Pioneer A400 Help

[admin_exported]

Hi, I'm having a bit of trouble with my Pioneer A400 amp. I got it a while ago. I only get decent sound from one side. I can hear some low music from the other but it's not loud at all. I've swapped the speakers around and it does the same. The music is coming from Line in.

I don't know much about hi fi's but I would be grateful for any help. I'm not looking for an amazing setup. It's set up with 2 B&W DM110. I feel like an idiot writing here about this because I haven't got much clue if they go or if I'm doing something wrong.

Thanks

 

[Anonymous]

Give it a tap on the side, top, front, back (with the force you would of knocking at someone's door). If this fails, lift the amplifier up give it a bit of a rock in your hands and if this fails, open it up and clean it out. REMEMBER TO LEAVE THE AMP OFF THE MAINS FOR AN HOUR BEFORE WORKING INSIDE DUE TO THE HORRIFIC AMPAGE WHICH CAN BUILD INSIDE CAPACITORS.

 

[drummerman]

[quote user="Hughes123"]REMEMBER TO LEAVE THE AMP OFF THE MAINS FOR AN HOUR BEFORE WORKING INSIDE DUE TO THE HORRIFIC AMPAGE WHICH CAN BUILD INSIDE CAPACITORS[/quote]

Remember the 9'oclock watershed. Sounds like an 18 cert. Got me scared.

 

[Anonymous]

[quote user="drummerman"]
[quote user="Hughes123"]REMEMBER TO LEAVE THE AMP OFF THE MAINS FOR AN HOUR BEFORE WORKING INSIDE DUE TO THE HORRIFIC AMPAGE WHICH CAN BUILD INSIDE CAPACITORS[/quote]

Remember the 9'oclock watershed. Sounds like an 18 cert. Got me scared.
[/quote]

I don't want to be held responsible when someone gets the insides of oil in paper through their arm...

 

[a91gti]

Whip the lid off, inside you will probably find a pair of fuses right next to each other, swap them over. If that sorts it replace them.

 

[Anonymous]

[quote user="taxiboy"]Whip the lid off, inside you will probably find a pair of fuses right next to each other, swap them over. If that sorts it replace them.[/quote]

It's certainly not the fuses if he's getting that level of volume out of it. I would say there was just a dry joint somewhere.

 

[a91gti]

...and what level of volume is that?

 

[Anonymous]

Louder than just pre-amp volumes I am presuming...then again, presumption is the mother of c*ck-up as my History teacher tells me.

 

[a91gti]

Exactamundo duder! That said, you at least remembered to tell him to turn it off, which I forgot!!

 

[Anonymous]

ok play nicely boys...
to the OP - Does this problem only occur through the Line-in inputs? if so then the easiest and cheapest solution is to just use a different set of inputs - a quick glance at the back of my A400 shows 7 sets - should be more than enough.
I would be very hesitant about following Hughes advice as, if you have one dry solder joint, knocking the amp in this respect may just loosen another solder joint (no disrespect Hughes).
Also, try the same source through a different Input to make sure the source and/or interconnect are not responsible for the problem...

 

[Anonymous]

[quote user="taxiboy"]Exactamundo duder! That said, you at least remembered to tell him to turn it off, which I forgot!![/quote]

I've had the same problem with my JVC so I know what I'm on about - I could also expand by saying that it wise to check the silicon filler between the transistors and the heat sink. If my memory serves me correctly, I believe the A-400 had MOS-FETs so they can get a little toasty sometimes.

 

[Anonymous]

hi, thanks for the help. I've tried giving it a knock but it hasn't worked.

The only way I can describe the volume from the working side is loud, well normal. I've tried a lot of different music but when I listen to adam and joe I can hear one person talking fine but the other sounds like he's standing far away from the mic.

I've switched the amp off now and I'll wait an hour. I'm not looking forward to taking the top off!

 

[Anonymous]

[quote user="ifitsoundsgoodlistentoit"]
I would be very hesitant about following Hughes advice as, if you have one dry solder joint, knocking the amp in this respect may just loosen another solder joint (no disrespect Hughes). [/quote]

No you are entirely correct about being cautious about doing this - the only thing is, giving it a little move in the air will allow the joint to reconnect if possible without causing vibrations which would disconnect others - and dry joints only happen over quite a long period of time so the chances of two happening at the same time are very slim. But ofcourse, I was playing with a £40 amp, not a £100 like the A-400!

 

[Anonymous]

[quote user="Jonestime"]I'm not looking forward to taking the top off! [/quote]

Then don't! You'll only worry yourself more and besides you may be able to find the solution from the outside. IFITSOUNDSGOOD has a good point about the line inputs being the problem.

The best question I can ask you, is how loud would you have to turn the amp up with just the broken channel to get it to be the same as 10 o'clock? If it's not alot (like 12 o'clock) then the power amp is still working...if it's about 4 o'clock then the signal path isn't reaching the poweramp stage or the amp itself isn't working correctly.

 

[a91gti]

Ifitsoundsgoodlistentoit can you refrain from making it seem that there is an argument going on when there is NOT! The whathifi bods have itchy trigger fingers at the best of times. I merely said that Hughes123 had thought to tell the op to turn the amp off before opening where I had not.

 

[Anonymous]

Fixed!!!!

This might sound strange.

It was the volume knob. When it was turned right down there was still some music coming out from one speaker. I pulled the plastic off the volume. The metal that sticks out is made out of two separate parts. The front part had slipped out of line with the other. All I had to do was hold on to one and turn the other.

It was simple in the end. Thanks for all the help because with out everyone that posted I wouldn't of gone round to checking it out. I was thinking of giving it away. Now I can listen to adam and joe - that's not all I listen to, just in case anyone was thinking I was wasting it and talking.

 

[Anonymous]

[quote user="Jonestime"]
Fixed!!!!

This might sound strange.

It was the volume knob. When it was turned right down there was still some music coming out from one speaker. I pulled the plastic off the volume. The metal that sticks out is made out of two separate parts. The front part had slipped out of line with the other. All I had to do was hold on to one and turn the other.

It was simple in the end. Thanks for all the help because with out everyone that posted I wouldn't of gone round to checking it out. I was thinking of giving it away. Now I can listen to adam and joe - that's not all I listen to, just in case anyone was thinking I was wasting it and talking.

[/quote]

lol, i was going to suggest you check the volume controls but as you said it was only the Line In Input that was creating the problem i dismissed this myself... anyway great news that you have "fixed" your amp. i hope you have many more enjoyable hours from the amp!

 

[Anonymous]

[quote user="taxiboy"]Ifitsoundsgoodlistentoit can you refrain from making it seem that there is an argument going on when there is NOT! The whathifi bods have itchy trigger fingers at the best of times. I merely said that Hughes123 had thought to tell the op to turn the amp off before opening where I had not.[/quote]

actually i posted the "play nicely" comment in response to your "....and what volume is that" comment - which did seem rather sarcastic. i didnt post in time though and you had made another reply before my post appeared. i wasnt trying to get anyone in trouble, just a harmless comment to calm any argy-bargy that seemed to be going on at the time. apologies if i misinterpreted your comment

 

[a91gti]

No probs iisglti, I do have a sarcastic lilt.

 

[professorhat]

With a totally tropical taste?

 

[Anonymous]

[quote user="professorhat"]With a totally tropical taste?[/quote]

no i think its more like... a totally tropical taste ;-)