Stereo's 101 for DUMMIES

[rpaxton]

Depends on a couple of unknowns here, what subs do you have and are they single voice coils or dual voice coils. If DVC's, what impedance are the coils? And what amp do you have? If you dont have the amp yet, knowing the specs on the subs will help you choose the right amp.

OOOPs!! My bad.

I am running two Polk MM1040UM ten inch subs. They are dual voice coils, 4 ohms, 350 watt rms and 700 max. I went with the Alpine PDX-1.600M amp on a recomendation from a friend. Currently the speakers are both wired into the single plug in parallel (I think - both positives are in the positive side and the negatives are both twisted together in the negative side). This gives me enough thump to vibrate the entrie boat, but I want to make sure that I don't damage any of the equipment.

This is one of my first true stereo builds and was done on a budget. I would have preferred wetsounds equipment, but......



Rodg

[chpthril]

Hey Phil,

I have two 10 inch subs that I want to power with a single channel mono amp. should I wire them in parallel or seriel?

Thanks in advance,

Rodg

Depends on a couple of unknowns here, what subs do you have and are they single voice coils or dual voice coils. If DVC's, what impedance are the coils? And what amp do you have? If you dont have the amp yet, knowing the specs on the subs will help you choose the right amp.

[rpaxton]

Hey Phil,

I have two 10 inch subs that I want to power with a single channel mono amp. should I wire them in parallel or seriel?

Thanks in advance,

Rodg

[Thomas Hohl]

These guys made my install a piece of cake (well relatively speaking) and it absolutely ROCKS!!!

So listen up!!!

[chpthril]

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.

[philwsailz]

A simple basic understanding can be achieved if you follow these basic rules:

For amps and speakers totally DISREGARD peak power ratings, and specs. Those are created by marketing, not engineering. we also call them WLS specs; i.e. When Lightning Strikes specs.

Try to find the CEA2006 power output spec for any amp. That power output is an industry standard, designed to give you a clear indication of what an amp will put into a single 4-ohm speaker. When you connect two speakers to that same amp channel, the power output increases, (sometimes doubles) giving you close to that same power, ( the 4-ohm CEA2006 spec'd power) into each speaker. Usually it is a little less though. For example a 2-ohm stable KICKER MX350.4 amp will deliver 90 watts into a 2-ohm load; two 4-ohm speakers in parallel as an example. IF you use a single 4-ohm speaker, you will deliver about 65 watts to that speaker.

A speaker on a slightly more powerful amp than designed for will last longer than a grossly underpowered speaker on a smaller amp.

There is no way to wire a single amp channel to operate at 2-ohms with a single 4-ohm speaker. The speaker presents the load to the amp, not vice - versa; the amp has nothing to do with it. If you have a single 4-ohm speaker on an amp channel, you will get that amp's 4-ohm output.

It is always best to purchase amps and speakers at the same time. Do your shopping based on CEA2006 amp output, and RMS speaker power handling. Pick the speakers you like, then pick an amp that has the RMS power output to match RMS speaker power handling. If you cannot find an amp at exactly the same RMS output as the speakers power handling, buy the next larger amp, not the next smaller amp.

Try to always buy as many amp channels as you buy speakers. Just because an amp is 2-ohm stable, is no reason to force your amp to operate into that load. If you have one amp channel for each 4-ohm speaker, the amp(s) will run cooler, run longer, sound better, and cause you less headaches. The exception will be subwoofers; digital subwoofer amps have less of an issue with being run at their rated impedance.


In your example, your 65 watt RMS speaker wired to a single amp channel can only get 45 watts.

For your last question, if you want to operate a 150 watt 4-ohm speaker with this amp, you will bridge a pair to get 150 watts. You can drive 3 speakers this way.

Zat help with the understanding? If not no problem, post up your questions, and I will try to answer. Tim at Wetsounds and Chpthril will have insight maybe too; they are both very knowledgeable.

Good luck and have fun!

Phil
Kicker

[yllw20]

always overpower your speaker than underpower.
-

[dogbert]

I'd PM philsailz or read his posts. He works for Kicker and has really supported us well when it comes to wiring stereos for our boats. Other guys who have contributed a lot have been chpthril & wetsounds1. Look for their posts and you will learn more about stereos and be able to put your own system in with no trouble. There are several 101 type threads already posted. Use the search feature

[HippoBoatamus]

I have never had any kind of stereo like what my new to me Tige has, and I am certainly not a stereo guy. So my efforts of reading both on the web in general and on this site I think are starting to make since. So I am asking here to make sure I understand before I waste any money.

My tower speakers are crackling and sound like crap, and will cut out from time to time. My amp is not hot by any means, so I am assuming it is the 2005 model speakers up there that are all rotted out and crap....

I have three amps, but the one pushing the tower speakers is this one. http://www.sonicelectronix.com/item_...e+Series-.html

It shows in the specs this....
RMS Power Output:
45 Watts x 6 Channels @ 4 Ohms
75 Watts x 6 Channels @ 2 Ohms
90 Watts x 3 Channels @ 8 Ohms (Bridged)
150 Watts x 3 Channels @ 4 Ohms (Bridged)

I know the difference between Peak and RMS, and 2 and 4 ohms now, but my question is that I am finding speakers with Peak anywhere from 300W - 500W, but RMS rated at 65W. My amp has one channel each to the tower speakers wired at 2ohms, so it is pushing 75W to each channel. (that is my guess based on specs)

Can I hook up a speaker with a 65W RMS max to these channels and just turn the gain down a little so as not to push the max 75W RMS? Is the extra 10W not enought to worry about? Is the extra 10W covered in the up to 300/500W max? Or of course, am I way off target and not understanding any of it?

What if I find some speakers rated 600W max and say 150W RMS, I don't have near enough RMS power for something like this in this configuration? I would have to wire up the two channels at 4ohms to get the 150W RMS max right?