Optonica SM-7100 repair notes & mods

Performance report of this amplifier, as shown: ffseb.wordpres...
How to replace the output stages: ffseb.wordpres...
Throw money at me: / ffcossag
Music, when applicable, supplied by combatplayer.b...
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[@TheRailroad99]

Nice... Audio stuff is always interesting, so many different ways to design an audio amplifier...

[@domi7007]

Great Video quality!

[@FFcossag]

Thanks!

[@MrROTD]

I listen to the internet with a Yamaha RX-v490 integrated amplifier through my own custom speakers, it's quite nice.

[@electronic7979]

Nice repair video 👍

[@FFcossag]

Thanks 👍

[@tigerelectronics5966]

YAY! Finally a lot of new audio vids!! :D

[@FFcossag]

They do happen every now and again!

[@SuperBrainAK]

that is a very sleek amplifier, I just have a class-D car amp for my computer speakers

[@RTCLR123]

Nice Jbl' s! Do you find them " flat"?

[@dannyvanderheide6098]

If you still have this amplifier, would you please be able to measure the output voltage of the transformer? I have one in currently with a faulty mains transformer coil and can't find it anywhere on what the stock component should supply. If I know that I might be able to swap in a different transformer and get this old beast back to life again.

[@FFcossag]

It doesn't say in the service manual? I can't easily measure it, sorry.

[@dannyvanderheide6098]

@@FFcossag checked a 30 page service manual, 0 information on the output voltage of the transformer. They state the part number but with it being this old there is no documentation on it.

[@FFcossag]

Except that page 12 explicitly lists all the voltages, both DC and AC.

[@dannyvanderheide6098]

@@FFcossag shoot you're right, had totally overlooked that. well, my bad. True thanks for your help!

[@fouzaialaa7962]

i like audio stuff !!! i bought a cheap 50 $ class D amp on ebay and im thinking of adding Bluetooth connectivity to it !!so i bought a cheap bluetooth speaker for less than 10 $ but after i removed the shitty amp from the Bluetooth speaker and bodged it to the class D amp i got horrible noise !! like no sound at all its just a high pitched noise !!! the amp i removed from the bluetooth speaker was a lm 328 ..... i dont know if im stupid or something is wrong !!! are you open to trying this out ? less cables means less wires to fiddle with when you want to change the source !!

[@FFcossag]

Bluetooth speakers are awful and I don't touch them, lol.

[@Heimbasteln]

@@FFcossag Eh some sound good enough, especially if they have better BT protocols. Im still impressed that my Doss Soundbox XL goes down to 45hz at such a small size, even my Philips MFB 544 cant compete with it if you compare bass per liter.

[@armaansadiq536]

My Amplifier optonica sm 7100 STK ic problams

[@simontay4851]

Why does it have 2 phono inputs. Most people don't have 2 record players. I have a vintage audiotronic japanese amplifier that has 2 phono inputs. I modified one of them to be a line input by bypassing the phono preamp.

[@FFcossag]

It's "fancy", a status symbol. Why have one turntable when you can have two? ;)