Classic Hifi Care

I have had this little mono amp forever. It was my stepdad's and I got it when he passed in 1987. He used it as a bench amp. There is nothing special about it, outside of the fact that it is populated with high-end tubes that are worth far more than it is. It has a PACO-branded Mullard sourced 6CA4 rectifier, one Mullard 12AX7 and one Magnavox-branded, RCA-sourced 12AX7, then a push-pull pair of Mullard EL84, 6BQ5 audio output tubes. It pulls 38 watts in full flight, has a factory fuse in the primary circuit of the power transformer. I recapped the chassis with the exception of the filter caps. I'll leave them like they are for the time being. I'll get some pictures and get them posted.

I've got one of those. Pretty sure I built it from a kit. I built a Heathkit mono AM-FM tuner to go with it, both of them in service at my Dad's office for background music. It was replace eventually by a Technics low-end solid-state receiver after staff reported a burning smell. Likely the filter caps shorted. I figured that the power xfrmr was dead so it was relegated to the someday shelf. Since then I've wondered if maybe they got it turned off n time and the iron is still OK.

Chris Campbell

There is only one way to find out, Chris.

Bill

I have no idea where Sam got this amp. He may have kit-built it. The iron on it is miniscule in comparison to bigger amps. I don't know if the fuse is in all of them or if Sam put the fuse in later. I doubt it, though. That would have cost money. Sam was the second tightest person I ever knew. I can see where it wouldn't take much to take out a PT without some protection. Somebody before me scratched the tube types with an awl and put a 6X4 for the rectifier. The socket is nine-pin, a 6X4 is seven pin.

I dug this little amp out this afternoon and used it to play 45's. The speaker I used was an 8" parts speaker, just connected with test leads, laying on the bench. I need to rig up a good mono speaker setup. I fed my little RCA 45 player into the phono input. It sounded horrible, tinny, distorted. I connected the changer to the tape input. There it sounded great. The phono input must be for a low-level magnetic mono cartridge, such as the GE VR series. The ceramic cartridge in the RCA player overloaded the amp. I played 45's for a couple of hours. The little amp pulls 38 watts. I believe it would sound really nice with a good speaker. I took pictures that I will get loaded and on here for you guys.

My best memory of good mono sound was from Lucky's Record Shop when I was a kid, a place where they would give you a listen to records. At the counter they had a manual turntable with a long arm behind Plexiglas to keep customer fingers away, and a big speaker of some sort facing out under the counter. I have no idea what the amp was. But when they cued up the record, there was a satisfying thump when the stylus caught the lead-in groove, and what I recall as uncolored, accurate sound in the very large room.

Try a nice coaxial speaker in as big an 'infinite baffle" (not sealed up) box as your shop allows.

Chris Campbell