By Bob Cannon
The original round speaker size for the T6 cars was about 5 inches in diameter; current speakers come in 5 1/4 inch diameters, which fit well, but may require that the mounting tabs be trimmed to fit within the speaker grills. The major problem you will face is the overwhelming number of choices available and picking the "best" set for our 1960 versions of a radio.
If you are using your original radio, you should choose replacement speakers with high efficiency ratings since the output of these radios is much less than modern units. Efficiency is generally measured in decibels per watt at one meter, or dB/Wm. With an input of a single watt, a speaker with a sensitivity of 90 dB/Wm will produce 90 decibels (dB) of sound at a one-meter distance. Most ìhighly efficient speakers have dB ratings of 91 or above and a speaker rated 3 dB higher than another will require half as much power to produce the same output.
Minimum power ratings on speakers provide you with another rough guide of the expected output from our low-powered radios, which may not be able to drive less efficient speakers without causing distortion. In general, you should look for speakers with minimum RMS power ratings of 2-5 watts. dB ratings and minimum RMS power ratings are less important if you have changed your radio to a modern unit with outputs of 15+ watts/channel, but need to be considered when using a 40 year old Blaupunkt. For additional information, an excellent discussion of the factors to consider when choosing speakers can be found on the Crutchfield website. The impedance of most currently available speakers is 4 Ohms, which is correct for the old 6-volt radios.
There are a number of 5 1/4" speakers currently available which appear to satisfy the criteria of high efficiency and low minimum RMS power requirements, in all price categories. On line retailers such as Crutchfield are good sources to learn about what is available; many of the same speakers may be available at your local audio supply or electronics store as well. I have listed a few 5 1/4" speakers that you might consider, based on their ratings; your wallet and personal listening preferences may favor one brand/model over another.
|Speaker||dB||RMS power range (Watts)|
These speakers range in price from $39 to $89/pair, although you may be able to find them discounted at some retailers. I am currently running a set on the Pioneer TS-G1340R in my Cab which were purchased at a local Walmart for $39/pair. They sound great. I would be interested in the feedback from others regarding their choices.
[Editor's note: NLA Parts offers excellent reproductions of chrome trim rings and speaker grills for T2, T5, and T6 cars, as well as speakers.]