Question about NAD C272 Amplifier

2 Answers

NAD C272 Amplifier: Intermittent left channel

My NAD C272 has developed an intermittent fault where the left channel goes completely dead until I give it a good wallop, at which point it returns. It seems to get more reliable when the amplifier has warmed up. So I assumed it was a dry joint or intermittent connection, but when I took the back off I was unable to replicate the fault. Its not the pre-amp or source components, because the problem stays on the left speaker when I swap the amplifier inputs over. I've replaced the cables with no effect. Has anyone seen similar problems? Do you know where I can get hold of a technical manual?

Thanks in advance.


Posted by on

  • 1 more comment 
  • edreg May 07, 2008

    I have a NAD C270 amp with the same intermittent problem did the solution suggested work ?

  • Iordan Nov 25, 2008

    I have a similar problem. My amplifier is a Teac A-X800 DC. The problem definitely only occurs at low volume. When I increase the volume the problem disappears. How can I identify the output protection relay?


  • Pieter Vleeshouwers
    Pieter Vleeshouwers Nov 23, 2016

    Buy a canister contact spray for your potentiometers and switches first but don,t forget also a canister of coldspray to spray on parts what react on thermical failures like these , in most cases dirth on electroprints should be the first thought second some bad dried elco capacitors replace all neccesary to get harmony again on your power supply so 1 component leaking or lost capacitance replace all capacitors thats fitted on the end-stage.



2 Answers

  • Level 1:

    An expert who has achieved level 1.


    An expert that has over 10 points.


    An expert whose answer got voted for 2 times.

    Problem Solver:

    An expert who has answered 5 questions.

  • Contributor
  • 4 Answers

My solution was actually indeed the output protection relay. What I did was to open up the relay and use contact cleaner and a very fine abrasive to clean the contact surfaces of the relay. After that, the problem was gone!

The way to diagnose this for me was to run the amplifier open until the problem recurred and to simply tap the relay's box. The sound came on immediately, and I was convinced.

Posted on Feb 05, 2009

  • Jesus Rincom Apr 15, 2012

    Hi, how did you open the relays, Would you give me some tips. Thank

  • Iordan Apr 17, 2012

    Hey Jesus,

    Well, when I looked at my relay, and moved the top (the cap), it was obvious that the top comes off. I can't remember whether it was glued to the bottom or not, but if you see a seam at the bottom and try to work a utility knife along the seam perhaps you would be able to pry it open. I think there are also sealed ones that won't open up! If that's the case, then can't you order a replacement relay? Surely it would cost little compared to throwing away the entire amplifier.



  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 20 achievements.


    An expert that got 10 achievements.


    An expert that got 5 achievements.

  • Master
  • 4,234 Answers

Based upon your description of the problem, there are a few possiblities. First a question: does this problem occur more often with low volume? If so, I'd suspect a bad output protection relay. If it is independent of the volume, resolder all of the connections in the output section. It may not look like a bad connection, but it is there.

Keep us updated.

Posted on Apr 03, 2008


1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya Technician can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repair professionals here in the US.
click here to Talk to a Technician (only for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

NAD c272 distrotion may have to replace the stk output amp ic or the discrete transistors for the channel affected.....good success, regards, Meder's tv service

Aug 15, 2012 | NAD C272 Amplifier

2 Answers

Nad c370 keeps switching off

Check the speaker wiring for shorts, a common problem. If everything checks out there may be bad solder joints on the main board especially in the output stage, or there is a fault in one or more driver transistors.

Jun 02, 2012 | NAD C370 2-Channel Amplifier

3 Answers

NAD C272 AMP has little volume and sound is muddy and distorted.

Normaly this is what cause little volum and distortion. Check first if you got +68/-68V on amp module left and right Often the -68V is missing. This is caused by faulty transistor Q712 (2SA872) in +68/-68V power supply.

Feb 27, 2010 | NAD C272 Amplifier

1 Answer

My Rotel RA-931 integrated has an intermittent left channel. It occasionally cuts out or loses most of its volume. The key thing is this: if I crank the volume it'll suddenly come back and be okay for a...

This could be a bad solder joint, or dirt in the volume control. Try spraying the volume control with Servisol Video 40, available from electronic shops such as Maplin, or Radio Shack.

Dec 22, 2009 | NAD C272 Amplifier

1 Answer

Nad c 370 no power

You need to look inside. There will be a fuse inside too. If your lucky it will restore the amp once replaced, but if it blows again you have a fault. You can track it down yourself if your any good, you might even see a burnt out part when looking for that fuse, otherwise get the repairman in.

Sep 20, 2009 | NAD C370 2-Channel Amplifier

1 Answer

Losing the right channel

usually this would indicate a dry joint inside or some other temp related intermittent fault, component problem. Take it to a tech and tell them what happens

Sep 17, 2009 | NAD C370 2-Channel Amplifier

1 Answer

Is there a reset button for the NAD Surround Sound Receiver T 751

The only reset that i know of is to unplug it for 15 to 20 minutes. Hope this helps.

Dec 03, 2008 | NAD T751 Receiver

1 Answer


Hi Jimbob. Sounds like you have dirty/dry controls/switches. The contact lubricant dries out on them producing intermittent and scratchiness when you operate them. Clean any offending controls or signal switches with CRC2-26 by squirting(to flood then internals) each control/switch. you will have to do this from the inside of the amp. You may also have a dirty speaker protection relay, sound may return to a dead channel when you turn the vol up points to that. Good Luck. If you need more info feel free to get back to me here. Happy to talk you through more if you cant sort it out.


Mar 22, 2008 | Sony TA-FE370 2-Channel Amplifier

2 Answers

Nad s200

It is most probably a dirty speaker protection relay. gently tap the relay(the one that engages shortly after turning the amp on) when the fault is occurring and see audio returns. This should ascertain the problem. Replace it if it is a sealed type, or if it has a "lid" you can get off, burnish the contacts with a white business card, and give it a spray with contact cleaner/lubricant. Good luck and a "fixYa" rating would be great for my profile :)

Feb 06, 2008 | NAD C370 2-Channel Amplifier

1 Answer

Output volume has dropped in right channel

dear sir,pls check the HT voltage fuse, LTsupplay also and out put stage,and volume controle,

Jan 17, 2007 | NAD C350 2-Channel Amplifier

Not finding what you are looking for?
NAD C272 Amplifier Logo

Related Topics:

1,475 people viewed this question

Ask a Question

Usually answered in minutes!

Top NAD Audio Players & Recorders Experts


Level 3 Expert

5259 Answers

The Knight
The Knight

Level 3 Expert

74666 Answers

Donald DCruz
Donald DCruz

Level 3 Expert

17130 Answers

Are you a NAD Audio Player and Recorder Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides