want to know what this is

[marcushifi]

I have this tube amp? but there is no power switch and I just want to know what exactly it is so I can see if Id have a use for it. To me it looks like an amp with right and left inputs in front and speaker inputs in the back. But im new to tube amps/tube anything. Just want more information on it if people can help.

Thanks!

 

[RWood]

Very nice. Appears to be a 6BQ5 push-pull power amp with Olson Output transformers. Good for about 15 watts a side.
Power cord appears to go through a fuse and straight to the power transformer, so it might have been switch on and off from a preamp, which is what you would use ahead of this to select inputs, adjust volume and tone etc.
Make sure you connect speakers to it before plugging it in. Seems to have been very well made.

 

[BinaryMike]

It's an old homebrew project and is probably based on a published design, likely from a magazine. Someone might recall it if you post the tube complement. Power output will be around 15W per channel and performance is likely to be excellent. Assembly quality is a bit lacking, e.g. heater wiring isn't properly twisted. Considering that essentially ALL parts under the chassis are likely to need replacement at this point, my approach would be to rip it all out, including the tube sockets, and rebuild completely, which would be easier with a schematic in hand. I would check the transformers very carefully before proceeding.

 

[marcushifi]

Very nice. Appears to be a 6BQ5 push-pull power amp with Olson Output transformers. Good for about 15 watts a side.
Power cord appears to go through a fuse and straight to the power transformer, so it might have been switch on and off from a preamp, which is what you would use ahead of this to select inputs, adjust volume and tone etc.
Make sure you connect speakers to it before plugging it in. Seems to have been very well made.

Awesome thanks for the info!

 

[marcushifi]

It's an old homebrew project and is probably based on a published design, likely from a magazine. Someone might recall it if you post the tube complement. Power output will be around 15W per channel and performance is likely to be excellent. Assembly quality is a bit lacking, e.g. heater wiring isn't properly twisted. Considering that essentially ALL parts under the chassis are likely to need replacement at this point, my approach would be to rip it all out, including the tube sockets, and rebuild completely, which would be easier with a schematic in hand. I would check the transformers very carefully before proceeding.

Thanks for the info.

 

[mhardy6647]

Looks like better than average (e.g., better than my) DIY with what looks like very nice Japanese-made output iron.

 

[radioactive]

Looks like better than average (e.g., better than my) DIY with what looks like very nice Japanese-made output iron.

I'm on your side on this one
I really dont see anything that might need replacing underneath those olson oil filled caps look like they might still be better quality caps than some diy amps used back in the day which leads me to believe that mabe the person bought this a a kit through olson.

 

[gadget73]

The can cap and the blue cardboard ones might be a problem. No idea if the Olson oil caps are better than other Japanese ones of the period. Hopefully so, the usual grey Japan ones were pretty lousy.

Certainly looks well done.

 

[cademan]

there is no power switch and I just want to know what exactly it is so I can see if Id have a use for it.

It is a straight power amplifier. Think of it like a custom car stereo amplifier like the one's people put in their trunks. Being a straight power amplifier, as mentioned, it would most likely turn on once you plug it in to the wall. A separate preamp would be needed for tone, volume, and two or more inputs.

Use some pretty efficient speakers in cabinets and that thing could shake the walls.

 

[trainbuftony]

I have been seeing a lot of these potted Japanese transformers popping up here lately. Olsen, and REX specifically. I have asked a few friends what they know about them and there isn't a whole lot of info on them. Someone somewhere said that all of the Japanese potted transformers came from Tamradio. I do not know how accurate that statement is but I would sure like it to be true. Tamradio makes Tamura Tango and a few other really high end names. I recently stumbled into 4 of the REX ultralinear transformers at a price too low to pass up. I have not even started to build an amplifier around them, but I have high hopes.

 

[RWood]

Good info. I wondered if that was the "T" in T-275. Did a search and a reference to Tamura popped right up. Take a look at
eBay item number: 262131147438

 

[primosounds]

I have been seeing a lot of these potted Japanese transformers popping up here lately. Olsen, and REX specifically. I have asked a few friends what they know about them and there isn't a whole lot of info on them. Someone somewhere said that all of the Japanese potted transformers came from Tamradio. I do not know how accurate that statement is but I would sure like it to be true. Tamradio makes Tamura Tango and a few other really high end names. I recently stumbled into 4 of the REX ultralinear transformers at a price too low to pass up. I have not even started to build an amplifier around them, but I have high hopes.

While, the T on the transformer number would lead you to believe that it is a "Tamura" output transformer, it may not be. I don't know enough about Japanese transformer manufacturers from back in the 1960s and 70s to be sure. But, I know there were many transformer manufacturers in Japan back then when the Japanese electronic industry was already becoming a market force. So, it maybe Tamura, Tanaka, Toyo, Tane, ???