Connecting a microphone to hifi amp

[Tim Hall]

My Scout hut has a Technics amp from Thee Olden Days.
This has phono, aux, tuner, tape inputs using RCA type sockets.

Someone has procured Amazon's finest 600ohm karaoke microphones, fitted with quarter inch jack plugs.

There is also a multitude of adaptors, leads and gubbins to allow plugging in of a microphone into any of the RCA sockets.
Of course it Doesn't Work.
A brief bit of searching suggests it's because the signal level from the mic is too low and a pre amp of some kind is required.

The aim is to provide some kind of P A for an upcoming meeting.

What sort of thing do I need? Is it even possible?

[rogerzilla]

Not evrn the phono input?

[Tim Hall]

Tried the phono. The wrong sort of buzzing noises were different to those heard when using the other inputs but that's all.

It's possible that the multitude of adaptors and gubbins are fubar though.

[road-runner]

Tim, I suggest you consider a mini mixer such as this one as it has a mic input (it is a combi socket which will take the 1/4” jack plug) and a normal stereo cable with RCA plugs at both ends will connect it to your son’s amplifier, where going into either the aux, tuner or tape inputs will work fine. Naturally, the mixer has the right preamp.

[Feanor]

Yes, what RR said.

Microphones are not the same as either Phono or Line Level inputs. They need an input designed for them.

To make matters even worse, some mics require power to be sent up the line to them, called Phantom Power.
The mixing desk or pre-amp needs to supply this.
Hopefully, they don't need this and you can forget I ever said this.

The item RR pointed to will do what you need (including the Phantom Power if needed!)

[road-runner]

The aim is to provide some kind of P A for an upcoming meeting.

I didn't ask the obvious question: How many people are you expecting?

Using a hi-fi system with its speakers may suffice for a dozen people but probably not for large meetings, both from volume and clarity perspectives. It can depend on how powerful the hi-fi system is and how many tone controls it has (hint: turn the bass down to taste and leave mids and highs at their centre positions).

Do you know any musicians? If you could borrow a PA stage monitor and a Shure SM58 mic you will in a better position than a home hi-fi. If not, do what you can with what you have.

[chrisbainbridge]

We have a local company who rent out complete kits for events, all colour coded and guaranteed. May be worth doing a google maps search.

[Tim Hall]

The aim is to provide some kind of P A for an upcoming meeting.

I didn't ask the obvious question: How many people are you expecting?

Using a hi-fi system with its speakers may suffice for a dozen people but probably not for large meetings, both from volume and clarity perspectives. It can depend on how powerful the hi-fi system is and how many tone controls it has (hint: turn the bass down to taste and leave mids and highs at their centre positions).

Do you know any musicians? If you could borrow a PA stage monitor and a Shure SM58 mic you will in a better position than a home hi-fi. If not, do what you can with what you have.

Oops, kept meaning to reply but went out for a bike ride instead.

Say 35 people maximum, room is at a guess 10m x 4m. It's a fairly, but not terribly, echoey space.  The hifi runs four speakers, two at the front of the room, two at the rear. 
We could, I'm sure, borrow some kit from somewhere if it comes to it. 

I'll have a look at the minimixer you suggested, it'll come in handy for other stuff we use the room for.

In fact, if I go down the borrowing kit route, I'll see if I can get away with borrowing a suitable mixer as a trial and if that works, shell out for one.
 

[road-runner]

That sounds like a reasonable plan. I hope it goes well for everyone.