converting a guitar amp to a Hifi amp...

IMO...

It's a hell of a lot easier and probably cheaper to just go down to your nearest secondhand store and buy a small 1980s hi-fi amp - something like a a Sanyo, Pioneer, Panasonic, Sony or whatever in the 25w/channel range. They go for £25-£50, and it will be a proper stereo amp with a preamp designed for normal hi-fi level signals. Most of them sound quite good too.

What you've got is a mono amp of unknown (but if I remember, unremarkable) tonal quality which will need a fair amount of work to make it useful. I wouldn't bother. If it works, keep it as a spare amp - you never know when it might come in handy - but I wouldn't spend any more time and effort on it than the parts inside are worth... which is next to nothing.

I used to come across these fairly regularly in junk shops ten years or more ago, and no-one wanted them even then.

 

The 70-80's Sansui, Kenwood, etc... stereo amps were in a distortion spec race and were adding massive amounts of negative feedback which resulted in really strident sounding gear. This amp would probably sound a lot warmer, but probably blurryer and less resolution.

Our beloved guitar amps are decended from cinema amps, so there's precedent for using an early generation transistor guitar amp to listen to music through. Back to the days of glorious mono, just like some Japanese tube junkies. The tone circuits are probably similar to cheap stereo design, and compared to a modern set up, you probably have a "fully discrete" circuit. Just think of how you can wow your buddies with this old school set up. Hey, I almost dumped my Levinson/Classe set up for a single ended EL84 Audio Note a few years back. It just played music really well. Might need to pad down the input a bit, but have fun. The worst you could do is blow up the probably unprotected output transistors and then you'd be back to the paperweight you had before.

 

You're only going to get mono output, although most stereo recordings are set up so this works ok. I have to agree with another poster, decent stereo amps are not super expensive at pawn shops-$100 will get you something that's pretty respectable. And $250 will buy you an all tube, decently maintained Scott or Fisher stereo amp from the 60s. They really do sound great, far better than just about any SS design.

 

There you go. And those weren't too heavy on the NFB. Should sound pretty nice. A little contact cleaner and you'll be rockin the house. Careful about getting contact lubricant. And getting it on the string that runs around the tuner dial. That tuner is a variable capacitor and just needs to be clean between the plates. Tuner cleaner/lubricant is for older TV sets that had multiple contacts for the different channels.

 

Yes, those are quite nice. I've still got a little Pioneer 30wpc amp (from a few years after that I think) as the power amp for my computer sound/home studio setup. Sounds good.

That Fal Kestrel... I'm almost surprised there are any left, and not at all that it was found in a skip! I can remember having a look inside a dead one (which was also quite normal) once and thinking that it was a pile of junk. I haven't seen one for a few years though. The funny thing is that I think I might even have played a gig about 15 years ago where the PA was the 100W 4-channel version - it was something like that anyway - it had no volume at all. My '58 Fender Princeton (all 4 watts of it) was loud enough to keep up with it, unmiked outdoors . Luckily the entire audience was about ten people .

They were kind of like Torque amps are today - they look like they should be OK from the outside, but actually they're just too cheaply built to really be any good.

 

I'm not certain about that model, but it can't be any more than 30W per side if the consumption is 130W.

Yes, it can use any speakers between 6 and 16 ohms. You will lose a little power with higher impedances - but don't worry about it, almost all hi-fi speakers are 8-ohm anyway. The difference between 6 and 8 will be negligible.


Is the switch on the Kestrel one of those square rocker switches BTW? I think the later ones had those... if so, you need to push in the grips on the inside, then push the switch out through the front - it's a bit tricky.

 

Well,

There you guys go....

...and here I was thinking of just getting
a standard guitar cable and plugging one end into the phones jack of the CD player and the other end into the guitar jack of the amp.

Then dial it in until it sounds good.

Yeah I know, but it is all relative folks.

It ain't no high fallootin' audio-phoole,
cork-sniffin' stereo;

BUT

it works and you can listen to some
discs or play along with them (depending on the amp).

 

Matter of fact, it ain't no "stereo" at all....which channel do you prefer to listen to, left or right?

 

This isn't always a good idea. If you put a mono plug into a stereo socket, you'll short the right channel (ring) to ground. Sometimes the headphone driver IC does not like this. Usually they're short protected, but not always...

You're better with a stereo cable split into two mono jacks at the other end - you can plug them both into the amp at the same time. You'll now be able to hear both halves of the stereo - mixed into mono - and you won't risk frying the driver IC.

Sorry to be boring...

 

Unlikely, without a lot of experience and a schematic. Solid-state is nowhere near as easy to troubleshoot as tube - stages are often DC-coupled, which means faults on one can show up on another... and you may find some of the transistors are obsolete and hard to get. And if it's some non-standard IC that's died, forget it!

If you were offered the refund, take it! It's a little cheeky of the seller not to refund the postage though. If he sent you a dead amp, why should you be out of pocket for that?

You're right that it isn't worth spending £50 to fix it.

BTW, I did have a quick check in my loft to make sure I hadn't got anything like this still lying around that you could have... but no.

 

I strongly recommend looking for a Fischer or Scott stereo tube head from the early 60s. Great sounding, pretty foolproof. Get one guaranteed to be working, or better yet, recently serviced and you shouldn't have to pay more than $300 or so.