While I have the dash out of the 77 for heater core, steering column and brake booster replacements, I wish to replace the OE dash speakers with something a bit more modern (read not blown yet). I will be driving them with an original Delco stereo radio so I don't need audiophile quality plus I'm too deaf to appreciate fine tonal nuances any more. Anyone have a favorite "bolt in" set that won't break the bank? Thanks!

 

Im going with Pioneer 4X6s.

 

What do you have for a radio, the original requires 10 ohm speakers.

 

Factory Delco push button AM/FM. I seldom turn the radio on when I'm behind the wheel but SWMBO (She Who Must Be Obeyed) will be a co-pilot and tunes are a must have. Will a 4 or 8 ohm load kill the factory output transistors??????

 

You need low wattage, 8 ohm, 4x6" speakers. Something less than 50 watts (25-30 would be better). 8 ohm speaker impedence will not endanger the output amp stage on the Delco radio. It may cause some distortion, if you crank it up most/all of the way on volume.

4 ohm speakers are more common. And you can use them, IF you put some additional speakers behind the kickpanel areas and wire them in series with the dash speakers on each side. 4 ohm + 4 ohm = 8 ohm total impedence. Plus, with the larger mid/bass speakers in the kickpanel area and the hi frequencies coming from the dash speakers (reflecting off windshield), you will have a much richer and full sounding speaker set. That's what I did with mine, and I'm very happy with the results.

 

7t1 may I ask specifically what you used? I am passingly familiar with parallel/series wiring to achieve the desired impedance, but have been out of touch with component technology for many years. As an example, my home stereo is powered by an Adcom GFA500 200WPC discrete amp which I purchased somewhere around 1985 (???) and is powering a set of Infinity Crescendo Series towers which replaced the Bose 601s that finally gave up the ghost in the late 90s.

 

Classic Car Speakers has some proper 10 ohm speakers for about $80. I found them on the internet or you can do a search on Google. Look for S&M Electro Tech.

 

Thanks gents!

 

Given what you are looking for, check your local Wally Mart. You'd be surprised what you can find there sometimes. I picked up a set of Sony 4x6 4 ways for under $50. Had to drill the speakers mounting holes a little (on the speakers), but they fit well and were shallow enough to fit well in the dash.

Adam

 

http://www.turnswitch.com/speakers.htm


Towards the bottom;

 

You really don't want those copies of the original speakers that are 10 ohms. First, the original speakers weren't all that good. Secondly, modern speakers are much better in quality and performance.

I bought my speakers from onlinecarstereo.com . They had several 4"x6" speakers that will work. The dash speakers in the Corvette are fitted to a metal frame that then mounts to the underside of the dash. You want to reuse those frames; otherwise, the weight of the speakers may just cause them to detach from the dash pad.

The new speakers may have a plastic frame with many different hole sets. Even so, your frame bolts may not match up to any of them. If that's the case, you can use a pencil-type soldering iron to burn some holes in the right places so they fit the frames well. It's no big deal to do that. (You can use a drill, too...but the soldering iron was handy.)
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Suggested speakers from onlinestereo.com :

4"x6" 4 ohm Kenwood KFC-4675C $43 each (on sale now) [these look really good to me for dash speakers]

4"x10" 4 ohm Kicker 05KS410 $45 each (on sale now) [these are the correct size for the area behind the kickpanels]

Note: If you decide to put two speakers on each side, send me a PM and I will walk you through the [simple] hookup.

 

If you are using the original head unit, the link that I posted is EXACTLY what you want!

 

Adam... are those Sonys 4 or 8 ohm impedance??? Mashman... thanks for that link. As I price 4 4-ohm speakers to wire as 7T1 recommends those look like a better deal. How do they sound??????

 

I'll apologize for being disagreeable up front...

But, I looked at that website Mashman listed, and I don't like the looks of those "rebuilt originals". They use an antiquated magnet technology that yields a lot of distortion with little power put to them. Modern design speakers with modern magnet technology and polymer speaker cones are much more responsive and provide much better sound quality than the old AlNiCo magnets and paper cones.

Just sayin'....

 

Go with the Infinity line of reference speakers....they are the best for two reasons:

First, they utilize the cars original wiring for better impedance matching.

Second, the mounting depth is less than 2" which will not interfere with the dash pad upon installation.

http://www.ebay.ca/itm/NEW-INFINITY-...ht_3441wt_1010

 

Just a caution... I tried to install the Infinity's in my 1980 and had two issues. 1) The speaker's are fairly deep, so I couldn't get the passenger side one to sit down far enough without hitting the top of the glove box. 2) The black plastic edging around the speakers are also fail thick, which wouldn't allow the speaker covers to sit properly over top.

I'm currently looking for speakers with a flat metal speaker surround and are also low profile for a correct fit.

This may not be an issue for you, but though you might just want to fully check out the sizing before moving forward.

-Stephen

 

Briankeery... those Infinities confuse me as the listing states both that their impedance is 2 ohm, and they also have "true 4 ohm" capability... WTF is that supposed to mean??? A 10 ohm rated amp will not drive either a 2 or 4 ohm load very well, or for very long. Remember I'm using an original Delco redio here complete with oddball 10 ohm output impedance. Stclarke... thanks for the heads up but there is no glovebox in a 1977 so depth is less an issue.

 

Four ohm speakers will pull twice the amperage through your stereo, and it will melt.

I contacted Jerry at www.electrodesign.us about rebuilding my original stereo, and his recommendation for speakers was the following -

Greg Thompson is at http://www.turnswitch.com/ - and his speakers will handle anything your original stereo can put out, and more - plus they have the added benefit of not melting your stereo.

 

8 ohm speakers....or two 4 ohm speakers wired in series...are fine when matched with the Delco 10 ohm amp output. Will the speakers draw a bit more current? Yes. Will it present a risk to the radio/amp unit? No.

Placing only one 4 ohm speaker on the Delco set will be fine...as long as the volume **** isn't turned past about 50% volume setting. After that, it's just a matter of "when" the amp burns up. And, no, it won't catch on fire; it will just destroy the transistors that generate that power. Then, you won't hear anything.

Placing a 2 ohm speaker on that Delco head will yield a transistor failure almost immediately.

Also, the modern "reference" speakers are intended to be matched with a high-power amplifier....which the Delco is NOT. At best, it provided 16 watts RMS power to the output. High fidelity "reference" speakers are, by design, very inefficient...meaning that the speaker takes an excessive amount of power to operate it (compared to the sound power that is produced). The benefit of running such a speaker is that the sound QUALITY is exceedingly good.

So, if you have a Delco unit in your car, you MUST install relatively efficient speakers, or you will have little sound power actually produced. Sticking 400watt-capable speakers on a Delco head is like sticking M/T 16" wide drag slicks on a 40 hp Volkswagen. It just doesn't work. 20-40W speakers will work much better with the Delco unit.

Buy what you want; connect what you will. But sound systems have some basic fundamentals that must be followed, if you want decent sound and also wish the system to operate well for a long period of time.

 

I hear you loud and clear 7T1; if you read my posts carefully you will see we are on the same page about impedance/power requirements and such. I also understand the difference between series and parallel wiring for impedance stacking, and how to wire each way. BTW, Mashman's recommended fitment utilizes Neodimium magnets, rubber outer rims on the cones and a composite cone... they are a relatively modern iteration produced to appear quite similar to original. Finding a pair of suitable replacements has proven to be a bit more daunting than I had anticipated... more research is in order and I'll let everyone know where I end up. Thanks to all who took the time to respond here!