Stereo's 101 for DUMMIES

[chpthril]

Ok, Bass and treble on the H/U, turn both to "0". "Loudness" off, and "sub volume" all the way up. Now, if you are having to add more then a click or 2 of bass at the head unit to get the thump you want, then you maybe need to go back to the amp and check the x-over setting, what's it set on. Try about 50hz's. The other thing is that those may not be a "free-air" (infinite baffle) sub. The lack of an enclosure will have an effect on the output

Not too familiar with the Alpine stuff.....guess I need to, now that i'm officially a dealer for them now.

[rpaxton]

He he he he!

Sorry Chp I did get your email, just wasn't looking for your real name... OOOppppss!

I will take a look at those tonight and let you know. Right now I am about to go load the boat and run out to the lake for a few sets!

On the amp, that is what I did. Zeroed out all of the bass and set my cross overs and gain. The Alpine stereo unit has a bass/treble, loudness, and a "sub volume" control. I think that I can purchase a seperate sub control for this unit, not sure though, but obviously I dont have that installed right now. When I turn up the bass and sub volume controls is when it plays for a few minutes then shuts down (glow turns from a pretty blue to an ugly red!)

I may have to call Alpine tech support to figure this one out.......

On another note, do you know of anyone who has built their own boat tower??

[chpthril]

Hey Chp,

One more question about stereo amps. The two subs are connected to an Alpine pdx-1.600m mono amp. The other day I noticed that when I really cranked up the base the amp played for a few minutes then shut down (due to being overheated is my guess). Do I have an amp problem or am I trying to push too much with too little amp?

Also, don't forget you were going to get me some info on LED courtsey lights.

Thanks

Rodg

When you say "when I really cranked up the base", are you using the bass on the head unit? If so, then that could be the cause. The best thing to do is set the amp up correctly i.e gain and x-over frequency (in Hz's), with the head units EQ zero'd out, flat. Then use the H/U's treble and bass controls mildly to fine tune the sound to your liking. Does the amp have a remote bass control knob?

I email that to ya on Fri, did ya not get it? I check to make sure it went and didnt bounce back. I'll copy/paste it to a PM.

[rpaxton]

Hey Chp,

One more question about stereo amps. The two subs are connected to an Alpine pdx-1.600m mono amp. The other day I noticed that when I really cranked up the base the amp played for a few minutes then shut down (due to being overheated is my guess). Do I have an amp problem or am I trying to push too much with too little amp?

Also, don't forget you were going to get me some info on LED courtsey lights.

Thanks

Rodg

[rpaxton]

There is no real pro or con, it has to do with flexibility. For either Single or dual voice coils, you still have to purchase the speaker with the total number of speakers in mind, the amp in mind, and then make the determination which impedance you need to go with.

In your situation, the 4-ohm speaker is the proper choice, so someone did it right. Think of a single voice-coil, 4-ohm speaker as a dual 2-ohm speaker, wired in series... The woofers were chosen with the knowledge that that amp was 2-ohms stable so it is a good configuration; leave it the way it is; you will not damage anything. You are putting 300 watts RMS into a 350 watt speaker. You could do a little more, but what you have is not bad.

There is no way to wire the subs differently to get more power out of the amp.

I say, if it rattles the boat you are good to go!

Phil

Then I will leave it as it is! I was the one making the purchases, I guess I just got lucky; especially with my limited knowledge of ohms. Thanks for all of the advice guys! Now I just need to mount this MC10 remote somewhere by the driver's seat (hopefully this one will not burn its self out).........

[philwsailz]

There is no real pro or con, it has to do with flexibility. For either Single or dual voice coils, you still have to purchase the speaker with the total number of speakers in mind, the amp in mind, and then make the determination which impedance you need to go with.

In your situation, the 4-ohm speaker is the proper choice, so someone did it right. Think of a single voice-coil, 4-ohm speaker as a dual 2-ohm speaker, wired in series... The woofers were chosen with the knowledge that that amp was 2-ohms stable so it is a good configuration; leave it the way it is; you will not damage anything. You are putting 300 watts RMS into a 350 watt speaker. You could do a little more, but what you have is not bad.

There is no way to wire the subs differently to get more power out of the amp.

I say, if it rattles the boat you are good to go!

