I hope you don't mind that I resuscitated this three year old thread.
I have a Frazier Symphonetta that I acquired around 25 years ago but I never bothered to research it online until today.
There is no evidence that it ever had a metal tag and there is no serial number. It only has a paper tag identifying it as a Symphonetta.
It appears to have the same mahogany veneer and does have fiberglass insulation in the ports like the original poster's doghouse speaker. It also has a volume pot as shown in the photos.
