Sansui 7070 no sound

I have been trying different setting , i really dont think its the Cornwalls now . Its hard to describe . But its deffinately there (the pop) that is . Other than that its sounds wonderful?
 
As far as before and after

Its easiest i put it like this

Pops at 9oclock with tones adjusted bass 3 oclock and loudness on, before and after test.

Pops at just past 9 1/2 almost 10 oclock bass flat and no loudness, before and after test.

To me nothing has changed with test as far as when the pop happens. I do use the same track each and every time.

Maybe we are chasing a ghost lol, no really could it just be the cornwalls causing this? The sound gets extremly loud at the setting i mention almost 10 oclock on the cornwalls . But the garage speakers will let you get just past noon. ?
They do work fine on my other equipent .

Since you were able to push the volume level higher with the garage speakers I would find another set of speakers and try that. Without more advanced test gear it's hard to determine how well the amp is truly performing.

Joe
 
The only other thing i know to try with what i have will be the Pioneer CS 99As They are 8 0hm and candle handle alot more power than the garage speakers, not near as efficient as the Cornwalls though.
After that im out of ideas if any advanced test gear needed.
 
I just tried a pair of Klipsch Kg4s which a very nice speakers (same results). I would like to say this as far as that pop goes , not trying to change from what i origianly said .

The pop as we decided to call it , well the more i listen to it its like a (spike or snap) and it seems to come through the horns (highs) from all speakers tested. Not sure if this changes things but i have been trying to explain the best i know how . You really cant determine if its going to the woofers unless i start disconnecting speakers (highs) .
 
Ok tried with the Pioneers, they dont seem to pop at all . They will get to there limit and start distorting . There limit as i would call it is around 10 oclock on the volume and only pegging just above the 1 watt mark on the VU meter . It was loud and sounded good up until they started distorting. So i didnt want to push them any further but no pops?

It doesnt make since to me .? Could the amplifier be putting out more than it should at 10 oclock ?

Please excuse my make shift work bench for now But these are 3 of the sets i have tried. Cornwalls, KG4sand the Pioneer Cs99as
 

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Ok tried with the Pioneers, they dont seem to pop at all . They will get to there limit and start distorting . There limit as i would call it is around 10 oclock on the volume and only pegging just above the 1 watt mark on the VU meter . It was loud and sounded good up until they started distorting. So i didnt want to push them any further but no pops?

It doesnt make since to me .? Could the amplifier be putting out more than it should at 10 oclock ?

Please excuse my make shift work bench for now But these are 3 of the sets i have tried. Cornwalls, KG4sand the Pioneer Cs99as

It still seems odd that you can't get the volume above 10'oclock. Try running one of the klipsh sets with the treble at minimum, if the amp has a high cut filter engage that as well.
 
Sansui 7070

Just a thought , could it be the caps on one of the boards that the bass, mid, treble are connected to ?

Perhaps, but I'd like to see if this is more of a high freq issue first. If its all in the highs maybe there is some arcing in the power supply, more specifically, I would look at the power switch. Unplug the receiver and try to solder a jumper wire across the normally open contacts.

Joe
 
I believe you cleaned the switches and controls, however, I would work all those controls while listening at a low volume and see if any switches or controls make any excessive noise when their moved.
 
Perhaps, but I'd like to see if this is more of a high freq issue first. If its all in the highs maybe there is some arcing in the power supply, more specifically, I would look at the power switch. Unplug the receiver and try to solder a jumper wire across the normally open contacts.

Joe

Just tested with the Klipsch KG4s , the pop is present with or with out the high filter and tones set flat.
When you said arcing , that is what it sounds like to me out of the highs.

Not 100% on which contacts you are refering to ? I see 2 white wires going to the switch and a few pins sticking out of the switch housing ?
 
I believe you cleaned the switches and controls, however, I would work all those controls while listening at a low volume and see if any switches or controls make any excessive noise when their moved.

Done that , and yes i cleaned the controls good with the Deoxit D5 and Lube .
 
