Pioneer SA-9900 Quiet on 1 side ( balance )

[BomberHarris]

Nope, Its a one knob only .. I've had those sony dials also.. theyre both nice and a pain at times! haha

[agk]

ok guys, i've figured out how to replace the lights and which ones I need.. now just about the sound down on 1 side.. any ideas?

The first thought in my mind on reading the title of this thread was "are there two fuses inside (one per channel) and is one blown?".
Not been inside one of these but that used to be a common thing on some older gear.

...

[agk]

It does have a pair of fuses. I would have to add though that if one is blown it blew for a reason. The best thing would be to get the amp reconditioned by a reputable company as there are likely to be all manner of problems in a piece of this age.

Good luck with it man, truly a beauty.

[nat8808]

Hi, Yes - I've switched the speaker cables around both ways, but still the right side always goes quiet.. I've also tried connecting it to phono and aux , but the sound is still down on 1 side..

Didn't you say you switched the speaker cables around and it is still quiet on the righthand side each time?

That can only be your speakers or speaker cables... (else the problem would switch sides dependent on which speaker was attached to the dodgy channel).

[nat8808]

If that's not the case, see what happens when you plug in headphones. If it happens on the headphones then it's not the power amp stage, it's to do with something before it (controls or inputs or pre-amp section).

Could the attenuation switch be dirty and so still connecting on one side of the switch (and therefore attenuating one side). That would be an easy fix and a something to expect for an old amp.. Shame about the bent switch I see in the video. Turn it off and get some switch cleaner squirted in the attenuation switch (best from the inside probably) and switch it about quite a lot...

Actually, what happens when you move the attenuation switch to different positions? Forgot it has different levels of attentuation.

A very nice amp! Pretty rare - hope you didn't spend too much as I bet they could end up at quite a high price. I had the SA9500 which is a slightly less powerful version and without the light behind the volume control. Essentially the SA9900 is the SA9500 MkII but because they upped the power they called it the SA9900..

[nat8808]

It does have a pair of fuses. I would have to add though that if one is blown it blew for a reason. The best thing would be to get the amp reconditioned by a reputable company as there are likely to be all manner of problems in a piece of this age.

Good luck with it man, truly a beauty.

Age of the fuse can be a good enough reason..

I bought an amp on the basis that the distortion described could be a blown fuse on half a supply. I was right! Replaced the fuse and it's worked fine for the last 3 years and one of the best amps Ive had. Didn't seem to be any reason for it to blow other than age and the strains of powering up and down, heating up and down all the time (I leave it on).

[nat8808]

And then, another thought.. if I remember correctly, the pre-amp and power amp are seperate and are connected down the side externally by two small bars.

Check that they are connected ok. Then, if you have a jack to phono cable you can take out those bars (obviously do this while the amp is off) and connect an ipod with volume down to the power amp section. turn it on, turn up the volume on the ipod and see if the problem is still there (the controls on the front won't work cos they're part of the pre-amp section which you've bypassed now.).

If you've got another amp to hand and a phono to phono cable, you can plug the preamp output to the other amp with your source playing into the Pioneer (but speakers into the other amp) and see what happens. Probably the same though as trying out the headphone socket..


Edit: They're not connected by bars.. there's a simple switch! Switch it to "seperated" (might have to unscrew and remove the plastic tab if it's there, which stops the switch moving).

Aaaaa, memories.. ignoring my first non-allinone hifi purchase, a Pioneer 610 which WAS my first ebay amp purchase, the SA9500 was my first ebay amp purchase!