Project/One Mark III - Issue with speakers not wanting to come in at power up.

[RJB-Stereo]

Hello,

I’m having an issue with my receiver. The same thing happens whether I’m using Speaker set A or B.

Note: This unit is virtually identical to the Pioneer SX750 and I have been using the 750 service manual to repair the unit with great success.

- Volume set to 0.
- Power receiver on.
- Wait for relay click.
- Begin turning the volume up with no sound.
- After 3 to 4 seconds I can turn the volume to roughly three and I get the left speaker.
- After another 5 to 6 seconds I can turn the volume to roughly 6 and the right speaker comes in. It comes in hard sudden at that volume and I’m not happy with the jolt to the speaker.
- If I don’t touch the volume, the speakers never kick in.
- After that, I can volume up or down with no issues, even going back to 0 and leaving it for a while, both speakers respond perfectly and sound great and seem to be evenly balanced as the volume is increased.
- If I power the unit off and back on, I have the same issue even if the unit is warmed up and was playing fine moments before.

I tried multiple times using Deoxit D5 liberally on the volume dial and working it vigorously but it has not helped.

Do you think the switch need replacing? Or, is there something else I can try?

Thank you in advance for any advice.

Regards,
Bob

 

[audiotemp]

Check also other controls.. balance, tone, switches not just volume. Also relay may cause this in same way.

 

[w3jn]

Moved to Solid State Forum.

 

[RJB-Stereo]

Check also other controls.. balance, tone, switches not just volume. Also relay may cause this in same way.

Thank you,
I have Deoxed every switch and dial with no change to the speakers. They all seem to be working well.

I will take a look at the relay. I hadn’t thought of that.

Thank you,
Bob

Moved to Solid State Forum.

Thank you for forwarding my post to the appropriate forum. I am new here and still learning the ropes.
The help is much appreciated.

Regards,
Bob

 

[w3jn]

No problem. There are a ton of forums here and it’s not all that easy for a new member to navigate all of them.

And welcome to AK!

 

[dimanag]

Hi bob,
From your discription it is the relay. Very dirty contacts. Clean it or put a new one in!

 

[RJB-Stereo]

Hi bob,
From your discription it is the relay. Very dirty contacts. Clean it or put a new one in!

Thank you,
I found a similar replacement for the relay online last night and placed it in my cart just in case.

My plan is to clean the existing one thoroughly then test it.

If cleaning doesn’t help, my backup plan will be to purchase the replacement and swap it.

I’ll update this thread with the results either way whether or not I get it fixed to hopefully help others with this issue.

Regards,
Bob

 

[RJB-Stereo]

Well, the two people who commented to check the relay were spot on.

I powered on the receiver and tapped the relay with the handle of a screwdriver, both speakers immediately came on at low volume and responded to the volume control.

I’m going to attempt the clean it and see if I can get it working, if not, I can get a replacement shipped to me for under $15.00.

Thank you both for your advice. I will update this post with my results either way.

Regards,
Bob

 

[RJB-Stereo]

I popped the cover off the relay, removed the spring to allow me to remove the contact bars.

I shot a little Deoxit onto the contact points on the bars and the contact points on the relay base.

Using a Q-Tip, I lightly rubbed in the Deoxit on all the contact points and could see some darkness on the Q-Tip.

I replaced the cotact bars and the spring, popped the cap back on and tested.

As soon as the relay kicked in, both speakers were there and playing perfectly.

Thank you for your help identifying and correcting my issue. This receiver sounds better with every fix I make.

Regards,
Bob