speakers

[soul searcher]

Does anyone know who makes a decent looking and sounding bookshelf speaker that is compatible with a car stereo or can you adapt a 8ohm speaker to work with a car stereo?

Thanx

Years ago, Radio Shack came out with a speaker called the "Minimus 7" It has since been sold to RCA, but is still sold at radio shack. These are inexpensive, decent sounding, rugged speakers. They are not water proof, but aside from that, they are good boat speakers. Very compact, and they work fine with a car stereo. I am sure the true audiophiles out there will have some other opinions, but for stand alone budget speakers, these work fine. I have 4 of them on my boat.

[Sandero]

I have 6 of them (radio shack) and they work well.

Jef
sv Shiva
Contest 36s

[Talbot]

I had the same problem and am working on the solution at the moment. I purchased 4 6" x 4" oval car speakers (JBL at £25 a pair) and am making a wooden box for each one out of 12mm plywood. Its not rocket science and the resultant box fits exactly where you want to use it.

[Alan Wheeler]

An 8ohm speaker will work on a car stereo, you just won't get as much "ooommph" from it.
There are a few 4ohm speakers in boxes as well. I will see who my supplier sells through in the US and let you know tomorrow.

[soul searcher]

Thank you guys,
I stopped by radio shack and asked about them and the kid there didnt seem to know what I was talking about so I checked on line at thier site and didnt see any thing there either. maybe they dont make them any more.
So it really wont hurt anything to hook up 8ohm speakers to a car stereo.
For the most part I don't care much for really loud music. I guess I'm officially too old

thanks again
Matt

[hellosailor]

Matt, if you don't mind spending a bit, BOSE makes bookshelf speakers that are actually water-resistant. A bit larger than the Minimus7 (which was replaced years ago by something newer) and a bit steeper in price, but designed to be installed where they would be rained on.

Depending on how many speakers you plan to install, a car stereo that was designed for four 4-ohm speakers will usually be quite happy driving two 8-ohm speakers, the total impedance is the same, you just shift the front/rear "balance" setting on the stereo for two speakers only. Some stereos will show you optional hookups to intentionally use only two speakers that way.

"the kid there didnt seem to know "
Radio Shack: "You've got questions? We've got blank stares!"

[soul searcher]

I dont mind spending a little more but I dont want to harm a brand new reciever either. I also have two weather resistant speakers in the cockpit(4ohm) the speakers that were in the salon were paradgrin they listed the impedence at four to eight ohms. I can,t understand why nobody makes a bookshelf four ohm speaker with all the fancy moter homes you see around.

Talbot, I thought about that also. But figured it cost the same by the time I got done, and being a victim of the immediate gratifacation society, I thught this would be quicker. Silly me


matt

matt, RCA, Cat#40-5001 8 ohms, 50w about $30 per speaker if I recall. 4"x4"x7", aluminum case. I tried building speaker boxes, and gave up because I could not get the sound quality in the size I wanted. I have purchased the Bose before, and they are far superior, but priced accordingly. Bang for the buck I stand by the RCA's.

[Alan Wheeler]

So you want some sound quality??? Polyplaner would be your way to go. They make a marine speaker for the "car stereo" type amplifier. They also produce Marine grade Head units as well.
GME is another, but I have not be a fan of the speaker sound quality.

No you won't hurt the amplifier by running on 8 instead of 4. And any speaker from 4 through to 8 wil be fine. As I said, you just don't get the same sound power output from the 8 as you do a 4.

As for the front/rear balance being shifted to compensate for two or four speakers, that doesn't work that way. It won't matter where you put that control. It has no affect on the loading the amplifier in the head unit "see's". the only way to have the correct loading using four 8 ohm speakers, is to wire them as pairs in parrellel. So you have two 8ohm boxes parrelleld together, equals a 4 ohm load. But that means you need four speakers total and it isn't neccesary.

[hellosailor]

"I can,t understand why nobody makes a bookshelf four ohm speaker with all the fancy moter homes you see around. " Easy. Because car stereos aren't designed for motorhomes, they are designed for cars. So the 4-ohm speakers are designed to be flush installed--not placed on bookshelves. You don't find many cars with bookshelves any more, and bog motorhomes will either have installed car stereos with high power and car speakers flushed in, or "real" stereos with higher-end speakers to match.

Wheels, I haven't looked at the schematics to see what the car stereos can do but was suggesting shifting the front/rear splitter to one side only, simply because that puts all the power from that circuit to "one" set of speakers. Some car stereos may use 4 discrete amps, others use just two and the front/rear control is just a splitter--so shifting it to just one side, provides "double" the power that is usually available, compensating for the 4/8 ohm difference to whatever extent it might be able to.

"As I said, you just don't get the same sound power output from the 8 as you do a 4." In theory! In practice? Aren't there 8-ohm speakers that are more than twice as efficient as some 4-ohm speakers? Speaker efficiency varies an awful lot, another rule of thumb where theory has to meet ugly reality. No? <G>

[Alan Wheeler]

OK, I understand your thoughts now. Most car units have 4 discreet amplifiers. It's how they can advertise that enormouse power output that actually isn't possible.

Yep, efficiency varies emensly. But efficiency is based on many very complex aspects and waaay to much info for describing here. But in simple terms, Car speakers are designed for particular installation. They have to fit into a cavity of varied size from open box to small box and yet perform the same and not distort or bottom out with the heavey bass they reproduce. They have to reproduce bass in a vibrating environment. So to do this, they are designed with very high "self dampning". This controlls the movement of the cone. But controling the movment of the cone also means they become inefficient.
4 ohm loading means that the amplifier can deliver the max amount of sound power into a load safely. Once again it's kinda so the add can say it is a gazzillion watts instead of a puny trillion watts. But they don't say how much distortion at those Gazzillion watts is being produced. It can be 10% or even greater in real measurements, once again, NOT what the numbers on the box say.

[GMac]

Wheels, you appearently knowledgeable stero chap.
What do you know about the Fusion gear we get down this way?
I need to replace mine on the boat and Fusion does have some sexy looking stuff.

Gezz... i'll learm 2 speel proper like one bay :-)

[Alan Wheeler]

Yeah well, I was at the top of the feild in the audio world at one stage. But big BIG stuff.
I view all Car stereo gear the same. It's full of specs that simply aren't "real". However, they are all dressed the same, so you can't really go tooo wrong. I see a lot of stuff on Trademe lately. I wonder who is selling it on there?

[GMac]

Fusion is Mr Navmans son, if you did not know.
So just get a good stereo and protect as much as possible from bad salty weather I suppose.

A lot of electronic boat stuff on Trademe is parrall imported. Knowing a few of the local guys it can have issues like set-up for the US or somewhere not here. International Warranties do not exist with 99% of the gear. Traders dissappear quick if too many problems catch up with them. Personally dramas like that I can't be bothered with. I supply a fair few of the local agents gear and I am far from shy when talking bribery and blackmail for goodies I want :-) so I can get good deals when required :-). One of the very very few good bits about owning a business here.