Phil

[chpthril]

Okay,

I checked Polk's website which is now working correctly, but was not when I made this purchase. apparently I do have the single voice coils instead of the dual that I wanted. How much of a difference do the DVC make??

R

I will let Phil describe the pro's/con's of DVC and SVC subs, but in your case, it will make no difference on the output of the amp, so each sup will be getting 300 watts rms each. Your 2 4ohm subs will be wired in parallel so the amp "sees" a 2ohm load. Now, I may need to double check, but the SVC subs may have a lower RMS requirement. If so, this would move you from the slightly under powered side to the slightly over powered side, which is a good thing.

[rpaxton]

Okay,

I checked Polk's website which is now working correctly, but was not when I made this purchase. apparently I do have the single voice coils instead of the dual that I wanted. How much of a difference do the DVC make??

R

[chpthril]

Sweet!

That is how I have them wired currently, however my speakers do not have two positive and negative terminal connections on them (only one set of pos and neg). I suspect that Polk wired the voice coils together and only has one set of terminals for each speaker. Or did I get the wrong subs and these are only single coil?????

Thanks for all of your help!!! Your explinations really do rock!

That sounds like single voice coil subs. I wouldnt call them "the wrong subs" just, If they are 4ohm svc subs, wire the parallel (+ to +, - to -) and that will give you a 2 ohm load on the amp, which is perfect!

[rpaxton]

Ok, so the 2 subs are sharing the same space behind them, correct? If so, you will see a world of improvement just by separating them. Basically, giving each sub it's own enclosure of proper size, on the back side.

Speaker = sub, they are the same thing basically when talking load and wiring. Look at it this way, each sub has 2 separately wired voice coils, kinda like 2 speakers in 1 sub. Each individual coil has a 4 ohms impedance (resistance). So, each sub can be wire either in parallel or series to end up with a different load. when 2 loads are wired in parallel, it halves the impedance, when 2 loads are wired in series, it doubles the impedance.

The "load" (speaker impedance) that is placed on the amp, what it "sees", determines the output, typically. So, two 4ohm coils wired in parallel = a 2ohm speaker, when wired in series with another 2 ohm speaker, it will = 4 ohm. Or, take 2 4ohm coils and wire them in series = 8ohm. Wire it with another in parallel, it = 4ohm. Here's an illustration I borrowed from the12volt.com

Sweet!

That is how I have them wired currently, however my speakers do not have two positive and negative terminal connections on them (only one set of pos and neg). I suspect that Polk wired the voice coils together and only has one set of terminals for each speaker. Or did I get the wrong subs and these are only single coil?????

Thanks for all of your help!!! Your explinations really do rock!

[philwsailz]

Chp is on the case.

Good explanation as usual...

The two subs are both mounted under the dash board. I dont have them in boxes yet they are "free air" right now. They hit pretty hard as it is, but I want to put them in boxes.

As far as the wiring you lost me going from wiring the speakers in parallel and the subs in seriel (or vice versa). How is that accomplished? Also, I thought that if a speaker was rated at 4 ohms it needed to stay at 4 ohms to keep from damaging it, is that not correct?

Rodg

Ok, so the 2 subs are sharing the same space behind them, correct? If so, you will see a world of improvement just by separating them. Basically, giving each sub it's own enclosure of proper size, on the back side.

Speaker = sub, they are the same thing basically when talking load and wiring. Look at it this way, each sub has 2 separately wired voice coils, kinda like 2 speakers in 1 sub. Each individual coil has a 4 ohms impedance (resistance). So, each sub can be wire either in parallel or series to end up with a different load. when 2 loads are wired in parallel, it halves the impedance, when 2 loads are wired in series, it doubles the impedance.

The "load" (speaker impedance) that is placed on the amp, what it "sees", determines the output, typically. So, two 4ohm coils wired in parallel = a 2ohm speaker, when wired in series with another 2 ohm speaker, it will = 4 ohm. Or, take 2 4ohm coils and wire them in series = 8ohm. Wire it with another in parallel, it = 4ohm. Here's an illustration I borrowed from the12volt.com

[chpthril]

The two subs are both mounted under the dash board. I dont have them in boxes yet they are "free air" right now. They hit pretty hard as it is, but I want to put them in boxes.

