Just a quick update..... been looking for a week now and still nothing on Ebay UK....plenty in the states but with postage and taxes your talking over £100 each  :grr (amp is only worth around £100).On the bright side,you can get 4 pair of boots on it  :dbtu: sooooo.......

How dare you call my speakers C..... !  hahaha ok yea they probably are,but honestly they sound pretty good, or maybe I'm just such a wonderful guitarist I can make any crap sound good ? ok maybe not !

Thank you for the advice, as you probably guessed I'm no genius with guitar amps  I know basic electronics, enough to keep things alive (usually), anyhow.... now I know where I'm going with it  :dbtu:
I did look on Ebay a few times but nothing turned up, maybe 60watt 8ohm speakers arent that common, also, I'm in the UK which probably makes a difference, no chance of buying one from the USA, the crazy UK import taxes cost more than the items now !
I'll start hunting again but still not quite sure what to look for,if I go with 2 8ohm speakers what sort of wattage would be ok ?

I searched Google for a schematic but cant find this model, I did find one similar that might help though

Thanks again  much appreciated

Hi everyone  :tu: my first day and first post !   a while back I was given a Yamaha hundred B212 from the early 80's I think, it was working but the volume was very low.I finally got round to taking a look today, first thing I noticed was the speakers, the originals were had been replaced (2x 60watt 8ohm yams) instead it had 2x 400watt 4ohm subwoofers !!!! (the amp is rated at 4ohm) now even my dumb brain knows that aint good lol, no way to match the impedance !  so I hunted round and found 2 tweeters rated 100watt 4 ohms, so hooking them to the subs in series/parallel would give me 4ohms 
Checked polarity etc made sure all 4 were working and gave it a go.
it sounded really good ! just about perfect as I play mostly acoustic,I was sitting playing and feeling smug then tried to crank it up a bit..... same as before  very low volume. Seems about half of what it should be (its a 100watt amp btw)
Only other thing I can find is one channel is off and buzzes like mad. the other channel works great, nice and clear on both high and low inputs but I'm guessing this has nothing to do with the problem (I do a lot of guessing lol)
Any ideas guys ?