Hi newbie here,looking for any help with Amp causing speakers to blown

Hi all,
Ok i just started getting into vinyl,i got myself a vintage tt pioneer pl-12r,along with pioneer seperates.

The amp is a pioneer sa-410,ok when i plug my speaker wires into the sockets at the bck of the amp,one speaker sounds as its blown,if i swap the cables to the opposite sockets the speakers fine.this is not constant starts ok but after say 5 mins it starts again.if i turn the volume up and down quickly it sometimes sorts it out,but again only for a few minutes,any ideas on what this could be,obviously its something in the amp im thinking.

 

Hard to troubleshoot over the web, but if you have a voltmeter, check the DC offset.

 

More than likely you have a dirty volume pot, but with an integrated amp that old it could be any number of things. Either have it serviced or buy something brand new.

 

Dc offset all good thanku.

 

I dont think it the volume pot,ive removed the top cover and noticed if i put a little pressure on the back plate either pushing it backwards or inwards it clears.
Can i assume it may be a bad connection with maybe where the jack plug sockets are connected to the mother board

 

The jacks would be where I would start troubleshooting, yes. First thing make sure they're nice and clean. Same for your interconnects/cables--don't know if they're 'vintage' too? If so you might try a different pair.

Also, I'm assuming you're using the phono input for your tt. Or do you have a separate pre? Either way have you tried listening through the other inputs and/or with different sources? That may help isolate the issue.

 

Thanks for your input,i am playing through phono input,tried other inputs and sound is really quite,im not using a pre amp,although am looking to purchase one.as for the phono jacks when i bend them slightly amp side it corrects itself,but it does also when i put a little pressure pushing where the inputs sockets connect to the m- board.

So seemes to be something to do with that side of things.
I have disconnected the amp and gave it a good clean using wd-40 cleaning spray for m-boards.this did nothing,so when i put the cover back on the amp i applied a little pressure on the back face bending it slightly outwards and put screws bck in place,for now this seems to be solving the problem...i think it maybe where the phono jack sockets connect to the m-board...so may be best to get it checked out.

Also seeing im here,the amp has 4 ports for 4 speakers the top ones for left and right work fine,but norhing putting speakers in bottom to,any ideas why this maybe,ty

 

Glad it's working for the moment, but I'm with you in that you ought to get it checked out by an expert. I'd be concerned about using it as is if it was sending loud sounds or pops through the speakers. Both for your speakers and for your heart.

Not sure I understand your question about the speaker connections.

 


Yep indeed think i take it to a techie..

Speakers...ok... On the back of the amp i have sockets for 4 speakers,its the ones with the red and black switch type...so you lift the switch put your speaker cables into the hole(lol) and release to hold cable tight.ok i have enough inlets to plug in 4 speakers.left and right speakers on the top row,and left and right on the bottom row...top row plays sound through speakers,but if i put cables for another set of speakers on the bottom ones i get no sound, hope you can understand how i put that

 

Ah ok that makes sense. Does your amp/receiver have a speaker selector? Some models have an either/or switch, so that you only run one pair at a time. Some have separate toggles for each pair, so that pair A can be turned off independently of pair B. So, check that first and make sure the B pair is engaged. The next thing I would check is that the impedances of the speakers matches the rated output for the amp.

 

Ok lol i have got to push buttons on front of amp above which says speakers.
Under one switch says on of with symbol for button either pushed in or out,the other says a/b with same symbols,is this the ones your talking about

 

Just pushed one and yes cuts sound to speakers,pennies just dropped to do this when headphones in as inserting headphones dosent cut sound to speakers like on newer systems,so what if i still get no sound to second pair if buttons left on,or can i not have all four speakers going at one time.

 

If you have a soldering iron you could do a quick touch where the connectors meet the board. I think the bottom plate comes off fairly easy for a look.

Looks like you can only have one set of speakers playing at one time. You can press the button for speaker on/off to disable speakers when listening to headphones.

 

Should state though, if you aren't comfortable with the soldering iron, you should take the unit to a tech. The problem with a tech looking at it is they may charge more than the amp is worth.

For 40+ year old gear, it's good if you have some di-it-yourself skills.

 

Lol yeh im pretty handy,ok with soldering,thanks very much for your time,been a great help...you anygood with drivers,got a set of vintage bang and olusfen beovox 3800... Want to replace midrange and tweeters,but dont know what ones would be compatible

 

My son blew the woofers on a set of Paradigm tower speakers I had a few years ago. I just bought a set of woofers that looked like a good match from Partsexpress. I can't say they sounded as good as new but he still uses the speakers today.

 

Ok thanx,i will take a look and see what they have,,,