NAD 3130 - Page 1
Forum section: electronics / repair

author: MikeW
author_rank: Regular Contributor
timestamp: July 24, 2015, 06:15:18 pm
content: I have a NAD 3130 amplifier and it's a little unhealthy.Basically sometimes the channels will flicker in and out, especially at lower volumes. Both can do it, seems to be no preference.Is it worth getting it open to have a look for obvious fixable causes or is it a sign of terminal illness?I'm quite loathe to get rid of it as it's about30 years old and has always been in the family. Throwing it out would actually be a bit emotional.I'm a bit scared of poking around inside amps as they can have some pretty big caps inside can't they?

author: kripton2035
author_rank: Super Contributor
timestamp: July 24, 2015, 07:20:19 pm
content: you must clean the volume potentiometer, or change it if you find the same.

author: picandmix
author_rank: Frequent Contributor
timestamp: July 24, 2015, 07:54:23 pm
content: Well worth opening it up to check for anything obvious.My amp suffered from the pcb mounted fuse holders, spring clip type, becoming weak and loosing good contact; both the one for the mains supply and the ones for each of the power amp sections.Equally check for poor cable / connectors and dry joints etc.The large caps should drain fairly quick after the amp is powered off, assuming you keep the speakers connected, but still be careful.

author: divelectservices
author_rank: Contributor
timestamp: July 24, 2015, 08:00:58 pm
content: I work on a lot of NAD products...which is not a good statement of their quality in the last 15 years.Currently working on a T 752 from hell!I can maybe give you some places to start looking if you can be more specific about the symptoms.What do mean by "flicker"? Are the channels cutting out completely, but the amp stay on, or does the amp power off also when it happens?

author: Seekonk
author_rank: Super Contributor
timestamp: July 24, 2015, 08:13:12 pm
content: Worked on a NAD that had a flaky thermal breaker in series with the speaker output.

author: MikeW
author_rank: Regular Contributor
timestamp: July 24, 2015, 08:32:19 pm
content: Quote from: divelectservices on July 24, 2015, 08:00:58 pmSo one channel, I think it's mainly the left will just randomly cut out for a bit then come back in. Could be for a few seconds, could be a minute or two, then it might do it again a couple seconds later or a couple hours later. It's sat on a solid surface and I'm not driving it hard at all, not playing any bassy music or anything to be vibrating any connections hard, just watching tv through it. (although I will confess I did kinda used to punish it in my dnb days)A lot of the time turning it up will help it come back but not always.It doesn't power off at all.It can have a little distortion to it when it flickers too

author: Smith
author_rank: Frequent Contributor
timestamp: July 25, 2015, 07:32:10 am
content: Amps with distortion or disapearing audio on single or multiple channels on low levels (comming back on higher levels or more bass) usually mean the speaker output relays. This can easely be checked by cleaning the contacts with some paper and IPA, or bypassing them with a wire.If it only gets worse or better when turning the pots or input switches, you guessed it, it's probably the responding pot or input switch.If both are not the case, look for bad solder joint, starting at the output transistors.

author: dom0
author_rank: Super Contributor
timestamp: July 25, 2015, 09:43:57 am
content: Quote from: Smith on July 25, 2015, 07:32:10 amAlso speaker group switches, if the amp has them.