As far as the wiring you lost me going from wiring the speakers in parallel and the subs in series (or vice versa). How is that accomplished? Also, I thought that if a speaker was rated at 4 ohms it needed to stay at 4 ohms to keep from damaging it, is that not correct?

Rodg

Ok, so the 2 subs are sharing the same space behind them, correct? If so, you will see a world of improvement just by separating them. Basically, giving each sub it's own enclosure of proper size, on the back side.

Speaker = sub, they are the same thing basically when talking load and wiring. Look at it this way, each sub has 2 separately wired voice coils, kinda like 2 speakers in 1 sub. Each individual coil has a 4 ohms impedance (resistance). So, each sub can be wire either in parallel or series to end up with a different load. when 2 loads are wired in parallel, it halves the impedance, when 2 loads are wired in series, it doubles the impedance.

The "load" (speaker impedance) that is placed on the amp, what it "sees", determines the output, typically. So, two 4ohm coils wired in parallel = a 2ohm speaker, when wired in series with another 2 ohm speaker, it will = 4 ohm. Or, take 2 4ohm coils and wire them in series = 8ohm. Wire it with another in parallel, it = 4ohm. Here's an illustration I borrowed from the12volt.com

[HippoBoatamus]

Great explanation from Phil as usual


What are you looking to do? address the crackling speakers by making sure what you have is wire and set right, upgrade to new tower speakers and possible amp, replace the speakers in existing enclosures (cans)? How many tower speakers do you have on the tower now and what kind are they (mainly the speaker themselves). Sorry if I over looked, the $$$ are blurring my vision ?

Lots of ways you can go, and end up with a nice sounding, properly operating setup.

Ok, so I took all my newfound knowledge and crawled my butt into the storage area. I cut all the zip ties, labeled all the wires, and disconnected everything form the amps, except for my sub. It is on it's own amp and working well.

I plug in wires one at a time and have my kids tell me what speaker came on . I then re-label the wire with what speaker it is, and disconnect. In a few mins, I know what wire goes to what speaker.

Next I put four of my cabin speakers on my Clarion APX 480M. Two speakers in each channel. I adjust the gain for my sub and cabin speakers with volume one notch down from MAX, and it sounds good!
Man this is fun!

I then plug my two rear cabin speakers into one channel on my e6450 so they get alot more power than the other four. Radio back on, I adjust the gain for the channel that the two rear cabins are on, sounds even better!
I think I love this radio thing!

Now I disconnect the power cables for the Clarion amp, sub amp, and pull wires out of the e6450 for the rear cabins. I don't want to hear anything else while I am trying to fix the issue with my tower speakers.

I put my two tower speakers in the e6450M. One channel each. Radio comes on, and the crackling is gone! Man I ROCK! Then I hear a snap, crackle, pop, and the right tower speaker blows.
Man now this radio thing SUCKS! LOL

I then realized that I have no idea what speakers are in the tower cans. So for all I know I just put 150W to a 65W speaker. So I turn the gain way down so the Left speaker is putting out some tunes. I plug it all in and I can live with this for the time being.

Now I am saving for some WS 60's.

[rpaxton]

The two subs are both mounted under the dash board. I dont have them in boxes yet they are "free air" right now. They hit pretty hard as it is, but I want to put them in boxes.

As far as the wiring you lost me going from wiring the speakers in parallel and the subs in seriel (or vice versa). How is that accomplished? Also, I thought that if a speaker was rated at 4 ohms it needed to stay at 4 ohms to keep from damaging it, is that not correct?

Rodg

[chpthril]

Ok, looking at the specs and owners manual for that amp, I dont see a 1ohm spec, so my gut says it's only stable down to 2ohms, which is normal. This amp will deliver 600 watts rms at both 2 and 4 ohm loads, that would net you 300W's to each sub. A little light, but not bad.

With 2 4ohm DVC subs, you're only gonna get a 1ohm or 4 ohm load at the amp. Since the amp looks to only be stable at 2 and 4 ohms, you will need to wire them in such a way to get that 4 ohms. There's 2 ways o do it: Wire each sub coil in parallel, that = 2 2ohm speakers. Then wire the 2 subs in series to = 4ohm. Or, wire each sub in series, which = 2 8ohm speakers, then wire them together in parallel to = 4ohms at the amp.

Are these 2 subs going to share an enclosure, or be in seperate parts of the boat?