I started collecting/accumulating DeArmond and Martin amps about 15 years ago. That was before the prices got so high. It all started with the little single ended versions, the R10 and R10T, which are little screamers. The single 12" models with 2 6V6 power tubes are very cool too, followed by the 2 6L6 R25T amps. I currently have 5 Martins, 3 with tremelo and 2 without. I had a 6th Martin that I purchased off of ebay several years ago. I sold it to a friend and eventually bought it back. Sometime later I sold it to another friend of mine with the understanding that he had to give me first crack at buying it back.
I also have about a half dozen of the baby DeArmonds. The Martin 110 amp that recently sold on ebay was the only one of those that I have ever seen or heard of. The other recent ebay auction for the R25 amp with the single 12" speaker was only the 3rd one of those that I've heard of or seen. I have 3 of the R25T amps with the standard 2 10" speaker configuration. I also have about a half dozen of the 2 6V6 amps.
I havent' gone through all of the amps to catalog the little details, however, I did pick through 4 of the Martins a few weeks ago to check out the transfomer information.
Here is the model, serial number and transformer information I collected off of those 4 amps:
Model: 112T
Serial No. MC2-1301
Power Transformer: PT-5201 549-6045
Output Transformer: T-703 549-6050
Model: 112T
Serial No. MG2-1341
Power Transformer: PT-5201 549-6045
Output Transformer: T-703 549-6050
Model: 112
Serial No. MA 0320
Power Transformer: PT-5201 549942
Output Transformer: T-703 549941
Model: 112
Serial No. MM9217
Power Transformer: PT-5201 549942
Output Transformer: T-703 549941
There are definite variations in the way the amps' model designations and serial numbers were noted on the tube charts. The transformers, power and output, for all 4 amps were made by the Midwest Coil & Transformer Company. Both non-tremelo amps have the same transfomer codes from late 1959 while both tremelo amps have identical tansformer codes from late 1960.
I've seen quite a few people reference the internet article that claims the amps were made by the Allen Organ Company. I never really thought that was true, however, I have no way to prove that. As time goes by I will try and collect and post more details on my other amps and possibly get some pics posted too.