correct ohms for rear seat speaker

[Larry Minery]

I want to install a rear speaker in my 55 Roadmaster 76R. I have an NOS 10 ohm speaker (6X9 inch), but always thought car speakers were 8 ohm. Does anyone know for sure what is correct, 8, 10 or what. Thanks

[BRB62]

I believe 8-10 ohm is correct for Delco radio speakers. As long as it is not 4 ohm it should work correctly. turnswitch.com sells this size reproduction speakers as 8-10 ohm for this same application.

[Larry Minery]

BRB62: Thank you for your reply. I an inclined to think either 8 or 10 ohm will work. I will go with the 10 ohm unless I hear anything differently in the mean time. Larry

[NTX5467]

For some reason, Delco/GM used 10ohm speakers for their radios up into the later 1970s. I was concerned as I wanted to upgrade the speakers in my '77 Camaro and all I knew about were 8 and 4 ohm speakers from replacement manufacturers. Almost everybody I knew had put 8 ohm rear speakers in their GM cars for upgrades with the stock radio with no problems. All of the aftermarket radios were usually keyed for 4 ohm speakers, it seemed. I haven't looked to see what's out there in the range of 8 ohm speakers lately, though.

In one respect, I don't think the 8 ohm speakers would be an issue with the longevity of radio amps. I don't think that 4 ohms might be detrimental either. Still, my gut tells me that not venturing too far from the 10 ohm value might be good.

Just some thoughts,

NTX5467

[Larry Minery]

NTX5467: Thank you for your thoughts. As of now, I think I will install the 10 ohm in a day or so. By the way, the radio is a stock 1955 tube type radio that has been rebuilt and works well. Larry

[1957buickjim]

Larry, I think the correct speaker for your radio is a 4 ohm. I replaced mine with a 4 ohm, which is what is specified in the Delco radio info sheet for my 57 radio, which is a tube type like yours. I purchased it from a company named Electro-Tech in Blaine MN. The speaker was approx $40, less shipping. I had 10 ohm speakers in it prior to that (purchased from an auto parts store) and now having the 4 ohm in the car, the radio sounds better!

Just my 2 cents worth..

Jim

[Joseph P. Indusi]

I agree with 1957buickjim. Most tube type radios of the 1950's used 4 ohm speakers.

Joe, BCA 33493

[Larry Minery]

Thank you Jin & JPIndusi: You two are the only one's I have heard from that feel the 4 ohn speaker is correct & you both seem very sure of your selves, so I am going to put the 10 ohm back in the box & shop for a 4 ohm speaker. Thanks again for your input! Larry

[BRB62]

Larry, sorry for the false lead given earlier. Further research shows 4 ohm for valve type radios. I forgot that my Delco radio is transistorized and so has the 10 ohm speaker. You are correct to change speakers.

[Larry Minery]

Hey BRB62 no problem. I should have mentioned that the radio is a tube type in my first message. Thank you for replying back. Do you know a couple in Australia by the name of Ron & Beverly Noonan?? They traveled from Ca. to Flint with us to the 2003 Buick National, great people. Larry

[buick840]

Hey BRB62 no problem. I should have mentioned that the radio is a tube type in my first message. Thank you for replying back. Do you know a couple in Australia by the name of Ron & Beverly Noonan?? They traveled from Ca. to Flint with us to the 2003 Buick National, great people. Larry

Hi Larry,

Not may people in the Buick Clubs in Australia wouldn't know Ron & Bev,

we get to see them at nearly every Australian National Meet............Nice people.

[Larry Minery]

I finally found a 6 X 9 4 OHM rear seat speaker for my 55 76R and have it installed. It works great!!! Ah, the sound of low-fi, just like the good old days! Thanks to all for your suggestions. Larry

[JohnD1956]

Where did you find the 4 ohm speaker?

And can someone please explain this OHM concept in plain mans language for me?

[Larry Minery]

I bought the speaker at a vendor in So. Cal. (Danchuk Manufacturing 1955-1956-1957 Classic Chevy Parts) that only sells 55,56 & 57 Chev. Parts, but some chev. & Buick speakers are the same. A bit pricie, but they are only a few miles from me & I could pick it up. As for OHM's, it is a measurement of electrical resistance. resistance can be measured from almost zero OHN's to millions of ohms. For instance the voice coil of a 4 ohm speaker has very low ohms. Many other electronic parts have from low to very high resistance. All the bulbs in your cars have a resistance, usually lower. I think the last name of the guy that discovered this was Ohm. Larry

[1957buickjim]

Larry, I think the correct speaker for your radio is a 4 ohm. I replaced mine with a 4 ohm, which is what is specified in the Delco radio info sheet for my 57 radio, which is a tube type like yours. I purchased it from a company named Electro-Tech in Blaine MN. The speaker was approx $40, less shipping. I had 10 ohm speakers in it prior to that (purchased from an auto parts store) and now having the 4 ohm in the car, the radio sounds better!

Just my 2 cents worth..

Jim

JohnD,

This is another place to get the speakers. Just google the company name and it will come up. All they do are factory correct replacement speakers. I looked at my old roasted speaker and noticed it was 4 ohm, so I figured I should replace it with the same type. Larry is correct about ohms and resistane. It was a physicist named Ohm who came up with Ohm's Law. Here is a link to a site to understand it if you want. Ohm's Law.

Good luck!

Jim