Gary Mattis
Active Member
I got these 2 mono blocks with 3 others and I stripped them down and made 2 6L6 Class A mono blocks , one chassis has 7A96 stamped on the back and both are stamped made in us America , the s/n's are 2k apart but are the same otherwise. One has a corner of a sticker left (see pics) and says Minneapolis mn. Just wondering if anyone knows the brand ?. I'm guessing they had voice coil speakers originally ?, I put some vintage output transformers underneath inside of them. These surprised me by how good they sounded with 6X5,6L6 GB and 6AV6 tubes on a digital tuner, CD and tape deck. The sound with Sylvania blackplates and the RCA tubes is right up there with a Fisher 400 with Telefunken pre amp tubes ! . I had heard nothing but bad things about 6X5 GT rectifier tubes ? Why ? The 6X5 is rated at 70 ma and my 6L6 tubes use 23 and 25 ma each , well under spec at 50%. All of the transformers and chokes run cool after an hour - just warm to the touch. The 6X5 are original tubes ! , I read up and it seems like mostly only zenith equipment had problems with 6X5 tubes and no one else ! . It also looked like zeniths had poor design's to me that over stressing the tubes and the PTs. Maybe like the RCA hole in the plates 6AV5 GA tubes , it is an isolated problem that is brand specific ?. I think the dirt cheap 6X5 GT rectifier tubes are sonically fantastic sounding tubes !. I think these are console pulls and were FM also ! They have phono jacks. There was also a 12AT7 in the tuner section, 6V6 were the original output tubes.
