I just spliced speaker wire into them but I'm going into a line driver which accepts speaker wire so I'm not much help. The best way seems to be to splice the RCAs right into the pre-amp signal though.
If you're going in that price range, you might as well include Dynaudio in your search. I've found a couple of the 2-way 242 sets fairly cheap plus Niebur3 can probably give you a good deal. Dyns are just awesome for what I want. They're not bright or dull, not muddy or punchy, they're just accurate and natural and incredibly detailed. The Dyns have revealed stuff in songs that I listen to almost daily that I never heard before. If you want them bright, you can eq them that way, if you want more midbass punch, it's just a little eq away. I've never had a set of speakers that were so responsive to eq. Midbass is fantastic. I had a few hours free and I wanted to go back and tidy up my install from a few months ago. I ended up playing them with the subs off for several hours and forgot just how good they sound by themselves.

 

I cut the heads off of RCAs, soldered and shrunk the connectors. Pre-amp all the way. I get white noise from my iSimple in the range of 1-2%, but none from the CD or Radio

Did you do your big 3? Ground is probably 75% of all noise issues.

The CXS are going out today. I dropped a LRx in there too so that you can see how different it is to run these things active, even if you don't have a processor... you can still control the crossover points and gains with just the amp.

 

Yeah I PM'd him awhile back to ask how much he could get Hybrid, etc for..I'll ask about the Dyn's.


Nice man thanks!! I'll get those tried out whenever I figure all this crap out. I don't want to harm the speakers or have a faulty signal while trying out stuff. I do know that I'm trying to sell the RK6's if anyone want's a nice/cheap set ($150+shipping or something).

 

I don't think it's your amp. I'm having the same issue with alt whine/noise from pre-factory amp splices into RCAs. Also, from the low voltage, having to turn the amp up considerably. Reworking the signal cables to remove the RCA heads (or just find some way to isolate them better) tomorrow. I used the ipod input direct method (into the amp) to confirm the amp was not my issue. If the above doesn't work and it is the balanced signal, my next approach will be taking post-factory amp signal (instead of a line driver) directly into my Zed amp. I'm trying to avoid LOCs and Ground Isos if possible.

As for the volume, I have my gain turned almost all the way and have yet to hit the clipping indicators on the amp so it's obvious the HU voltage is dropping considerably before reaching the amp so it is very weak. My dilemma is trying to understand if line driver/low gain has any advantage over low voltage signal/high gain without purchasing unnecessary equipment and modifying the install.

 

Get your big 3 done.

You always have to turn the gain up when you have a lower voltage input - this is what the gain does to normalize the input signal. 1 one the input and 8 on the gain is the same as 8 on the input and 1 on the gain.

 

Exactly. I think the power situation is the "pre-amp/post-amp" dilema, but I believe that's not what's causing the startup hiss, etc. I had the subs wired up post amp and they sound MUCH better (PDX on 1-8v setting and 1/2 gain). No way I can keep it this way as I'll run out of gain before I get to where I was at 1/2 with it post-amp. Line driver/Processor is a must if you want to do pre-amp I'm assuming.

I just want to figure out why I'm getting this nasty hiss. Maybe I'll take the RF and LF post-amp signals and see if it goes away instead of using pre-amp. It sounds like everyone that DOES NOT have a line-driver or processor is having problems but everyone that DOES have one is fine.


My buddy is awaiting my text for my subs and PDX for $700...about to just do it and sit back for awhile. Ugh..this sucks

 

The Zed will take up to 8v of input signal, but what the bottom number? The pre-amp signal is around 900mv.

If the amp has a low/high voltage switch, make sure that it is set correctly. For example, the JL Slash amps have low from .2 to 2 volts and high from .8 to 8 volts.

If the amp can accept a .9 volt signal, then I would get rid of the line driver.

 

Looks like the zed will go down to .25 volts, or 250mv. The 900mv signal should work fine without the line driver. Just set the gain to where approximately 900mv is and you should get the max out of the amp.

I love zed amps... one of the few amps with good bandpass filters. I think that they are cheap for what you get too.

 

Yeah, I'd definitely cut out that Line Driver. No need for it


JDA- any thoughts on my startup noises? It goes away when a certain amount of volume goes through the speakers. The subs act fine, the fronts don't. You think re-wiring the remote wire would be beneficial? Maybe take it to the comp. amp first..then to the sub amp

 

Yeah, didn't mean to hijack your thread TM. One of the reasons I picked the Zed up was due to the millivolt potential to grab pre-factory amp signals. However, even at max gain and max volume on the HU, clipping indicators STILL do not light up. Instructions on the Zed state to calibrate as such so that's why I am a bit puzzled and thought about using the line driver....to get the amp's best potential.

TM, in my research, it sounds like you are getting some feedback through the RCAs (hence why it's heard at only low volume). Someone on a different post said they were getting the same until they wrapped the RCA ends with electrical tape (just another thought).

 

Big 3. I don't know how power hungry the PDX amps are, or what kind of caps that they have, but they could really struggle to "charge" with a crappy ground from the engine to battery to ground.

I am not 100% certain that the big 3 will solve it, but it will eliminate the biggest suspect.

About 10 feet of 4 gauge and 6 ring connectors will get this done.

 

How does it sound at full gain and full volume? If it is cranking out the wattage, then what do the lights matter? Aren't those light for warning and not for tuning?

Line driver can cut your signal, or jack it up.