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Amp from an old transformer.

My old home stereo was broken and I got a new one as a gift. I want to use the old speakers and transformer as an amp for my home office Is this at all feasible? If possible could you point me in the right direction?

gmoon6 years ago
How old is the amp? Most solid state amps don't use/need an output transformer (some, especially really old SS amps have them), but tube amps do. Generally, amps need a power transformer, and only some have output transformers...although some old (unsafe) tube amps regulate the mains voltage directly and don't have a PT at all. Stay away from those without modification.

One sure way to tell--if it's stereo output that uses output transformers, then there must be two output transformers (along with the the PT)...

So only one transformer indicates it's probably a power transformer. Yes, you can reuse a PT, if it's functional. It's likely "low voltage," something in the 18-48V range. Fine for all sorts of projects, including a DIY SS amp.

Yeah, the speakers are perfectly useable, with the right amp (output impedance).
The transformer might not be of use but there are loads of DIY amp projects online - finding one that matches the speakers and adapting it to the parts you have might be an idea...
Goodhart6 years ago
Yes, as Grenadier implies, you would have to also scavenge the circuit containing the actual amp. It will commonly contain an IC that looks like this....
grenadier6 years ago
The transformer is for impedance matching, it amplifies nothing.