Ok tried with the Pioneers, they dont seem to pop at all . They will get to there limit and start distorting . There limit as i would call it is around 10 oclock on the volume and only pegging just above the 1 watt mark on the VU meter . It was loud and sounded good up until they started distorting. So i didnt want to push them any further but no pops?

It doesnt make since to me .? Could the amplifier be putting out more than it should at 10 oclock ?

Please excuse my make shift work bench for now But these are 3 of the sets i have tried. Cornwalls, KG4sand the Pioneer Cs99as

To answer you question, I never ran into an amp that put out excessive volume at a low volume setting. Also, the power meters register about 1 watt. It seems that you would have to have two separate issues for that to occur.
 
Just tested with the Klipsch KG4s , the pop is present with or with out the high filter and tones set flat.
When you said arcing , that is what it sounds like to me out of the highs.

Not 100% on which contacts you are refering to ? I see 2 white wires going to the switch and a few pins sticking out of the switch housing ?

If there are only two wires going to the switch then jumping the connection across those two would do it.
 
Well im open for suggestions or ideas ? I dont want to give this back to my friend if its only going to be a problem . Listening to it right now and just double checked . The pops are happening at or just before the .5 mark on the meter. It does seem to only come from the highs..

This has been running for a few hours now and sounds good other than the pops.
 
Basically bypassing the switch ?

Yes, but before you do that I would also check and clean the 120/240V selector plug on the back of the receiver (if it has it) and the main power fuse (F701) and fuse holder. Check the rest of the fuses for cleanliness and the fuse holders on the main board for good spring tension, pinch them inward a bit with your fingers if they seem loose.
 
Also look for poor solder connections at any of those points where wires attach to the power switch, fuse holders, plugs, etc. Inspect fuses and plug pins for any sign of arcing. Try spraying some cleaner into sockets and recessed fuse holders provided the cleaner you have is safe for plastics, otherwise use alcohol and Q-tips.
 
Joe i will do all the checks you asked , it will be tomrrow hopefully. About to call it a day on it for now .

thanks for all your time and help

Chris
 
Unplug the receiver and disconnect any speaker wires.

If you have a lighter gauge speaker wire (preferably 18 gauge), it will help to make connections easier as we will be soldering them directly to the motherboard.

Remove the black wire and jumper that is soldered across two of the RL01 relay pins (foil side), tape off the bare wire and push it aside.

See the attached diagram.

Look for the two yellow dots in the diagram; this is where you will solder the positive sides of the left and right speaker wires. Solder the left positive speaker wire to the relay side of L01, and the right positive speaker wire to the relay side of L02. Connect the two negative speaker wires to the negative “A” speaker output terminals on the receiver.

Hook up a set of speakers to the other end of the speaker wires, however, LEAVE THE NEGATIVE SPEAKER WIRES DISCONNECTED FOR NOW AND PUT SOME ELECTRICAL TAPE OR WIRE NUTS OVER THE ENDS OF THOSE WIRES.

Remove R29 (4.7 Ohm fusible) on the motherboard

Set the volume and bass to minimum, loudness switch off, and power up the receiver. Wait 10 seconds, (time for the amp to stabilize) then connect the negative speaker wires to the speakers, it doesn’t matter which one goes to which as they both connect at the same point inside the receiver.

Keep one finger on the power switch in case something goes wrong during the test. (there shouldn’t be any problem at minimum volume, it gets more important as you try to push the volume up.)

Slowly turn up the volume and see if you can get past the 9 o’clock position without distortion, see if you can get it to 11 o’clock but don’t go past that for now.

If it holds, decrease the volume to the 8 o’clock position and turn the bass control to mid position, try to increase the volume back to 11 o’clock - but no further, as it would probably pop the inline fuses.

After the test, drop the volume down to minimum. One at a time, disconnect a negative speaker wire from one of the speakers and cap it or tape it off, do the same for the other speaker.

Power down, unplug the receiver and let me know the result.

Should i go ahead and put this back as it was originaly ? I take it we are dont with this test ?
 
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