Vintage car radio to amp

[PaulR]

I was lucky as the Rover has a lot of space behind the dashboard so I could build a box in which to fit the radio. The idea of using an ice cream tub or similar to see whether there was any improvement came to me because I once removed the speakers from a scrapped electric organ and those that didn't have much baffle were enclosed in a sort of pudding bowl, presumably to act as a sort of infinite baffle.

The combination of a better speaker and some sort of enclosure may well help. As you say, the engine noise in these old cars is rather a hindrance. We forget how quiet modern cars are inside in comparison.

[tri-comp]

It seems to me that the correct manual for your Hildesheim, at least according to the picture of the radio, is this one:
https://nvhrbiblio.nl/schema/Blaupunkt_7639000.pdf
Unfortunately not made by the factory for use with external amplifier.
It does, however sport a reasonably powerfull amplifier section itself using complementary Germanium output transistors AD161/AD162.
They will usually provide about 4~6 Watt output with a 12V supply voltage, more than enough if connected with a quality speaker in a suitable enclosure.
A suitable enclosure is not an open baffle as the one shown. Bass will be next to none existent imho.
You could do an experiment and connect the radio to a small hifi-speaker in a closed or bass-reflex cabinet. That should give you an idea about what the radio is capable of. If you find it to be OK, and even though AM stations are nowhere near the quality of FM and DAB, the sound is original and vintage to go with the car.
Next will then be to replicate that sound quality into the baffle setup. Not an easy project!

Rgds,

/Torben

[MGBGT1966]

Originally Posted by Edward Huggins

There seems to be room in that original fibreboard speaker enclosure for a larger speaker.

Car Scrappers/Breakers will usually have many 9" x 6", 4 ohm units which is a popular auto size. These are liable to have a roll surround to the cone for an improved Bass. If there is a concentric tweeter, this could be disconnected/removed to achieve a more "mellow" sound.

Thanks Edward, I will keep this in mind. Indeed, car scarppers (or craigslist) seem like good options.

[MGBGT1966]

Originally Posted by PaulR

I was lucky as the Rover has a lot of space behind the dashboard so I could build a box in which to fit the radio. The idea of using an ice cream tub or similar to see whether there was any improvement came to me because I once removed the speakers from a scrapped electric organ and those that didn't have much baffle were enclosed in a sort of pudding bowl, presumably to act as a sort of infinite baffle.

The combination of a better speaker and some sort of enclosure may well help. As you say, the engine noise in these old cars is rather a hindrance. We forget how quiet modern cars are inside in comparison.

Interesting indeed. I have tried searching the net, but I havent found any descriptions on building a box for the front console of the mgb. There are plenty of detailed descriptions for installations in other parts of the car though and the engine noise is always a culprit. I might take this box-thing further once I get access to the car. Thanks for the tips

[MGBGT1966]

Originally Posted by tri-comp

It seems to me that the correct manual for your Hildesheim, at least according to the picture of the radio, is this one:
https://nvhrbiblio.nl/schema/Blaupunkt_7639000.pdf
Unfortunately not made by the factory for use with external amplifier.
It does, however sport a reasonably powerfull amplifier section itself using complementary Germanium output transistors AD161/AD162.
They will usually provide about 4~6 Watt output with a 12V supply voltage, more than enough if connected with a quality speaker in a suitable enclosure.
A suitable enclosure is not an open baffle as the one shown. Bass will be next to none existent imho.
You could do an experiment and connect the radio to a small hifi-speaker in a closed or bass-reflex cabinet. That should give you an idea about what the radio is capable of. If you find it to be OK, and even though AM stations are nowhere near the quality of FM and DAB, the sound is original and vintage to go with the car.
Next will then be to replicate that sound quality into the baffle setup. Not an easy project!

Rgds,

/Torben

Thanks alot Torben, that sounds promising. I am leaning towards building a box to surround the speaker. I dont know yet how much space there is behind the baffle, only that it will be limited. How big of a box do you think I would need to house a 4X7 speaker, or a 6x9 speaker respectively? Also, I am not sure what type of enclosure that would be most suited (closed, bass reflex). Ideally, the solution should be compact. Any suggestions would be welcome. Thanks, Gunnar