so heres the issue.
when playing from any input, hardly any noise from right channel, realy loud on left channel, but realy loud on left channel even with the volume control turned down to 0
😕
when playing from any input, hardly any noise from right channel, realy loud on left channel, but realy loud on left channel even with the volume control turned down to 0
😕
If the noise is on all sources, you would expect it not to be affected by the volume control.
The volume control is before the amplifier circuitry. It could be a lot of things, not easy to fix.
Unless you have worked on similar circuitry before, take it to a technician.
The volume control is before the amplifier circuitry. It could be a lot of things, not easy to fix.
Unless you have worked on similar circuitry before, take it to a technician.
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so i tried this amp out before i sold it to my friend,i even videoed it as i tested it and before that i had re capped it, but it was fine before i sent it to him through the post
All sorts of things can cause noises. Bad resistor, capacitor, transistor, solder joint, connection, switch.
Sometimes the problem comes and goes with temperature or vibration. It can take a lot of work
to find it. In old gear, problems can happen at any time, for no reason.
Sometimes the problem comes and goes with temperature or vibration. It can take a lot of work
to find it. In old gear, problems can happen at any time, for no reason.
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i guess i just have to work my way through it then untill i find out whats wrong because when i sent it, the unit was perfect, when it got to the other end it wasnt.
i have had the top and bottom covers off and nothing obvious, no burning,loose joints ,caps round the wrong way(these were all brand new nichicon caps) no fuses blown.all the switches were cleaned with compressed air then servisol- it just doesnt make sense.
i have had the top and bottom covers off and nothing obvious, no burning,loose joints ,caps round the wrong way(these were all brand new nichicon caps) no fuses blown.all the switches were cleaned with compressed air then servisol- it just doesnt make sense.
Old equipment can fail in many ways, at any time. Read about the bathtub curve.
Bathtub curve - Wikipedia
Bathtub curve - Wikipedia
yep i get that one as i work in engineering, so i do get that one.All i can put it down to is something happened in transit, so now i have to find out what, i just though one of you guys may have been able to give me a pointer.I have several amps with seperate pre/power so i can at least start by eliminating if it is one or the other of those first and take it from there,thanks anyway.
Could you be a bit more specific.
When you say playing from any input. Do you mean you had music playing?
Sid
When you say playing from any input. Do you mean you had music playing?
Sid
As I understand, parcels handling in the UK can be more than a bit rough - systemically. NAD's chassis also aren't the most robust and its likely the PCB or at least connections between items like pots, switches and jacks that bridge the chassis and PCB have been stressed, solder joints or copper traces broken etc.
Checking this out may not be just a matter of visual inspection. You'll need to look at suspect signal controls and apply a little force that might remake a broken circuit or possibly open a short but use your engineering judgement regarding how brittle the paper/phenolic boards are and how much force is allowable to pull or prise those cable connectors apart without breaking the board or solder joints. Too much pressure and bang! .....there goes your pride and your cash.
Checking this out may not be just a matter of visual inspection. You'll need to look at suspect signal controls and apply a little force that might remake a broken circuit or possibly open a short but use your engineering judgement regarding how brittle the paper/phenolic boards are and how much force is allowable to pull or prise those cable connectors apart without breaking the board or solder joints. Too much pressure and bang! .....there goes your pride and your cash.
yes i even have a video of it just before i buttoned it up and packed it for sending out, its very weird
i played music through each input, and they all sounded normal.
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Next time use too much cushioning in a sturdy box.
It got thrown about or crushed in transit..
So it seems flimsy.
Now if you do get it back, same way, maybe it will fix itself.
Ask the receiver to swap inputs, maybe his source has a problem.
Wrap in paper, then tape plywood or any similar material to the unit, then pack in a carton with no gap between carton and unit, having put sheets of Styrofoam or similar cushion material.
Use a strong 5 or 7 ply carton.
And then hope for the best.
It got thrown about or crushed in transit..
So it seems flimsy.
Now if you do get it back, same way, maybe it will fix itself.
Ask the receiver to swap inputs, maybe his source has a problem.
Wrap in paper, then tape plywood or any similar material to the unit, then pack in a carton with no gap between carton and unit, having put sheets of Styrofoam or similar cushion material.
Use a strong 5 or 7 ply carton.
And then hope for the best.
so to start with i have swapped over the phono board and volume pcb.for some reason now it is blowing one of the 1a fused so i checked the other rectifier and that appeared to be faulty so i swapped that over with a good one.now when i turn it one one of the 1w resistors starts to glow (r506) so i am a bit stuck again now.The power on LED does not come on either now.Its all getting a bit of a mystery.
so this turned out to be my own fault, user error im affraid,an one i should not have made having done fault finding for years on M and E equipment.When swapping the phono and volume boards over with good known units i got a pair of wires mixed up and connected incorrectly.I only noticed it because i had taken photos of all the cables and connections before hand and noticed it as i was checking back through.so i guess you live and learn(sometimes the hard way)