Audio Systems: car radio reverbration unit(s), reverb units, digital reverb

Question
On the previous page, someone mentions the reverbration units of the sixties.  I had one of those Motorola units and did not keep it when I sold the car as I did not know they would become extinct.  Now I would like to have one again.  Any ideas on how or where to purchase one, either from the sixties (used) or who makes them today??  Thank you in advance for your help, and I have spent hours on line but do not understand much of the electronic jabber used in their descriptions.

Answer
The Vibrasonic was made for cars back in the 60s.  I think they were popular on some Ford models.  You can find them occasionally on eBay and other auction sites but I don't think this company is in business any more.  There is another product called Vibrosonic which was used with guitars.

The reverb was produced by a mechanical spring and a pickup on the other end; then fed back into the audio amp again.  They had a very interesting sound effect.

Now days all reverb units are electronic and use digital circuits to delay the digitized audio then convert it back to analog.  They are much higher audio fidelity and are available in all sorts of products.  However, I don't know of any made just for car or mobile use.

Most of the ones commercially available now days are for music applications such as this one:

http://www.bhphotovideo.com/c/product/605979-REG/Behringer_DR600_DR600_Digital_R...

You can google for others.  

It may be possible to find one that is battery operated and wire it up in your car system; if you have separate power amp feeding the loudspeakers the reverb could go between the head unit and the power amp.  

Best wishes.